1 <html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>The Altus Metrum System</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="book"><div class="titlepage"><div><div><h1 class="title"><a name="idp26428432"></a>The Altus Metrum System</h1></div><div><h2 class="subtitle">An Owner's Manual for Altus Metrum Rocketry Electronics</h2></div><div><div class="author"><h3 class="author"><span class="firstname">Bdale</span> <span class="surname">Garbee</span></h3></div></div><div><div class="author"><h3 class="author"><span class="firstname">Keith</span> <span class="surname">Packard</span></h3></div></div><div><div class="author"><h3 class="author"><span class="firstname">Bob</span> <span class="surname">Finch</span></h3></div></div><div><div class="author"><h3 class="author"><span class="firstname">Anthony</span> <span class="surname">Towns</span></h3></div></div><div><p class="copyright">Copyright © 2013 Bdale Garbee and Keith Packard</p></div><div><div class="legalnotice"><a name="idp53658176"></a><p>
2 This document is released under the terms of the
3 <a class="ulink" href="http://creativecommons.org/licenses/by-sa/3.0/" target="_top">
4 Creative Commons ShareAlike 3.0
7 </p></div></div><div><div class="revhistory"><table style="border-style:solid; width:100%;" summary="Revision History"><tr><th align="left" valign="top" colspan="2"><b>Revision History</b></th></tr><tr><td align="left">Revision 1.3</td><td align="left">12 November 2013</td></tr><tr><td align="left" colspan="2">
8 Updated for software version 1.3. Version 1.3 adds support
9 for TeleMega, TeleMetrum v2.0, TeleMini v2.0 and EasyMini
10 and fixes bugs in AltosUI and the AltOS firmware.
11 </td></tr><tr><td align="left">Revision 1.2.1</td><td align="left">21 May 2013</td></tr><tr><td align="left" colspan="2">
12 Updated for software version 1.2. Version 1.2 adds support
13 for TeleBT and AltosDroid. It also adds a few minor features
14 and fixes bugs in AltosUI and the AltOS firmware.
15 </td></tr><tr><td align="left">Revision 1.2</td><td align="left">18 April 2013</td></tr><tr><td align="left" colspan="2">
16 Updated for software version 1.2. Version 1.2 adds support
17 for MicroPeak and the MicroPeak USB interface.
18 </td></tr><tr><td align="left">Revision 1.1.1</td><td align="left">16 September 2012</td></tr><tr><td align="left" colspan="2">
19 Updated for software version 1.1.1 Version 1.1.1 fixes a few
20 bugs found in version 1.1.
21 </td></tr><tr><td align="left">Revision 1.1</td><td align="left">13 September 2012</td></tr><tr><td align="left" colspan="2">
22 Updated for software version 1.1. Version 1.1 has new
23 features but is otherwise compatible with version 1.0.
24 </td></tr><tr><td align="left">Revision 1.0</td><td align="left">24 August 2011</td></tr><tr><td align="left" colspan="2">
25 Updated for software version 1.0. Note that 1.0 represents a
26 telemetry format change, meaning both ends of a link
27 (TeleMetrum/TeleMini and TeleDongle) must be updated or
28 communications will fail.
29 </td></tr><tr><td align="left">Revision 0.9</td><td align="left">18 January 2011</td></tr><tr><td align="left" colspan="2">
30 Updated for software version 0.9. Note that 0.9 represents a
31 telemetry format change, meaning both ends of a link (TeleMetrum and
32 TeleDongle) must be updated or communications will fail.
33 </td></tr><tr><td align="left">Revision 0.8</td><td align="left">24 November 2010</td></tr><tr><td align="left" colspan="2">Updated for software version 0.8 </td></tr></table></div></div></div><hr></div><div class="dedication"><div class="titlepage"><div><div><h1 class="title"><a name="idp52772352"></a>Acknowledgments</h1></div></div></div><p>
34 Thanks to Bob Finch, W9YA, NAR 12965, TRA 12350 for writing “The
35 Mere-Mortals Quick Start/Usage Guide to the Altus Metrum Starter
36 Kit” which formed the basis of the original Getting Started chapter
37 in this manual. Bob was one of our first customers for a production
38 TeleMetrum, and his continued enthusiasm and contributions
39 are immensely gratifying and highly appreciated!
41 And thanks to Anthony (AJ) Towns for major contributions including
42 the AltosUI graphing and site map code and associated documentation.
43 Free software means that our customers and friends can become our
44 collaborators, and we certainly appreciate this level of
47 Have fun using these products, and we hope to meet all of you
48 out on the rocket flight line somewhere.
49 </p><div class="literallayout"><p><br>
50 Bdale Garbee, KB0G<br>
51 NAR #87103, TRA #12201<br>
53 Keith Packard, KD7SQG<br>
54 NAR #88757, TRA #12200<br>
56 </p></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="chapter"><a href="#idp52776880">1. Introduction and Overview</a></span></dt><dt><span class="chapter"><a href="#idp57459264">2. Getting Started</a></span></dt><dt><span class="chapter"><a href="#idp52778544">3. Handling Precautions</a></span></dt><dt><span class="chapter"><a href="#idp52784032">4. Altus Metrum Hardware</a></span></dt><dd><dl><dt><span class="section"><a href="#idp52784704">1. Overview</a></span></dt><dt><span class="section"><a href="#idp58332736">2. TeleMetrum</a></span></dt><dt><span class="section"><a href="#idp58337760">3. TeleMini</a></span></dt><dt><span class="section"><a href="#idp58346160">4. EasyMini</a></span></dt><dt><span class="section"><a href="#idp58350144">5. TeleMega</a></span></dt><dt><span class="section"><a href="#idp58354240">6. Flight Data Recording</a></span></dt><dt><span class="section"><a href="#idp58383072">7. Installation</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp58389808">5. System Operation</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58390448">1. Firmware Modes </a></span></dt><dt><span class="section"><a href="#idp58467152">2. GPS </a></span></dt><dt><span class="section"><a href="#idp58469936">3. Controlling An Altimeter Over The Radio Link</a></span></dt><dt><span class="section"><a href="#idp58481232">4. Ground Testing </a></span></dt><dt><span class="section"><a href="#idp58483984">5. Radio Link </a></span></dt><dt><span class="section"><a href="#idp58488672">6. Configurable Parameters</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58490416">6.1. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp58492464">6.2. Apogee Delay</a></span></dt><dt><span class="section"><a href="#idp58495056">6.3. Main Deployment Altitude</a></span></dt><dt><span class="section"><a href="#idp58496752">6.4. Maximum Flight Log</a></span></dt><dt><span class="section"><a href="#idp58498896">6.5. Ignite Mode</a></span></dt><dt><span class="section"><a href="#idp58501008">6.6. Pad Orientation</a></span></dt><dt><span class="section"><a href="#idp58502704">6.7. Configurable Pyro Channels</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="#idp58525184">6. AltosUI</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58528800">1. Monitor Flight</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58541520">1.1. Launch Pad</a></span></dt><dt><span class="section"><a href="#idp58557152">1.2. Ascent</a></span></dt><dt><span class="section"><a href="#idp58562608">1.3. Descent</a></span></dt><dt><span class="section"><a href="#idp58569472">1.4. Landed</a></span></dt><dt><span class="section"><a href="#idp58575904">1.5. Table</a></span></dt><dt><span class="section"><a href="#idp58579488">1.6. Site Map</a></span></dt></dl></dd><dt><span class="section"><a href="#idp58585152">2. Save Flight Data</a></span></dt><dt><span class="section"><a href="#idp58589632">3. Replay Flight</a></span></dt><dt><span class="section"><a href="#idp58591664">4. Graph Data</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58594048">4.1. Flight Graph</a></span></dt><dt><span class="section"><a href="#idp58598496">4.2. Configure Graph</a></span></dt><dt><span class="section"><a href="#idp58602160">4.3. Flight Statistics</a></span></dt><dt><span class="section"><a href="#idp58605680">4.4. Map</a></span></dt></dl></dd><dt><span class="section"><a href="#idp58609536">5. Export Data</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58611648">5.1. Comma Separated Value Format</a></span></dt><dt><span class="section"><a href="#idp58614000">5.2. Keyhole Markup Language (for Google Earth)</a></span></dt></dl></dd><dt><span class="section"><a href="#idp58615488">6. Configure Altimeter</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58627792">6.1. Main Deploy Altitude</a></span></dt><dt><span class="section"><a href="#idp58629360">6.2. Apogee Delay</a></span></dt><dt><span class="section"><a href="#idp58630976">6.3. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp58632480">6.4. RF Calibration</a></span></dt><dt><span class="section"><a href="#idp58634128">6.5. Telemetry/RDF/APRS Enable</a></span></dt><dt><span class="section"><a href="#idp58635424">6.6. APRS Interval</a></span></dt><dt><span class="section"><a href="#idp58636928">6.7. Callsign</a></span></dt><dt><span class="section"><a href="#idp58638240">6.8. Maximum Flight Log Size</a></span></dt><dt><span class="section"><a href="#idp58639680">6.9. Ignite Mode</a></span></dt><dt><span class="section"><a href="#idp58646672">6.10. Pad Orientation</a></span></dt><dt><span class="section"><a href="#idp58651888">6.11. Configure Pyro Channels</a></span></dt></dl></dd><dt><span class="section"><a href="#idp58657696">7. Configure AltosUI</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58661200">7.1. Voice Settings</a></span></dt><dt><span class="section"><a href="#idp58666224">7.2. Log Directory</a></span></dt><dt><span class="section"><a href="#idp58668224">7.3. Callsign</a></span></dt><dt><span class="section"><a href="#idp58670464">7.4. Imperial Units</a></span></dt><dt><span class="section"><a href="#idp58671968">7.5. Font Size</a></span></dt><dt><span class="section"><a href="#idp58673248">7.6. Serial Debug</a></span></dt><dt><span class="section"><a href="#idp58674752">7.7. Manage Frequencies</a></span></dt></dl></dd><dt><span class="section"><a href="#idp58676384">8. Configure Groundstation</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58687504">8.1. Frequency</a></span></dt><dt><span class="section"><a href="#idp58689072">8.2. Radio Calibration</a></span></dt></dl></dd><dt><span class="section"><a href="#idp58690704">9. Flash Image</a></span></dt><dt><span class="section"><a href="#idp58692336">10. Fire Igniter</a></span></dt><dt><span class="section"><a href="#idp58697968">11. Scan Channels</a></span></dt><dt><span class="section"><a href="#idp58701824">12. Load Maps</a></span></dt><dt><span class="section"><a href="#idp58707520">13. Monitor Idle</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp58709616">7. AltosDroid</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58712000">1. Installing AltosDroid</a></span></dt><dt><span class="section"><a href="#idp58713936">2. Connecting to TeleBT</a></span></dt><dt><span class="section"><a href="#idp58715936">3. Configuring AltosDroid</a></span></dt><dt><span class="section"><a href="#idp58717392">4. AltosDroid Flight Monitoring</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58718704">4.1. Pad</a></span></dt></dl></dd><dt><span class="section"><a href="#idp58732256">5. Downloading Flight Logs</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp58733920">8. Using Altus Metrum Products</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58734560">1. Being Legal</a></span></dt><dt><span class="section"><a href="#idp58736464">2. In the Rocket</a></span></dt><dt><span class="section"><a href="#idp58738928">3. On the Ground</a></span></dt><dt><span class="section"><a href="#idp58752240">4. Data Analysis</a></span></dt><dt><span class="section"><a href="#idp58754784">5. Future Plans</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp58759168">9. Altimeter Installation Recommendations</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58760624">1. Mounting the Altimeter</a></span></dt><dt><span class="section"><a href="#idp58766032">2. Dealing with the Antenna</a></span></dt><dt><span class="section"><a href="#idp58771600">3. Preserving GPS Reception</a></span></dt><dt><span class="section"><a href="#idp58776384">4. Radio Frequency Interference</a></span></dt><dt><span class="section"><a href="#idp58783952">5. The Barometric Sensor</a></span></dt><dt><span class="section"><a href="#idp58786752">6. Ground Testing</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp58789920">10. Updating Device Firmware</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58793936">1.
57 Updating TeleMega, TeleMetrum v2 or EasyMini Firmware
58 </a></span></dt><dd><dl><dt><span class="section"><a href="#idp58802752">1.1. Recovering From Self-Flashing Failure</a></span></dt></dl></dd><dt><span class="section"><a href="#idp58811728">2. Pair Programming</a></span></dt><dt><span class="section"><a href="#idp58813168">3. Updating TeleMetrum v1.x Firmware</a></span></dt><dt><span class="section"><a href="#idp58826208">4. Updating TeleMini Firmware</a></span></dt><dt><span class="section"><a href="#idp58839600">5. Updating TeleDongle Firmware</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp58856144">11. Hardware Specifications</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58856784">1.
59 TeleMega Specifications
60 </a></span></dt><dt><span class="section"><a href="#idp58868016">2.
61 TeleMetrum v2 Specifications
62 </a></span></dt><dt><span class="section"><a href="#idp58878256">3. TeleMetrum v1 Specifications</a></span></dt><dt><span class="section"><a href="#idp58888496">4.
63 TeleMini v2.0 Specifications
64 </a></span></dt><dt><span class="section"><a href="#idp58897328">5.
65 TeleMini v1.0 Specifications
66 </a></span></dt><dt><span class="section"><a href="#idp58906128">6.
67 EasyMini Specifications
68 </a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp58914240">12. FAQ</a></span></dt><dt><span class="appendix"><a href="#idp58923088">A. Notes for Older Software</a></span></dt><dt><span class="appendix"><a href="#idp58946464">B. Drill Templates</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58947632">1. TeleMega template</a></span></dt><dt><span class="section"><a href="#idp58963600">2. TeleMetrum template</a></span></dt><dt><span class="section"><a href="#idp58967264">3. TeleMini v2/EasyMini template</a></span></dt><dt><span class="section"><a href="#idp58970944">4. TeleMini v1 template</a></span></dt></dl></dd><dt><span class="appendix"><a href="#idp58974736">C. Calibration</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58976288">1. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp58980832">2. TeleMetrum and TeleMega Accelerometers</a></span></dt></dl></dd><dt><span class="appendix"><a href="#idp58985936">D. Release Notes</a></span></dt></dl></div><div class="list-of-tables"><p><b>List of Tables</b></p><dl><dt>4.1. <a href="#idp52785760">Altus Metrum Electronics</a></dt><dt>4.2. <a href="#idp56763616">Altus Metrum Boards</a></dt><dt>4.3. <a href="#idp58355648">Data Storage on Altus Metrum altimeters</a></dt><dt>5.1. <a href="#idp58391728">AltOS Modes</a></dt><dt>5.2. <a href="#idp58440960">Pad/Idle Indications</a></dt></dl></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp52776880"></a>Chapter 1. Introduction and Overview</h1></div></div></div><p>
69 Welcome to the Altus Metrum community! Our circuits and software reflect
70 our passion for both hobby rocketry and Free Software. We hope their
71 capabilities and performance will delight you in every way, but by
72 releasing all of our hardware and software designs under open licenses,
73 we also hope to empower you to take as active a role in our collective
76 The first device created for our community was TeleMetrum, a dual
77 deploy altimeter with fully integrated GPS and radio telemetry
78 as standard features, and a “companion interface” that will
79 support optional capabilities in the future. The latest version
80 of TeleMetrum, v2.0, has all of the same features but with
81 improved sensors and radio to offer increased performance.
83 Our second device was TeleMini, a dual deploy altimeter with
84 radio telemetry and radio direction finding. The first version
85 of this device was only 13mm by 38mm (½ inch by 1½ inches) and
86 could fit easily in an 18mm air-frame. The latest version, v2.0,
87 includes a beeper, USB data download and extended on-board
88 flight logging, along with an improved barometric sensor.
90 TeleMega is our most sophisticated device, including six pyro
91 channels (four of which are fully programmable), integrated GPS,
92 integrated gyroscopes for staging/air-start inhibit and high
93 performance telemetry.
95 EasyMini is a dual-deploy altimeter with logging and built-in
98 TeleDongle was our first ground station, providing a USB to RF
99 interfaces for communicating with the altimeters. Combined with
100 your choice of antenna and notebook computer, TeleDongle and our
101 associated user interface software form a complete ground
102 station capable of logging and displaying in-flight telemetry,
103 aiding rocket recovery, then processing and archiving flight
104 data for analysis and review.
106 For a slightly more portable ground station experience that also
107 provides direct rocket recovery support, TeleBT offers flight
108 monitoring and data logging using a Bluetooth™ connection between
109 the receiver and an Android device that has the AltosDroid
110 application installed from the Google Play store.
112 More products will be added to the Altus Metrum family over time, and
113 we currently envision that this will be a single, comprehensive manual
114 for the entire product family.
115 </p></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp57459264"></a>Chapter 2. Getting Started</h1></div></div></div><p>
116 The first thing to do after you check the inventory of parts in your
117 “starter kit” is to charge the battery.
119 For TeleMetrum and TeleMega, the battery can be charged by plugging it into the
120 corresponding socket of the device and then using the USB
121 cable to plug the flight computer into your computer's USB socket. The
122 on-board circuitry will charge the battery whenever it is plugged
123 in, because the on-off switch does NOT control the
126 On TeleMetrum v1 boards, when the GPS chip is initially
127 searching for satellites, TeleMetrum will consume more current
128 than it pulls from the USB port, so the battery must be
129 attached in order to get satellite lock. Once GPS is locked,
130 the current consumption goes back down enough to enable charging
131 while running. So it's a good idea to fully charge the battery
132 as your first item of business so there is no issue getting and
133 maintaining satellite lock. The yellow charge indicator led
134 will go out when the battery is nearly full and the charger goes
135 to trickle charge. It can take several hours to fully recharge a
136 deeply discharged battery.
138 TeleMetrum v2.0 and TeleMega use a higher power battery charger,
139 allowing them to charge the battery while running the board at
140 maximum power. When the battery is charging, or when the board
141 is consuming a lot of power, the red LED will be lit. When the
142 battery is fully charged, the green LED will be lit. When the
143 battery is damaged or missing, both LEDs will be lit, which
146 The Lithium Polymer TeleMini and EasyMini battery can be charged by
147 disconnecting it from the board and plugging it into a
148 standalone battery charger such as the LipoCharger product
149 included in TeleMini Starter Kits, and connecting that via a USB
150 cable to a laptop or other USB power source.
152 You can also choose to use another battery with TeleMini v2.0
153 and EasyMini, anything supplying between 4 and 12 volts should
154 work fine (like a standard 9V battery), but if you are planning
155 to fire pyro charges, ground testing is required to verify that
156 the battery supplies enough current to fire your chosen e-matches.
158 The other active device in the starter kit is the TeleDongle USB to
159 RF interface. If you plug it in to your Mac or Linux computer it should
160 “just work”, showing up as a serial port device. Windows systems need
161 driver information that is part of the AltOS download to know that the
162 existing USB modem driver will work. We therefore recommend installing
163 our software before plugging in TeleDongle if you are using a Windows
164 computer. If you are using an older version of Linux and are having
165 problems, try moving to a fresher kernel (2.6.33 or newer).
167 Next you should obtain and install the AltOS software. The AltOS
168 distribution includes the AltosUI ground station program, current
170 images for all of the hardware, and a number of standalone
171 utilities that are rarely needed. Pre-built binary packages are
172 available for Linux, Microsoft Windows, and recent MacOSX
173 versions. Full source code and build instructions are also
174 available. The latest version may always be downloaded from
175 <a class="ulink" href="http://altusmetrum.org/AltOS" target="_top">http://altusmetrum.org/AltOS</a>.
177 If you're using a TeleBT instead of the TeleDongle, you'll want to
178 install the AltosDroid application from the Google Play store on an
179 Android device. You don't need a data plan to use AltosDroid, but
180 without network access, the Map view will be less useful as it
181 won't contain any map data. You can also use TeleBT connected
182 over USB with your laptop computer; it acts exactly like a
183 TeleDongle. Anywhere this manual talks about TeleDongle, you can
184 also read that as 'and TeleBT when connected via USB'.
185 </p></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp52778544"></a>Chapter 3. Handling Precautions</h1></div></div></div><p>
186 All Altus Metrum products are sophisticated electronic devices.
187 When handled gently and properly installed in an air-frame, they
188 will deliver impressive results. However, as with all electronic
189 devices, there are some precautions you must take.
191 The Lithium Polymer rechargeable batteries have an
192 extraordinary power density. This is great because we can fly with
193 much less battery mass than if we used alkaline batteries or previous
194 generation rechargeable batteries... but if they are punctured
195 or their leads are allowed to short, they can and will release their
197 Thus we recommend that you take some care when handling our batteries
198 and consider giving them some extra protection in your air-frame. We
199 often wrap them in suitable scraps of closed-cell packing foam before
200 strapping them down, for example.
202 The barometric sensors used on all of our flight computers are
203 sensitive to sunlight. In normal mounting situations, the baro sensor
204 and all of the other surface mount components
205 are “down” towards whatever the underlying mounting surface is, so
206 this is not normally a problem. Please consider this when designing an
207 installation in an air-frame with a see-through plastic payload bay. It
208 is particularly important to
209 consider this with TeleMini v1.0, both because the baro sensor is on the
210 “top” of the board, and because many model rockets with payload bays
211 use clear plastic for the payload bay! Replacing these with an opaque
212 cardboard tube, painting them, or wrapping them with a layer of masking
213 tape are all reasonable approaches to keep the sensor out of direct
216 The barometric sensor sampling port must be able to “breathe”,
217 both by not being covered by foam or tape or other materials that might
218 directly block the hole on the top of the sensor, and also by having a
219 suitable static vent to outside air.
221 As with all other rocketry electronics, Altus Metrum altimeters must
222 be protected from exposure to corrosive motor exhaust and ejection
224 </p></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp52784032"></a>Chapter 4. Altus Metrum Hardware</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp52784704">1. Overview</a></span></dt><dt><span class="section"><a href="#idp58332736">2. TeleMetrum</a></span></dt><dt><span class="section"><a href="#idp58337760">3. TeleMini</a></span></dt><dt><span class="section"><a href="#idp58346160">4. EasyMini</a></span></dt><dt><span class="section"><a href="#idp58350144">5. TeleMega</a></span></dt><dt><span class="section"><a href="#idp58354240">6. Flight Data Recording</a></span></dt><dt><span class="section"><a href="#idp58383072">7. Installation</a></span></dt></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp52784704"></a>1. Overview</h2></div></div></div><p>
225 Here's the full set of Altus Metrum products, both in
226 production and retired.
227 </p><div class="table"><a name="idp52785760"></a><p class="title"><b>Table 4.1. Altus Metrum Electronics</b></p><div class="table-contents"><table summary="Altus Metrum Electronics" border="1"><colgroup><col align="center" class="Device"><col align="center" class="Barometer"><col align="center" class="Z-axis accelerometer"><col align="center" class="GPS"><col align="center" class="3D sensors"><col align="center" class="Storage"><col align="center" class="RF"><col align="center" class="Battery"></colgroup><thead><tr><th align="center">Device</th><th align="center">Barometer</th><th align="center">Z-axis accelerometer</th><th align="center">GPS</th><th align="center">3D sensors</th><th align="center">Storage</th><th align="center">RF Output</th><th align="center">Battery</th></tr></thead><tbody><tr><td align="center">TeleMetrum v1.0</td><td align="center"><p>MP3H6115 10km (33k')</p></td><td align="center"><p>MMA2202 50g</p></td><td align="center">SkyTraq</td><td align="center">-</td><td align="center">1MB</td><td align="center">10mW</td><td align="center">3.7V</td></tr><tr><td align="center">TeleMetrum v1.1</td><td align="center"><p>MP3H6115 10km (33k')</p></td><td align="center"><p>MMA2202 50g</p></td><td align="center">SkyTraq</td><td align="center">-</td><td align="center">2MB</td><td align="center">10mW</td><td align="center">3.7V</td></tr><tr><td align="center">TeleMetrum v1.2</td><td align="center"><p>MP3H6115 10km (33k')</p></td><td align="center"><p>ADXL78 70g</p></td><td align="center">SkyTraq</td><td align="center">-</td><td align="center">2MB</td><td align="center">10mW</td><td align="center">3.7V</td></tr><tr><td align="center">TeleMetrum v2.0</td><td align="center"><p>MS5607 30km (100k')</p></td><td align="center"><p>MMA6555 102g</p></td><td align="center">uBlox Max-7Q</td><td align="center">-</td><td align="center">8MB</td><td align="center">40mW</td><td align="center">3.7V</td></tr><tr><td align="center"><p>TeleMini v1.0</p></td><td align="center"><p>MP3H6115 10km (33k')</p></td><td align="center">-</td><td align="center">-</td><td align="center">-</td><td align="center">5kB</td><td align="center">10mW</td><td align="center">3.7V</td></tr><tr><td align="center">TeleMini v2.0</td><td align="center"><p>MS5607 30km (100k')</p></td><td align="center">-</td><td align="center">-</td><td align="center">-</td><td align="center">1MB</td><td align="center">10mW</td><td align="center">3.7-12V</td></tr><tr><td align="center">EasyMini v1.0</td><td align="center"><p>MS5607 30km (100k')</p></td><td align="center">-</td><td align="center">-</td><td align="center">-</td><td align="center">1MB</td><td align="center">-</td><td align="center">3.7-12V</td></tr><tr><td align="center">TeleMega v1.0</td><td align="center"><p>MS5607 30km (100k')</p></td><td align="center"><p>MMA6555 102g</p></td><td align="center">uBlox Max-7Q</td><td align="center"><p>MPU6000 HMC5883</p></td><td align="center">8MB</td><td align="center">40mW</td><td align="center">3.7V</td></tr></tbody></table></div></div><br class="table-break"><div class="table"><a name="idp56763616"></a><p class="title"><b>Table 4.2. Altus Metrum Boards</b></p><div class="table-contents"><table summary="Altus Metrum Boards" border="1"><colgroup><col align="center" class="Device"><col align="center" class="Connectors"><col align="center" class="Screw Terminals"><col align="center" class="Width"><col align="center" class="Length"><col align="center" class="Tube Size"></colgroup><thead><tr><th align="center">Device</th><th align="center">Connectors</th><th align="center">Screw Terminals</th><th align="center">Width</th><th align="center">Length</th><th align="center">Tube Size</th></tr></thead><tbody><tr><td align="center">TeleMetrum</td><td align="center"><p>
233 </p></td><td align="center"><p>Apogee pyro Main pyro Switch</p></td><td align="center">1 inch (2.54cm)</td><td align="center">2 ¾ inch (6.99cm)</td><td align="center">29mm coupler</td></tr><tr><td align="center"><p>TeleMini v1.0</p></td><td align="center"><p>
237 </p></td><td align="center"><p>
240 </p></td><td align="center">½ inch (1.27cm)</td><td align="center">1½ inch (3.81cm)</td><td align="center">18mm coupler</td></tr><tr><td align="center">TeleMini v2.0</td><td align="center"><p>
245 </p></td><td align="center"><p>
250 </p></td><td align="center">0.8 inch (2.03cm)</td><td align="center">1½ inch (3.81cm)</td><td align="center">24mm coupler</td></tr><tr><td align="center">EasyMini</td><td align="center"><p>
254 </p></td><td align="center"><p>
259 </p></td><td align="center">0.8 inch (2.03cm)</td><td align="center">1½ inch (3.81cm)</td><td align="center">24mm coupler</td></tr><tr><td align="center">TeleMega</td><td align="center"><p>
265 </p></td><td align="center"><p>
271 </p></td><td align="center">1¼ inch (3.18cm)</td><td align="center">3¼ inch (8.26cm)</td><td align="center">38mm coupler</td></tr></tbody></table></div></div><br class="table-break"></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58332736"></a>2. TeleMetrum</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="telemetrum-v1.1-thside.jpg" width="495"></td></tr></table></div></div><p>
272 TeleMetrum is a 1 inch by 2¾ inch circuit board. It was designed to
273 fit inside coupler for 29mm air-frame tubing, but using it in a tube that
274 small in diameter may require some creativity in mounting and wiring
275 to succeed! The presence of an accelerometer means TeleMetrum should
276 be aligned along the flight axis of the airframe, and by default the ¼
277 wave UHF wire antenna should be on the nose-cone end of the board. The
278 antenna wire is about 7 inches long, and wiring for a power switch and
279 the e-matches for apogee and main ejection charges depart from the
280 fin can end of the board, meaning an ideal “simple” avionics
281 bay for TeleMetrum should have at least 10 inches of interior length.
282 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58337760"></a>3. TeleMini</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="telemini-v1-top.jpg" width="495"></td></tr></table></div></div><p>
283 TeleMini v1.0 is ½ inches by 1½ inches. It was
284 designed to fit inside an 18mm air-frame tube, but using it in
285 a tube that small in diameter may require some creativity in
286 mounting and wiring to succeed! Since there is no
287 accelerometer, TeleMini can be mounted in any convenient
288 orientation. The default ¼ wave UHF wire antenna attached to
289 the center of one end of the board is about 7 inches long. Two
290 wires for the power switch are connected to holes in the
291 middle of the board. Screw terminals for the e-matches for
292 apogee and main ejection charges depart from the other end of
293 the board, meaning an ideal “simple” avionics bay for TeleMini
294 should have at least 9 inches of interior length.
295 </p><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="telemini-v2-top.jpg" width="495"></td></tr></table></div></div><p>
296 TeleMini v2.0 is 0.8 inches by 1½ inches. It adds more
297 on-board data logging memory, a built-in USB connector and
298 screw terminals for the battery and power switch. The larger
299 board fits in a 24mm coupler. There's also a battery connector
300 for a LiPo battery if you want to use one of those.
301 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58346160"></a>4. EasyMini</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="easymini-top.jpg" width="495"></td></tr></table></div></div><p>
302 EasyMini is built on a 0.8 inch by 1½ inch circuit board. It's
303 designed to fit in a 24mm coupler tube. The connectors and
304 screw terminals match TeleMini v2.0, so you can easily swap between
305 EasyMini and TeleMini.
306 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58350144"></a>5. TeleMega</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="telemega-v1.0-top.jpg" width="495"></td></tr></table></div></div><p>
307 TeleMega is a 1¼ inch by 3¼ inch circuit board. It was
308 designed to easily fit in a 38mm coupler. Like TeleMetrum,
309 TeleMega has an accelerometer and so it must be mounted so that
310 the board is aligned with the flight axis. It can be mounted
311 either antenna up or down.
312 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58354240"></a>6. Flight Data Recording</h2></div></div></div><p>
313 Each flight computer logs data at 100 samples per second
314 during ascent and 10 samples per second during descent, except
315 for TeleMini v1.0, which records ascent at 10 samples per
316 second and descent at 1 sample per second. Data are logged to
317 an on-board flash memory part, which can be partitioned into
318 several equal-sized blocks, one for each flight.
319 </p><div class="table"><a name="idp58355648"></a><p class="title"><b>Table 4.3. Data Storage on Altus Metrum altimeters</b></p><div class="table-contents"><table summary="Data Storage on Altus Metrum altimeters" border="1"><colgroup><col align="center" class="Device"><col align="center" class="Bytes per sample"><col align="center" class="Total storage"><col align="center" class="Minutes of full-rate"></colgroup><thead><tr><th align="center">Device</th><th align="center">Bytes per Sample</th><th align="center">Total Storage</th><th align="center">Minutes at Full Rate</th></tr></thead><tbody><tr><td align="center">TeleMetrum v1.0</td><td align="center">8</td><td align="center">1MB</td><td align="center">20</td></tr><tr><td align="center">TeleMetrum v1.1 v1.2</td><td align="center">8</td><td align="center">2MB</td><td align="center">40</td></tr><tr><td align="center">TeleMetrum v2.0</td><td align="center">16</td><td align="center">8MB</td><td align="center">80</td></tr><tr><td align="center">TeleMini v1.0</td><td align="center">2</td><td align="center">5kB</td><td align="center">4</td></tr><tr><td align="center">TeleMini v2.0</td><td align="center">16</td><td align="center">1MB</td><td align="center">10</td></tr><tr><td align="center">EasyMini</td><td align="center">16</td><td align="center">1MB</td><td align="center">10</td></tr><tr><td align="center">TeleMega</td><td align="center">32</td><td align="center">8MB</td><td align="center">40</td></tr></tbody></table></div></div><br class="table-break"><p>
320 The on-board flash is partitioned into separate flight logs,
321 each of a fixed maximum size. Increase the maximum size of
322 each log and you reduce the number of flights that can be
323 stored. Decrease the size and you can store more flights.
325 Configuration data is also stored in the flash memory on
326 TeleMetrum v1.x, TeleMini and EasyMini. This consumes 64kB
327 of flash space. This configuration space is not available
328 for storing flight log data. TeleMetrum v2.0 and TeleMega
329 store configuration data in a bit of eeprom available within
330 the processor chip, leaving that space available in flash for
333 To compute the amount of space needed for a single flight, you
334 can multiply the expected ascent time (in seconds) by 100
335 times bytes-per-sample, multiply the expected descent time (in
336 seconds) by 10 times the bytes per sample and add the two
337 together. That will slightly under-estimate the storage (in
338 bytes) needed for the flight. For instance, a TeleMetrum v2.0 flight spending
339 20 seconds in ascent and 150 seconds in descent will take
340 about (20 * 1600) + (150 * 160) = 56000 bytes of storage. You
341 could store dozens of these flights in the on-board flash.
343 The default size allows for several flights on each flight
344 computer, except for TeleMini v1.0, which only holds data for a
345 single flight. You can adjust the size.
347 Altus Metrum flight computers will not overwrite existing
348 flight data, so be sure to download flight data and erase it
349 from the flight computer before it fills up. The flight
350 computer will still successfully control the flight even if it
351 cannot log data, so the only thing you will lose is the data.
352 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58383072"></a>7. Installation</h2></div></div></div><p>
353 A typical installation involves attaching
354 only a suitable battery, a single pole switch for
355 power on/off, and two pairs of wires connecting e-matches for the
356 apogee and main ejection charges. All Altus Metrum products are
357 designed for use with single-cell batteries with 3.7 volts
358 nominal. TeleMini v2.0 and EasyMini may also be used with other
359 batteries as long as they supply between 4 and 12 volts.
361 The battery connectors are a standard 2-pin JST connector and
362 match batteries sold by Spark Fun. These batteries are
363 single-cell Lithium Polymer batteries that nominally provide 3.7
364 volts. Other vendors sell similar batteries for RC aircraft
365 using mating connectors, however the polarity for those is
366 generally reversed from the batteries used by Altus Metrum
367 products. In particular, the Tenergy batteries supplied for use
368 in Featherweight flight computers are not compatible with Altus
369 Metrum flight computers or battery chargers. <span class="emphasis"><em>Check
370 polarity and voltage before connecting any battery not purchased
371 from Altus Metrum or Spark Fun.</em></span>
373 By default, we use the unregulated output of the battery directly
374 to fire ejection charges. This works marvelously with standard
375 low-current e-matches like the J-Tek from MJG Technologies, and with
376 Quest Q2G2 igniters. However, if you want or need to use a separate
377 pyro battery, check out the “External Pyro Battery” section in this
378 manual for instructions on how to wire that up. The altimeters are
379 designed to work with an external pyro battery of no more than 15 volts.
382 Ejection charges are wired directly to the screw terminal block
383 at the aft end of the altimeter. You'll need a very small straight
384 blade screwdriver for these screws, such as you might find in a
385 jeweler's screwdriver set.
387 Except for TeleMini v1.0, the flight computers also use the
388 screw terminal block for the power switch leads. On TeleMini v1.0,
389 the power switch leads are soldered directly to the board and
390 can be connected directly to a switch.
392 For most air-frames, the integrated antennas are more than
393 adequate. However, if you are installing in a carbon-fiber or
394 metal electronics bay which is opaque to RF signals, you may need to
395 use off-board external antennas instead. In this case, you can
396 replace the stock UHF antenna wire with an edge-launched SMA connector,
397 and, on TeleMetrum v1, you can unplug the integrated GPS
398 antenna and select an appropriate off-board GPS antenna with
399 cable terminating in a U.FL connector.
400 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp58389808"></a>Chapter 5. System Operation</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp58390448">1. Firmware Modes </a></span></dt><dt><span class="section"><a href="#idp58467152">2. GPS </a></span></dt><dt><span class="section"><a href="#idp58469936">3. Controlling An Altimeter Over The Radio Link</a></span></dt><dt><span class="section"><a href="#idp58481232">4. Ground Testing </a></span></dt><dt><span class="section"><a href="#idp58483984">5. Radio Link </a></span></dt><dt><span class="section"><a href="#idp58488672">6. Configurable Parameters</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58490416">6.1. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp58492464">6.2. Apogee Delay</a></span></dt><dt><span class="section"><a href="#idp58495056">6.3. Main Deployment Altitude</a></span></dt><dt><span class="section"><a href="#idp58496752">6.4. Maximum Flight Log</a></span></dt><dt><span class="section"><a href="#idp58498896">6.5. Ignite Mode</a></span></dt><dt><span class="section"><a href="#idp58501008">6.6. Pad Orientation</a></span></dt><dt><span class="section"><a href="#idp58502704">6.7. Configurable Pyro Channels</a></span></dt></dl></dd></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58390448"></a>1. Firmware Modes </h2></div></div></div><p>
401 The AltOS firmware build for the altimeters has two
402 fundamental modes, “idle” and “flight”. Which of these modes
403 the firmware operates in is determined at start up time. For
404 TeleMetrum and TeleMega, which have accelerometers, the mode is
405 controlled by the orientation of the
406 rocket (well, actually the board, of course...) at the time
407 power is switched on. If the rocket is “nose up”, then
408 the flight computer assumes it's on a rail or rod being prepared for
409 launch, so the firmware chooses flight mode. However, if the
410 rocket is more or less horizontal, the firmware instead enters
411 idle mode. Since TeleMini v2.0 and EasyMini don't have an
412 accelerometer we can use to determine orientation, “idle” mode
413 is selected if the board is connected via USB to a computer,
414 otherwise the board enters “flight” mode. TeleMini v1.0
415 selects “idle” mode if it receives a command packet within the
416 first five seconds of operation.
418 At power on, you will hear three beeps or see three flashes
419 (“S” in Morse code for start up) and then a pause while
420 the altimeter completes initialization and self test, and decides
421 which mode to enter next.
423 Here's a short summary of all of the modes and the beeping (or
424 flashing, in the case of TeleMini v1) that accompanies each
425 mode. In the description of the beeping pattern, “dit” means a
426 short beep while "dah" means a long beep (three times as
427 long). “Brap” means a long dissonant tone.
428 </p><div class="table"><a name="idp58391728"></a><p class="title"><b>Table 5.1. AltOS Modes</b></p><div class="table-contents"><table summary="AltOS Modes" border="1"><colgroup><col align="center" class="Mode Name"><col align="center" class="Letter"><col align="center" class="Beeps"><col align="center" class="Description"></colgroup><thead><tr><th align="center">Mode Name</th><th align="center">Abbreviation</th><th align="center">Beeps</th><th align="center">Description</th></tr></thead><tbody><tr><td align="center">Startup</td><td align="center">S</td><td align="center">dit dit dit</td><td align="center">
430 Calibrating sensors, detecting orientation.
432 </td></tr><tr><td align="center">Idle</td><td align="center">I</td><td align="center">dit dit</td><td align="center">
434 Ready to accept commands over USB or radio link.
436 </td></tr><tr><td align="center">Pad</td><td align="center">P</td><td align="center">dit dah dah dit</td><td align="center">
438 Waiting for launch. Not listening for commands.
440 </td></tr><tr><td align="center">Boost</td><td align="center">B</td><td align="center">dah dit dit dit</td><td align="center">
442 Accelerating upwards.
444 </td></tr><tr><td align="center">Fast</td><td align="center">F</td><td align="center">dit dit dah dit</td><td align="center">
446 Decellerating, but moving faster than 200m/s.
448 </td></tr><tr><td align="center">Coast</td><td align="center">C</td><td align="center">dah dit dah dit</td><td align="center">
450 Decellerating, moving slower than 200m/s
452 </td></tr><tr><td align="center">Drogue</td><td align="center">D</td><td align="center">dah dit dit</td><td align="center">
454 Descending after apogee. Above main height.
456 </td></tr><tr><td align="center">Main</td><td align="center">M</td><td align="center">dah dah</td><td align="center">
458 Descending. Below main height.
460 </td></tr><tr><td align="center">Landed</td><td align="center">L</td><td align="center">dit dah dit dit</td><td align="center">
462 Stable altitude for at least ten seconds.
464 </td></tr><tr><td align="center">Sensor error</td><td align="center">X</td><td align="center">dah dit dit dah</td><td align="center">
466 Error detected during sensor calibration.
468 </td></tr></tbody></table></div></div><p><br class="table-break">
470 In flight or “pad” mode, the altimeter engages the flight
471 state machine, goes into transmit-only mode to send telemetry,
472 and waits for launch to be detected. Flight mode is indicated
473 by an “di-dah-dah-dit” (“P” for pad) on the beeper or lights,
474 followed by beeps or flashes indicating the state of the
475 pyrotechnic igniter continuity. One beep/flash indicates
476 apogee continuity, two beeps/flashes indicate main continuity,
477 three beeps/flashes indicate both apogee and main continuity,
478 and one longer “brap” sound which is made by rapidly
479 alternating between two tones indicates no continuity. For a
480 dual deploy flight, make sure you're getting three beeps or
481 flashes before launching! For apogee-only or motor eject
482 flights, do what makes sense.
484 If idle mode is entered, you will hear an audible “di-dit” or
485 see two short flashes (“I” for idle), and the flight state
486 machine is disengaged, thus no ejection charges will fire.
487 The altimeters also listen for the radio link when in idle
488 mode for requests sent via TeleDongle. Commands can be issued
489 in idle mode over either USB or the radio link
490 equivalently. TeleMini v1.0 only has the radio link. Idle
491 mode is useful for configuring the altimeter, for extracting
492 data from the on-board storage chip after flight, and for
493 ground testing pyro charges.
495 In “Idle” and “Pad” modes, once the mode indication
496 beeps/flashes and continuity indication has been sent, if
497 there is no space available to log the flight in on-board
498 memory, the flight computer will emit a warbling tone (much
499 slower than the “no continuity tone”)
501 Here's a summary of all of the “pad” and “idle” mode indications.
502 </p><div class="table"><a name="idp58440960"></a><p class="title"><b>Table 5.2. Pad/Idle Indications</b></p><div class="table-contents"><table summary="Pad/Idle Indications" border="1"><colgroup><col align="center" class="Name"><col align="center" class="Beeps"><col align="center" class="Description"></colgroup><thead><tr><th align="center">Name</th><th align="center">Beeps</th><th align="center">Description</th></tr></thead><tbody><tr><td align="center">Neither</td><td align="center">brap</td><td align="center">
504 No continuity detected on either apogee or main
507 </td></tr><tr><td align="center">Apogee</td><td align="center">dit</td><td align="center">
509 Continuity detected only on apogee igniter.
511 </td></tr><tr><td align="center">Main</td><td align="center">dit dit</td><td align="center">
513 Continuity detected only on main igniter.
515 </td></tr><tr><td align="center">Both</td><td align="center">dit dit dit</td><td align="center">
517 Continuity detected on both igniters.
519 </td></tr><tr><td align="center">Storage Full</td><td align="center">warble</td><td align="center">
521 On-board data logging storage is full. This will
522 not prevent the flight computer from safely
523 controlling the flight or transmitting telemetry
524 signals, but no record of the flight will be
525 stored in on-board flash.
527 </td></tr></tbody></table></div></div><p><br class="table-break">
529 Once landed, the flight computer will signal that by emitting
530 the “Landed” sound described above, after which it will beep
531 out the apogee height (in meters). Each digit is represented
532 by a sequence of short “dit” beeps, with a pause between
533 digits. A zero digit is represented with one long “dah”
534 beep. The flight computer will continue to report landed mode
535 and beep out the maximum height until turned off.
537 One “neat trick” of particular value when TeleMetrum or TeleMega are used with
538 very large air-frames, is that you can power the board up while the
539 rocket is horizontal, such that it comes up in idle mode. Then you can
540 raise the air-frame to launch position, and issue a 'reset' command
541 via TeleDongle over the radio link to cause the altimeter to reboot and
542 come up in flight mode. This is much safer than standing on the top
543 step of a rickety step-ladder or hanging off the side of a launch
544 tower with a screw-driver trying to turn on your avionics before
547 TeleMini v1.0 is configured solely via the radio link. Of course, that
548 means you need to know the TeleMini radio configuration values
549 or you won't be able to communicate with it. For situations
550 when you don't have the radio configuration values, TeleMini v1.0
551 offers an 'emergency recovery' mode. In this mode, TeleMini is
552 configured as follows:
553 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
554 Sets the radio frequency to 434.550MHz
555 </p></li><li class="listitem"><p>
556 Sets the radio calibration back to the factory value.
557 </p></li><li class="listitem"><p>
558 Sets the callsign to N0CALL
559 </p></li><li class="listitem"><p>
560 Does not go to 'pad' mode after five seconds.
561 </p></li></ul></div><p>
563 To get into 'emergency recovery' mode, first find the row of
564 four small holes opposite the switch wiring. Using a short
565 piece of small gauge wire, connect the outer two holes
566 together, then power TeleMini up. Once the red LED is lit,
567 disconnect the wire and the board should signal that it's in
568 'idle' mode after the initial five second startup period.
569 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58467152"></a>2. GPS </h2></div></div></div><p>
570 TeleMetrum and TeleMega include a complete GPS receiver. A
571 complete explanation of how GPS works is beyond the scope of
572 this manual, but the bottom line is that the GPS receiver
573 needs to lock onto at least four satellites to obtain a solid
574 3 dimensional position fix and know what time it is.
576 The flight computers provide backup power to the GPS chip any time a
577 battery is connected. This allows the receiver to “warm start” on
578 the launch rail much faster than if every power-on were a GPS
579 “cold start”. In typical operations, powering up
580 on the flight line in idle mode while performing final air-frame
581 preparation will be sufficient to allow the GPS receiver to cold
582 start and acquire lock. Then the board can be powered down during
583 RSO review and installation on a launch rod or rail. When the board
584 is turned back on, the GPS system should lock very quickly, typically
585 long before igniter installation and return to the flight line are
587 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58469936"></a>3. Controlling An Altimeter Over The Radio Link</h2></div></div></div><p>
588 One of the unique features of the Altus Metrum system is the
589 ability to create a two way command link between TeleDongle
590 and an altimeter using the digital radio transceivers
591 built into each device. This allows you to interact with the
592 altimeter from afar, as if it were directly connected to the
595 Any operation which can be performed with a flight computer can
596 either be done with the device directly connected to the
597 computer via the USB cable, or through the radio
598 link. TeleMini v1.0 doesn't provide a USB connector and so it is
599 always communicated with over radio. Select the appropriate
600 TeleDongle device when the list of devices is presented and
601 AltosUI will interact with an altimeter over the radio link.
603 One oddity in the current interface is how AltosUI selects the
604 frequency for radio communications. Instead of providing
605 an interface to specifically configure the frequency, it uses
606 whatever frequency was most recently selected for the target
607 TeleDongle device in Monitor Flight mode. If you haven't ever
608 used that mode with the TeleDongle in question, select the
609 Monitor Flight button from the top level UI, and pick the
610 appropriate TeleDongle device. Once the flight monitoring
611 window is open, select the desired frequency and then close it
612 down again. All radio communications will now use that frequency.
613 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
614 Save Flight Data—Recover flight data from the rocket without
616 </p></li><li class="listitem"><p>
617 Configure altimeter apogee delays, main deploy heights
618 and additional pyro event conditions
619 to respond to changing launch conditions. You can also
620 'reboot' the altimeter. Use this to remotely enable the
621 flight computer by turning TeleMetrum or TeleMega on in “idle” mode,
622 then once the air-frame is oriented for launch, you can
623 reboot the altimeter and have it restart in pad mode
624 without having to climb the scary ladder.
625 </p></li><li class="listitem"><p>
626 Fire Igniters—Test your deployment charges without snaking
627 wires out through holes in the air-frame. Simply assemble the
628 rocket as if for flight with the apogee and main charges
629 loaded, then remotely command the altimeter to fire the
631 </p></li></ul></div><p>
632 Operation over the radio link for configuring an altimeter, ground
633 testing igniters, and so forth uses the same RF frequencies as flight
634 telemetry. To configure the desired TeleDongle frequency, select
635 the monitor flight tab, then use the frequency selector and
636 close the window before performing other desired radio operations.
638 The flight computers only enable radio commanding in 'idle' mode.
639 TeleMetrum and TeleMega use the accelerometer to detect which orientation they
640 start up in, so make sure you have the flight computer lying horizontally when you turn
641 it on. Otherwise, it will start in 'pad' mode ready for
642 flight, and will not be listening for command packets from TeleDongle.
644 TeleMini listens for a command packet for five seconds after
645 first being turned on, if it doesn't hear anything, it enters
646 'pad' mode, ready for flight and will no longer listen for
647 command packets. The easiest way to connect to TeleMini is to
648 initiate the command and select the TeleDongle device. At this
649 point, the TeleDongle will be attempting to communicate with
650 the TeleMini. Now turn TeleMini on, and it should immediately
651 start communicating with the TeleDongle and the desired
652 operation can be performed.
654 You can monitor the operation of the radio link by watching the
655 lights on the devices. The red LED will flash each time a packet
656 is transmitted, while the green LED will light up on TeleDongle when
657 it is waiting to receive a packet from the altimeter.
658 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58481232"></a>4. Ground Testing </h2></div></div></div><p>
659 An important aspect of preparing a rocket using electronic deployment
660 for flight is ground testing the recovery system. Thanks
661 to the bi-directional radio link central to the Altus Metrum system,
662 this can be accomplished in a TeleMega, TeleMetrum or TeleMini equipped rocket
663 with less work than you may be accustomed to with other systems. It
666 Just prep the rocket for flight, then power up the altimeter
667 in “idle” mode (placing air-frame horizontal for TeleMetrum or TeleMega, or
668 selecting the Configure Altimeter tab for TeleMini). This will cause
669 the firmware to go into “idle” mode, in which the normal flight
670 state machine is disabled and charges will not fire without
671 manual command. You can now command the altimeter to fire the apogee
672 or main charges from a safe distance using your computer and
673 TeleDongle and the Fire Igniter tab to complete ejection testing.
674 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58483984"></a>5. Radio Link </h2></div></div></div><p>
675 Our flight computers all incorporate an RF transceiver, but
676 it's not a full duplex system... each end can only be transmitting or
677 receiving at any given moment. So we had to decide how to manage the
680 By design, the altimeter firmware listens for the radio link when
681 it's in “idle mode”, which
682 allows us to use the radio link to configure the rocket, do things like
683 ejection tests, and extract data after a flight without having to
684 crack open the air-frame. However, when the board is in “flight
685 mode”, the altimeter only
686 transmits and doesn't listen at all. That's because we want to put
687 ultimate priority on event detection and getting telemetry out of
689 the radio in case the rocket crashes and we aren't able to extract
692 We don't generally use a 'normal packet radio' mode like APRS
693 because they're just too inefficient. The GFSK modulation we
694 use is FSK with the base-band pulses passed through a Gaussian
695 filter before they go into the modulator to limit the
696 transmitted bandwidth. When combined with forward error
697 correction and interleaving, this allows us to have a very
698 robust 19.2 kilobit data link with only 10-40 milliwatts of
699 transmit power, a whip antenna in the rocket, and a hand-held
700 Yagi on the ground. We've had flights to above 21k feet AGL
701 with great reception, and calculations suggest we should be
702 good to well over 40k feet AGL with a 5-element yagi on the
703 ground with our 10mW units and over 100k feet AGL with the
704 40mW devices. We hope to fly boards to higher altitudes over
705 time, and would of course appreciate customer feedback on
706 performance in higher altitude flights!
708 TeleMetrum v2.0 and TeleMega can send APRS if desired, and the
709 interval between APRS packets can be configured. As each APRS
710 packet takes a full second to transmit, we recommend an
711 interval of at least 5 seconds to avoid consuming too much
712 battery power or radio channel bandwidth.
713 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58488672"></a>6. Configurable Parameters</h2></div></div></div><p>
714 Configuring an Altus Metrum altimeter for flight is very
715 simple. Even on our baro-only TeleMini and EasyMini boards, the use of a Kalman
716 filter means there is no need to set a “mach delay”. The few
717 configurable parameters can all be set using AltosUI over USB or
718 or radio link via TeleDongle.
719 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58490416"></a>6.1. Radio Frequency</h3></div></div></div><p>
720 Altus Metrum boards support radio frequencies in the 70cm
721 band. By default, the configuration interface provides a
722 list of 10 “standard” frequencies in 100kHz channels starting at
723 434.550MHz. However, the firmware supports use of
724 any 50kHz multiple within the 70cm band. At any given
725 launch, we highly recommend coordinating when and by whom each
726 frequency will be used to avoid interference. And of course, both
727 altimeter and TeleDongle must be configured to the same
728 frequency to successfully communicate with each other.
729 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58492464"></a>6.2. Apogee Delay</h3></div></div></div><p>
730 Apogee delay is the number of seconds after the altimeter detects flight
731 apogee that the drogue charge should be fired. In most cases, this
732 should be left at the default of 0. However, if you are flying
733 redundant electronics such as for an L3 certification, you may wish
734 to set one of your altimeters to a positive delay so that both
735 primary and backup pyrotechnic charges do not fire simultaneously.
737 The Altus Metrum apogee detection algorithm fires exactly at
738 apogee. If you are also flying an altimeter like the
739 PerfectFlite MAWD, which only supports selecting 0 or 1
740 seconds of apogee delay, you may wish to set the MAWD to 0
741 seconds delay and set the TeleMetrum to fire your backup 2
742 or 3 seconds later to avoid any chance of both charges
743 firing simultaneously. We've flown several air-frames this
744 way quite happily, including Keith's successful L3 cert.
745 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58495056"></a>6.3. Main Deployment Altitude</h3></div></div></div><p>
746 By default, the altimeter will fire the main deployment charge at an
747 elevation of 250 meters (about 820 feet) above ground. We think this
748 is a good elevation for most air-frames, but feel free to change this
749 to suit. In particular, if you are flying two altimeters, you may
751 deployment elevation for the backup altimeter to be something lower
752 than the primary so that both pyrotechnic charges don't fire
754 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58496752"></a>6.4. Maximum Flight Log</h3></div></div></div><p>
755 Changing this value will set the maximum amount of flight
756 log storage that an individual flight will use. The
757 available storage is divided into as many flights of the
758 specified size as can fit in the available space. You can
759 download and erase individual flight logs. If you fill up
760 the available storage, future flights will not get logged
761 until you erase some of the stored ones.
763 Even though our flight computers (except TeleMini v1.0) can store
764 multiple flights, we strongly recommend downloading and saving
765 flight data after each flight.
766 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58498896"></a>6.5. Ignite Mode</h3></div></div></div><p>
767 Instead of firing one charge at apogee and another charge at
768 a fixed height above the ground, you can configure the
769 altimeter to fire both at apogee or both during
770 descent. This was added to support an airframe Bdale designed that
771 had two altimeters, one in the fin can and one in the nose.
773 Providing the ability to use both igniters for apogee or
774 main allows some level of redundancy without needing two
775 flight computers. In Redundant Apogee or Redundant Main
776 mode, the two charges will be fired two seconds apart.
777 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58501008"></a>6.6. Pad Orientation</h3></div></div></div><p>
778 TeleMetrum and TeleMega measure acceleration along the axis
779 of the board. Which way the board is oriented affects the
780 sign of the acceleration value. Instead of trying to guess
781 which way the board is mounted in the air frame, the
782 altimeter must be explicitly configured for either Antenna
783 Up or Antenna Down. The default, Antenna Up, expects the end
784 of the board connected to the 70cm antenna to be nearest the
785 nose of the rocket, with the end containing the screw
786 terminals nearest the tail.
787 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58502704"></a>6.7. Configurable Pyro Channels</h3></div></div></div><p>
788 In addition to the usual Apogee and Main pyro channels,
789 TeleMega has four additional channels that can be configured
790 to activate when various flight conditions are
791 satisfied. You can select as many conditions as necessary;
792 all of them must be met in order to activate the
793 channel. The conditions available are:
794 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
795 Acceleration away from the ground. Select a value, and
796 then choose whether acceleration should be above or
797 below that value. Acceleration is positive upwards, so
798 accelerating towards the ground would produce negative
799 numbers. Acceleration during descent is noisy and
800 inaccurate, so be careful when using it during these
801 phases of the flight.
802 </p></li><li class="listitem"><p>
803 Vertical speed. Select a value, and then choose whether
804 vertical speed should be above or below that
805 value. Speed is positive upwards, so moving towards the
806 ground would produce negative numbers. Speed during
807 descent is a bit noisy and so be careful when using it
808 during these phases of the flight.
809 </p></li><li class="listitem"><p>
810 Height. Select a value, and then choose whether the
811 height above the launch pad should be above or below
813 </p></li><li class="listitem"><p>
814 Orientation. TeleMega contains a 3-axis gyroscope and
815 accelerometer which is used to measure the current
816 angle. Note that this angle is not the change in angle
817 from the launch pad, but rather absolute relative to
818 gravity; the 3-axis accelerometer is used to compute the
819 angle of the rocket on the launch pad and initialize the
820 system. Because this value is computed by integrating
821 rate gyros, it gets progressively less accurate as the
822 flight goes on. It should have an accumulated error of
823 less than 0.2°/second (after 10 seconds of flight, the
824 error should be less than 2°).
826 The usual use of the orientation configuration is to
827 ensure that the rocket is traveling mostly upwards when
828 deciding whether to ignite air starts or additional
829 stages. For that, choose a reasonable maximum angle
830 (like 20°) and set the motor igniter to require an angle
831 of less than that value.
832 </p></li><li class="listitem"><p>
833 Flight Time. Time since boost was detected. Select a
834 value and choose whether to activate the pyro channel
835 before or after that amount of time.
836 </p></li><li class="listitem"><p>
837 Ascending. A simple test saying whether the rocket is
838 going up or not. This is exactly equivalent to testing
839 whether the speed is > 0.
840 </p></li><li class="listitem"><p>
841 Descending. A simple test saying whether the rocket is
842 going down or not. This is exactly equivalent to testing
843 whether the speed is < 0.
844 </p></li><li class="listitem"><p>
845 After Motor. The flight software counts each time the
846 rocket starts accelerating (presumably due to a motor or
847 motors igniting). Use this value to count ignitions for
848 multi-staged or multi-airstart launches.
849 </p></li><li class="listitem"><p>
850 Delay. This value doesn't perform any checks, instead it
851 inserts a delay between the time when the other
852 parameters become true and when the pyro channel is
854 </p></li><li class="listitem"><p>
855 Flight State. The flight software tracks the flight
856 through a sequence of states:
857 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
858 Boost. The motor has lit and the rocket is
859 accelerating upwards.
860 </p></li><li class="listitem"><p>
861 Fast. The motor has burned out and the rocket is
862 descellerating, but it is going faster than 200m/s.
863 </p></li><li class="listitem"><p>
864 Coast. The rocket is still moving upwards and
865 decelerating, but the speed is less than 200m/s.
866 </p></li><li class="listitem"><p>
867 Drogue. The rocket has reached apogee and is heading
868 back down, but is above the configured Main
870 </p></li><li class="listitem"><p>
871 Main. The rocket is still descending, and is below
873 </p></li><li class="listitem"><p>
874 Landed. The rocket is no longer moving.
875 </p></li></ol></div><p>
877 You can select a state to limit when the pyro channel
878 may activate; note that the check is based on when the
879 rocket transitions <span class="emphasis"><em>into</em></span> the state, and so checking for
880 “greater than Boost” means that the rocket is currently
881 in boost or some later state.
883 When a motor burns out, the rocket enters either Fast or
884 Coast state (depending on how fast it is moving). If the
885 computer detects upwards acceleration again, it will
886 move back to Boost state.
887 </p></li></ul></div></div></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp58525184"></a>Chapter 6. AltosUI</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp58528800">1. Monitor Flight</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58541520">1.1. Launch Pad</a></span></dt><dt><span class="section"><a href="#idp58557152">1.2. Ascent</a></span></dt><dt><span class="section"><a href="#idp58562608">1.3. Descent</a></span></dt><dt><span class="section"><a href="#idp58569472">1.4. Landed</a></span></dt><dt><span class="section"><a href="#idp58575904">1.5. Table</a></span></dt><dt><span class="section"><a href="#idp58579488">1.6. Site Map</a></span></dt></dl></dd><dt><span class="section"><a href="#idp58585152">2. Save Flight Data</a></span></dt><dt><span class="section"><a href="#idp58589632">3. Replay Flight</a></span></dt><dt><span class="section"><a href="#idp58591664">4. Graph Data</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58594048">4.1. Flight Graph</a></span></dt><dt><span class="section"><a href="#idp58598496">4.2. Configure Graph</a></span></dt><dt><span class="section"><a href="#idp58602160">4.3. Flight Statistics</a></span></dt><dt><span class="section"><a href="#idp58605680">4.4. Map</a></span></dt></dl></dd><dt><span class="section"><a href="#idp58609536">5. Export Data</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58611648">5.1. Comma Separated Value Format</a></span></dt><dt><span class="section"><a href="#idp58614000">5.2. Keyhole Markup Language (for Google Earth)</a></span></dt></dl></dd><dt><span class="section"><a href="#idp58615488">6. Configure Altimeter</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58627792">6.1. Main Deploy Altitude</a></span></dt><dt><span class="section"><a href="#idp58629360">6.2. Apogee Delay</a></span></dt><dt><span class="section"><a href="#idp58630976">6.3. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp58632480">6.4. RF Calibration</a></span></dt><dt><span class="section"><a href="#idp58634128">6.5. Telemetry/RDF/APRS Enable</a></span></dt><dt><span class="section"><a href="#idp58635424">6.6. APRS Interval</a></span></dt><dt><span class="section"><a href="#idp58636928">6.7. Callsign</a></span></dt><dt><span class="section"><a href="#idp58638240">6.8. Maximum Flight Log Size</a></span></dt><dt><span class="section"><a href="#idp58639680">6.9. Ignite Mode</a></span></dt><dt><span class="section"><a href="#idp58646672">6.10. Pad Orientation</a></span></dt><dt><span class="section"><a href="#idp58651888">6.11. Configure Pyro Channels</a></span></dt></dl></dd><dt><span class="section"><a href="#idp58657696">7. Configure AltosUI</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58661200">7.1. Voice Settings</a></span></dt><dt><span class="section"><a href="#idp58666224">7.2. Log Directory</a></span></dt><dt><span class="section"><a href="#idp58668224">7.3. Callsign</a></span></dt><dt><span class="section"><a href="#idp58670464">7.4. Imperial Units</a></span></dt><dt><span class="section"><a href="#idp58671968">7.5. Font Size</a></span></dt><dt><span class="section"><a href="#idp58673248">7.6. Serial Debug</a></span></dt><dt><span class="section"><a href="#idp58674752">7.7. Manage Frequencies</a></span></dt></dl></dd><dt><span class="section"><a href="#idp58676384">8. Configure Groundstation</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58687504">8.1. Frequency</a></span></dt><dt><span class="section"><a href="#idp58689072">8.2. Radio Calibration</a></span></dt></dl></dd><dt><span class="section"><a href="#idp58690704">9. Flash Image</a></span></dt><dt><span class="section"><a href="#idp58692336">10. Fire Igniter</a></span></dt><dt><span class="section"><a href="#idp58697968">11. Scan Channels</a></span></dt><dt><span class="section"><a href="#idp58701824">12. Load Maps</a></span></dt><dt><span class="section"><a href="#idp58707520">13. Monitor Idle</a></span></dt></dl></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="altosui.png" width="495"></td></tr></table></div></div><p>
888 The AltosUI program provides a graphical user interface for
889 interacting with the Altus Metrum product family. AltosUI can
890 monitor telemetry data, configure devices and many other
891 tasks. The primary interface window provides a selection of
892 buttons, one for each major activity in the system. This chapter
893 is split into sections, each of which documents one of the tasks
894 provided from the top-level toolbar.
895 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58528800"></a>1. Monitor Flight</h2></div><div><h3 class="subtitle">Receive, Record and Display Telemetry Data</h3></div></div></div><p>
896 Selecting this item brings up a dialog box listing all of the
897 connected TeleDongle devices. When you choose one of these,
898 AltosUI will create a window to display telemetry data as
899 received by the selected TeleDongle device.
900 </p><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="315"><tr><td><img src="device-selection.png" width="315"></td></tr></table></div></div><p>
901 All telemetry data received are automatically recorded in
902 suitable log files. The name of the files includes the current
903 date and rocket serial and flight numbers.
905 The radio frequency being monitored by the TeleDongle device is
906 displayed at the top of the window. You can configure the
907 frequency by clicking on the frequency box and selecting the desired
908 frequency. AltosUI remembers the last frequency selected for each
909 TeleDongle and selects that automatically the next time you use
912 Below the TeleDongle frequency selector, the window contains a few
913 significant pieces of information about the altimeter providing
914 the telemetry data stream:
915 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>The configured call-sign</p></li><li class="listitem"><p>The device serial number</p></li><li class="listitem"><p>The flight number. Each altimeter remembers how many
917 </p></li><li class="listitem"><p>
918 The rocket flight state. Each flight passes through several
919 states including Pad, Boost, Fast, Coast, Drogue, Main and
921 </p></li><li class="listitem"><p>
922 The Received Signal Strength Indicator value. This lets
923 you know how strong a signal TeleDongle is receiving. The
924 radio inside TeleDongle operates down to about -99dBm;
925 weaker signals may not be receivable. The packet link uses
926 error detection and correction techniques which prevent
927 incorrect data from being reported.
928 </p></li><li class="listitem"><p>
929 The age of the displayed data, in seconds since the last
930 successfully received telemetry packet. In normal operation
931 this will stay in the low single digits. If the number starts
932 counting up, then you are no longer receiving data over the radio
933 link from the flight computer.
934 </p></li></ul></div><p>
935 Finally, the largest portion of the window contains a set of
936 tabs, each of which contain some information about the rocket.
937 They're arranged in 'flight order' so that as the flight
938 progresses, the selected tab automatically switches to display
939 data relevant to the current state of the flight. You can select
940 other tabs at any time. The final 'table' tab displays all of
941 the raw telemetry values in one place in a spreadsheet-like format.
942 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58541520"></a>1.1. Launch Pad</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="launch-pad.png" width="495"></td></tr></table></div></div><p>
943 The 'Launch Pad' tab shows information used to decide when the
944 rocket is ready for flight. The first elements include red/green
945 indicators, if any of these is red, you'll want to evaluate
946 whether the rocket is ready to launch:
947 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Battery Voltage</span></dt><dd><p>
948 This indicates whether the Li-Po battery powering the
949 flight computer has sufficient charge to last for
950 the duration of the flight. A value of more than
951 3.8V is required for a 'GO' status.
952 </p></dd><dt><span class="term">Apogee Igniter Voltage</span></dt><dd><p>
953 This indicates whether the apogee
954 igniter has continuity. If the igniter has a low
955 resistance, then the voltage measured here will be close
956 to the Li-Po battery voltage. A value greater than 3.2V is
957 required for a 'GO' status.
958 </p></dd><dt><span class="term">Main Igniter Voltage</span></dt><dd><p>
959 This indicates whether the main
960 igniter has continuity. If the igniter has a low
961 resistance, then the voltage measured here will be close
962 to the Li-Po battery voltage. A value greater than 3.2V is
963 required for a 'GO' status.
964 </p></dd><dt><span class="term">On-board Data Logging</span></dt><dd><p>
965 This indicates whether there is
966 space remaining on-board to store flight data for the
967 upcoming flight. If you've downloaded data, but failed
968 to erase flights, there may not be any space
969 left. Most of our flight computers can store multiple
970 flights, depending on the configured maximum flight log
971 size. TeleMini v1.0 stores only a single flight, so it
973 downloaded and erased after each flight to capture
974 data. This only affects on-board flight logging; the
975 altimeter will still transmit telemetry and fire
976 ejection charges at the proper times even if the flight
977 data storage is full.
978 </p></dd><dt><span class="term">GPS Locked</span></dt><dd><p>
979 For a TeleMetrum or TeleMega device, this indicates whether the GPS receiver is
980 currently able to compute position information. GPS requires
981 at least 4 satellites to compute an accurate position.
982 </p></dd><dt><span class="term">GPS Ready</span></dt><dd><p>
983 For a TeleMetrum or TeleMega device, this indicates whether GPS has reported at least
984 10 consecutive positions without losing lock. This ensures
985 that the GPS receiver has reliable reception from the
987 </p></dd></dl></div><p>
989 The Launchpad tab also shows the computed launch pad position
990 and altitude, averaging many reported positions to improve the
992 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58557152"></a>1.2. Ascent</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="ascent.png" width="495"></td></tr></table></div></div><p>
993 This tab is shown during Boost, Fast and Coast
994 phases. The information displayed here helps monitor the
995 rocket as it heads towards apogee.
997 The height, speed and acceleration are shown along with the
998 maximum values for each of them. This allows you to quickly
999 answer the most commonly asked questions you'll hear during
1002 The current latitude and longitude reported by the GPS are
1003 also shown. Note that under high acceleration, these values
1004 may not get updated as the GPS receiver loses position
1005 fix. Once the rocket starts coasting, the receiver should
1006 start reporting position again.
1008 Finally, the current igniter voltages are reported as in the
1009 Launch Pad tab. This can help diagnose deployment failures
1010 caused by wiring which comes loose under high acceleration.
1011 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58562608"></a>1.3. Descent</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="descent.png" width="495"></td></tr></table></div></div><p>
1012 Once the rocket has reached apogee and (we hope) activated the
1013 apogee charge, attention switches to tracking the rocket on
1014 the way back to the ground, and for dual-deploy flights,
1015 waiting for the main charge to fire.
1017 To monitor whether the apogee charge operated correctly, the
1018 current descent rate is reported along with the current
1019 height. Good descent rates vary based on the choice of recovery
1020 components, but generally range from 15-30m/s on drogue and should
1021 be below 10m/s when under the main parachute in a dual-deploy flight.
1023 With GPS-equipped flight computers, you can locate the rocket in the
1024 sky using the elevation and bearing information to figure
1025 out where to look. Elevation is in degrees above the
1026 horizon. Bearing is reported in degrees relative to true
1027 north. Range can help figure out how big the rocket will
1028 appear. Ground Distance shows how far it is to a point
1029 directly under the rocket and can help figure out where the
1030 rocket is likely to land. Note that all of these values are
1031 relative to the pad location. If the elevation is near 90°,
1032 the rocket is over the pad, not over you.
1034 Finally, the igniter voltages are reported in this tab as
1035 well, both to monitor the main charge as well as to see what
1036 the status of the apogee charge is. Note that some commercial
1037 e-matches are designed to retain continuity even after being
1038 fired, and will continue to show as green or return from red to
1040 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58569472"></a>1.4. Landed</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="landed.png" width="495"></td></tr></table></div></div><p>
1041 Once the rocket is on the ground, attention switches to
1042 recovery. While the radio signal is often lost once the
1043 rocket is on the ground, the last reported GPS position is
1044 generally within a short distance of the actual landing location.
1046 The last reported GPS position is reported both by
1047 latitude and longitude as well as a bearing and distance from
1048 the launch pad. The distance should give you a good idea of
1049 whether to walk or hitch a ride. Take the reported
1050 latitude and longitude and enter them into your hand-held GPS
1051 unit and have that compute a track to the landing location.
1053 Our flight computers will continue to transmit RDF
1054 tones after landing, allowing you to locate the rocket by
1055 following the radio signal if necessary. You may need to get
1056 away from the clutter of the flight line, or even get up on
1057 a hill (or your neighbor's RV roof) to receive the RDF signal.
1059 The maximum height, speed and acceleration reported
1060 during the flight are displayed for your admiring observers.
1061 The accuracy of these immediate values depends on the quality
1062 of your radio link and how many packets were received.
1063 Recovering the on-board data after flight may yield
1064 more precise results.
1066 To get more detailed information about the flight, you can
1067 click on the 'Graph Flight' button which will bring up a
1068 graph window for the current flight.
1069 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58575904"></a>1.5. Table</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="table.png" width="495"></td></tr></table></div></div><p>
1070 The table view shows all of the data available from the
1071 flight computer. Probably the most useful data on
1072 this tab is the detailed GPS information, which includes
1073 horizontal dilution of precision information, and
1074 information about the signal being received from the satellites.
1075 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58579488"></a>1.6. Site Map</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="site-map.png" width="495"></td></tr></table></div></div><p>
1076 When the TeleMetrum has a GPS fix, the Site Map tab will map
1077 the rocket's position to make it easier for you to locate the
1078 rocket, both while it is in the air, and when it has landed. The
1079 rocket's state is indicated by color: white for pad, red for
1080 boost, pink for fast, yellow for coast, light blue for drogue,
1081 dark blue for main, and black for landed.
1083 The map's scale is approximately 3m (10ft) per pixel. The map
1084 can be dragged using the left mouse button. The map will attempt
1085 to keep the rocket roughly centered while data is being received.
1087 Images are fetched automatically via the Google Maps Static API,
1088 and cached on disk for reuse. If map images cannot be downloaded,
1089 the rocket's path will be traced on a dark gray background
1092 You can pre-load images for your favorite launch sites
1093 before you leave home; check out the 'Preload Maps' section below.
1094 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58585152"></a>2. Save Flight Data</h2></div></div></div><p>
1095 The altimeter records flight data to its internal flash memory.
1096 TeleMetrum data is recorded at a much higher rate than the telemetry
1097 system can handle, and is not subject to radio drop-outs. As
1098 such, it provides a more complete and precise record of the
1099 flight. The 'Save Flight Data' button allows you to read the
1100 flash memory and write it to disk.
1102 Clicking on the 'Save Flight Data' button brings up a list of
1103 connected flight computers and TeleDongle devices. If you select a
1104 flight computer, the flight data will be downloaded from that
1105 device directly. If you select a TeleDongle device, flight data
1106 will be downloaded from a flight computer over radio link via the
1107 specified TeleDongle. See the chapter on Controlling An Altimeter
1108 Over The Radio Link for more information.
1110 After the device has been selected, a dialog showing the
1111 flight data saved in the device will be shown allowing you to
1112 select which flights to download and which to delete. With
1113 version 0.9 or newer firmware, you must erase flights in order
1114 for the space they consume to be reused by another
1115 flight. This prevents accidentally losing flight data
1116 if you neglect to download data before flying again. Note that
1117 if there is no more space available in the device, then no
1118 data will be recorded during the next flight.
1120 The file name for each flight log is computed automatically
1121 from the recorded flight date, altimeter serial number and
1122 flight number information.
1123 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58589632"></a>3. Replay Flight</h2></div></div></div><p>
1124 Select this button and you are prompted to select a flight
1125 record file, either a .telem file recording telemetry data or a
1126 .eeprom file containing flight data saved from the altimeter
1129 Once a flight record is selected, the flight monitor interface
1130 is displayed and the flight is re-enacted in real time. Check
1131 the Monitor Flight chapter above to learn how this window operates.
1132 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58591664"></a>4. Graph Data</h2></div></div></div><p>
1133 Select this button and you are prompted to select a flight
1134 record file, either a .telem file recording telemetry data or a
1135 .eeprom file containing flight data saved from
1138 Note that telemetry files will generally produce poor graphs
1139 due to the lower sampling rate and missed telemetry packets.
1140 Use saved flight data in .eeprom files for graphing where possible.
1142 Once a flight record is selected, a window with multiple tabs is
1144 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58594048"></a>4.1. Flight Graph</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="graph.png" width="495"></td></tr></table></div></div><p>
1145 By default, the graph contains acceleration (blue),
1146 velocity (green) and altitude (red).
1148 The graph can be zoomed into a particular area by clicking and
1149 dragging down and to the right. Once zoomed, the graph can be
1150 reset by clicking and dragging up and to the left. Holding down
1151 control and clicking and dragging allows the graph to be panned.
1152 The right mouse button causes a pop-up menu to be displayed, giving
1153 you the option save or print the plot.
1154 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58598496"></a>4.2. Configure Graph</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="graph-configure.png" width="495"></td></tr></table></div></div><p>
1155 This selects which graph elements to show, and, at the
1156 very bottom, lets you switch between metric and
1158 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58602160"></a>4.3. Flight Statistics</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="graph-stats.png" width="495"></td></tr></table></div></div><p>
1159 Shows overall data computed from the flight.
1160 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58605680"></a>4.4. Map</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="graph-map.png" width="495"></td></tr></table></div></div><p>
1161 Shows a satellite image of the flight area overlaid
1162 with the path of the flight. The red concentric
1163 circles mark the launch pad, the black concentric
1164 circles mark the landing location.
1165 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58609536"></a>5. Export Data</h2></div></div></div><p>
1166 This tool takes the raw data files and makes them available for
1167 external analysis. When you select this button, you are prompted to
1168 select a flight data file, which can be either a .eeprom or .telem.
1169 The .eeprom files contain higher resolution and more continuous data,
1170 while .telem files contain receiver signal strength information.
1171 Next, a second dialog appears which is used to select
1172 where to write the resulting file. It has a selector to choose
1173 between CSV and KML file formats.
1174 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58611648"></a>5.1. Comma Separated Value Format</h3></div></div></div><p>
1175 This is a text file containing the data in a form suitable for
1176 import into a spreadsheet or other external data analysis
1177 tool. The first few lines of the file contain the version and
1178 configuration information from the altimeter, then
1179 there is a single header line which labels all of the
1180 fields. All of these lines start with a '#' character which
1181 many tools can be configured to skip over.
1183 The remaining lines of the file contain the data, with each
1184 field separated by a comma and at least one space. All of
1185 the sensor values are converted to standard units, with the
1186 barometric data reported in both pressure, altitude and
1187 height above pad units.
1188 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58614000"></a>5.2. Keyhole Markup Language (for Google Earth)</h3></div></div></div><p>
1189 This is the format used by Google Earth to provide an overlay
1190 within that application. With this, you can use Google Earth to
1191 see the whole flight path in 3D.
1192 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58615488"></a>6. Configure Altimeter</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="270"><tr><td><img src="configure-altimeter.png" width="270"></td></tr></table></div></div><p>
1193 Select this button and then select either an altimeter or
1194 TeleDongle Device from the list provided. Selecting a TeleDongle
1195 device will use the radio link to configure a remote altimeter.
1197 The first few lines of the dialog provide information about the
1198 connected device, including the product name,
1199 software version and hardware serial number. Below that are the
1200 individual configuration entries.
1202 At the bottom of the dialog, there are four buttons:
1203 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Save</span></dt><dd><p>
1204 This writes any changes to the
1205 configuration parameter block in flash memory. If you don't
1206 press this button, any changes you make will be lost.
1207 </p></dd><dt><span class="term">Reset</span></dt><dd><p>
1208 This resets the dialog to the most recently saved values,
1209 erasing any changes you have made.
1210 </p></dd><dt><span class="term">Reboot</span></dt><dd><p>
1211 This reboots the device. Use this to
1212 switch from idle to pad mode by rebooting once the rocket is
1213 oriented for flight, or to confirm changes you think you saved
1215 </p></dd><dt><span class="term">Close</span></dt><dd><p>
1216 This closes the dialog. Any unsaved changes will be
1218 </p></dd></dl></div><p>
1219 The rest of the dialog contains the parameters to be configured.
1220 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58627792"></a>6.1. Main Deploy Altitude</h3></div></div></div><p>
1221 This sets the altitude (above the recorded pad altitude) at
1222 which the 'main' igniter will fire. The drop-down menu shows
1223 some common values, but you can edit the text directly and
1224 choose whatever you like. If the apogee charge fires below
1225 this altitude, then the main charge will fire two seconds
1226 after the apogee charge fires.
1227 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58629360"></a>6.2. Apogee Delay</h3></div></div></div><p>
1228 When flying redundant electronics, it's often important to
1229 ensure that multiple apogee charges don't fire at precisely
1230 the same time, as that can over pressurize the apogee deployment
1231 bay and cause a structural failure of the air-frame. The Apogee
1232 Delay parameter tells the flight computer to fire the apogee
1233 charge a certain number of seconds after apogee has been
1235 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58630976"></a>6.3. Radio Frequency</h3></div></div></div><p>
1236 This configures which of the frequencies to use for both
1237 telemetry and packet command mode. Note that if you set this
1238 value via packet command mode, the TeleDongle frequency will
1239 also be automatically reconfigured to match so that
1240 communication will continue afterwards.
1241 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58632480"></a>6.4. RF Calibration</h3></div></div></div><p>
1242 The radios in every Altus Metrum device are calibrated at the
1243 factory to ensure that they transmit and receive on the
1244 specified frequency. If you need to you can adjust the calibration
1245 by changing this value. Do not do this without understanding what
1246 the value means, read the appendix on calibration and/or the source
1247 code for more information. To change a TeleDongle's calibration,
1248 you must reprogram the unit completely.
1249 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58634128"></a>6.5. Telemetry/RDF/APRS Enable</h3></div></div></div><p>
1250 Enables the radio for transmission during flight. When
1251 disabled, the radio will not transmit anything during flight
1253 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58635424"></a>6.6. APRS Interval</h3></div></div></div><p>
1254 How often to transmit GPS information via APRS. This option
1255 is available on TeleMetrum v2 and TeleMega
1256 boards. TeleMetrum v1 boards cannot transmit APRS
1257 packets. Note that a single APRS packet takes nearly a full
1258 second to transmit, so enabling this option will prevent
1259 sending any other telemetry during that time.
1260 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58636928"></a>6.7. Callsign</h3></div></div></div><p>
1261 This sets the call sign included in each telemetry packet. Set this
1262 as needed to conform to your local radio regulations.
1263 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58638240"></a>6.8. Maximum Flight Log Size</h3></div></div></div><p>
1264 This sets the space (in kilobytes) allocated for each flight
1265 log. The available space will be divided into chunks of this
1266 size. A smaller value will allow more flights to be stored,
1267 a larger value will record data from longer flights.
1268 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58639680"></a>6.9. Ignite Mode</h3></div></div></div><p>
1269 TeleMetrum and TeleMini provide two igniter channels as they
1270 were originally designed as dual-deploy flight
1271 computers. This configuration parameter allows the two
1272 channels to be used in different configurations.
1273 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Dual Deploy</span></dt><dd><p>
1274 This is the usual mode of operation; the
1275 'apogee' channel is fired at apogee and the 'main'
1276 channel at the height above ground specified by the
1277 'Main Deploy Altitude' during descent.
1278 </p></dd><dt><span class="term">Redundant Apogee</span></dt><dd><p>
1279 This fires both channels at
1280 apogee, the 'apogee' channel first followed after a two second
1281 delay by the 'main' channel.
1282 </p></dd><dt><span class="term">Redundant Main</span></dt><dd><p>
1283 This fires both channels at the
1284 height above ground specified by the Main Deploy
1285 Altitude setting during descent. The 'apogee'
1286 channel is fired first, followed after a two second
1287 delay by the 'main' channel.
1288 </p></dd></dl></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58646672"></a>6.10. Pad Orientation</h3></div></div></div><p>
1289 Because they include accelerometers, TeleMetrum and
1290 TeleMega are sensitive to the orientation of the board. By
1291 default, they expect the antenna end to point forward. This
1292 parameter allows that default to be changed, permitting the
1293 board to be mounted with the antenna pointing aft instead.
1294 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Antenna Up</span></dt><dd><p>
1295 In this mode, the antenna end of the
1296 flight computer must point forward, in line with the
1297 expected flight path.
1298 </p></dd><dt><span class="term">Antenna Down</span></dt><dd><p>
1299 In this mode, the antenna end of the
1300 flight computer must point aft, in line with the
1301 expected flight path.
1302 </p></dd></dl></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58651888"></a>6.11. Configure Pyro Channels</h3></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="540"><tr><td><img src="configure-pyro.png" width="540"></td></tr></table></div></div><p>
1303 This opens a separate window to configure the additional
1304 pyro channels available on TeleMega. One column is
1305 presented for each channel. Each row represents a single
1306 parameter, if enabled the parameter must meet the specified
1307 test for the pyro channel to be fired. See the Pyro Channels
1308 section in the System Operation chapter above for a
1309 description of these parameters.
1311 Select conditions and set the related value; the pyro
1312 channel will be activated when <span class="emphasis"><em>all</em></span> of the
1313 conditions are met. Each pyro channel has a separate set of
1314 configuration values, so you can use different values for
1315 the same condition with different channels.
1317 Once you have selected the appropriate configuration for all
1318 of the necessary pyro channels, you can save the pyro
1319 configuration along with the rest of the flight computer
1320 configuration by pressing the 'Save' button in the main
1321 Configure Flight Computer window.
1322 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58657696"></a>7. Configure AltosUI</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="225"><tr><td><img src="configure-altosui.png" width="225"></td></tr></table></div></div><p>
1323 This button presents a dialog so that you can configure the AltosUI global settings.
1324 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58661200"></a>7.1. Voice Settings</h3></div></div></div><p>
1325 AltosUI provides voice announcements during flight so that you
1326 can keep your eyes on the sky and still get information about
1327 the current flight status. However, sometimes you don't want
1329 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Enable</span></dt><dd><p>Turns all voice announcements on and off</p></dd><dt><span class="term">Test Voice</span></dt><dd><p>
1330 Plays a short message allowing you to verify
1331 that the audio system is working and the volume settings
1333 </p></dd></dl></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58666224"></a>7.2. Log Directory</h3></div></div></div><p>
1334 AltosUI logs all telemetry data and saves all TeleMetrum flash
1335 data to this directory. This directory is also used as the
1336 staring point when selecting data files for display or export.
1338 Click on the directory name to bring up a directory choosing
1339 dialog, select a new directory and click 'Select Directory' to
1340 change where AltosUI reads and writes data files.
1341 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58668224"></a>7.3. Callsign</h3></div></div></div><p>
1342 This value is transmitted in each command packet sent from
1343 TeleDongle and received from an altimeter. It is not used in
1344 telemetry mode, as the callsign configured in the altimeter board
1345 is included in all telemetry packets. Configure this
1346 with the AltosUI operators call sign as needed to comply with
1347 your local radio regulations.
1349 Note that to successfully command a flight computer over the radio
1350 (to configure the altimeter, monitor idle, or fire pyro charges),
1351 the callsign configured here must exactly match the callsign
1352 configured in the flight computer. This matching is case
1354 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58670464"></a>7.4. Imperial Units</h3></div></div></div><p>
1355 This switches between metric units (meters) and imperial
1356 units (feet and miles). This affects the display of values
1357 use during flight monitoring, configuration, data graphing
1358 and all of the voice announcements. It does not change the
1359 units used when exporting to CSV files, those are always
1360 produced in metric units.
1361 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58671968"></a>7.5. Font Size</h3></div></div></div><p>
1362 Selects the set of fonts used in the flight monitor
1363 window. Choose between the small, medium and large sets.
1364 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58673248"></a>7.6. Serial Debug</h3></div></div></div><p>
1365 This causes all communication with a connected device to be
1366 dumped to the console from which AltosUI was started. If
1367 you've started it from an icon or menu entry, the output
1368 will simply be discarded. This mode can be useful to debug
1369 various serial communication issues.
1370 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58674752"></a>7.7. Manage Frequencies</h3></div></div></div><p>
1371 This brings up a dialog where you can configure the set of
1372 frequencies shown in the various frequency menus. You can
1373 add as many as you like, or even reconfigure the default
1374 set. Changing this list does not affect the frequency
1375 settings of any devices, it only changes the set of
1376 frequencies shown in the menus.
1377 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58676384"></a>8. Configure Groundstation</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="270"><tr><td><img src="configure-groundstation.png" width="270"></td></tr></table></div></div><p>
1378 Select this button and then select a TeleDongle Device from the list provided.
1380 The first few lines of the dialog provide information about the
1381 connected device, including the product name,
1382 software version and hardware serial number. Below that are the
1383 individual configuration entries.
1385 Note that the TeleDongle itself doesn't save any configuration
1386 data, the settings here are recorded on the local machine in
1387 the Java preferences database. Moving the TeleDongle to
1388 another machine, or using a different user account on the same
1389 machine will cause settings made here to have no effect.
1391 At the bottom of the dialog, there are three buttons:
1392 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Save</span></dt><dd><p>
1393 This writes any changes to the
1394 local Java preferences file. If you don't
1395 press this button, any changes you make will be lost.
1396 </p></dd><dt><span class="term">Reset</span></dt><dd><p>
1397 This resets the dialog to the most recently saved values,
1398 erasing any changes you have made.
1399 </p></dd><dt><span class="term">Close</span></dt><dd><p>
1400 This closes the dialog. Any unsaved changes will be
1402 </p></dd></dl></div><p>
1403 The rest of the dialog contains the parameters to be configured.
1404 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58687504"></a>8.1. Frequency</h3></div></div></div><p>
1405 This configures the frequency to use for both telemetry and
1406 packet command mode. Set this before starting any operation
1407 involving packet command mode so that it will use the right
1408 frequency. Telemetry monitoring mode also provides a menu to
1409 change the frequency, and that menu also sets the same Java
1410 preference value used here.
1411 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58689072"></a>8.2. Radio Calibration</h3></div></div></div><p>
1412 The radios in every Altus Metrum device are calibrated at the
1413 factory to ensure that they transmit and receive on the
1414 specified frequency. To change a TeleDongle's calibration,
1415 you must reprogram the unit completely, so this entry simply
1416 shows the current value and doesn't allow any changes.
1417 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58690704"></a>9. Flash Image</h2></div></div></div><p>
1418 This reprograms Altus Metrum devices with new
1419 firmware. TeleMetrum v1.x, TeleDongle, TeleMini and TeleBT are
1420 all reprogrammed by using another similar unit as a
1421 programming dongle (pair programming). TeleMega, TeleMetrum v2
1422 and EasyMini are all programmed directly over their USB ports
1423 (self programming). Please read the directions for flashing
1424 devices in the Updating Device Firmware chapter below.
1425 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58692336"></a>10. Fire Igniter</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="90"><tr><td><img src="fire-igniter.png" width="90"></td></tr></table></div></div><p>
1426 This activates the igniter circuits in the flight computer to help
1427 test recovery systems deployment. Because this command can operate
1428 over the Packet Command Link, you can prepare the rocket as
1429 for flight and then test the recovery system without needing
1430 to snake wires inside the air-frame.
1432 Selecting the 'Fire Igniter' button brings up the usual device
1433 selection dialog. Pick the desired device. This brings up another
1434 window which shows the current continuity test status for both
1435 apogee and main charges.
1437 Next, select the desired igniter to fire. This will enable the
1440 Select the 'Arm' button. This enables the 'Fire' button. The
1441 word 'Arm' is replaced by a countdown timer indicating that
1442 you have 10 seconds to press the 'Fire' button or the system
1443 will deactivate, at which point you start over again at
1444 selecting the desired igniter.
1445 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58697968"></a>11. Scan Channels</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="248"><tr><td><img src="scan-channels.png" width="248"></td></tr></table></div></div><p>
1446 This listens for telemetry packets on all of the configured
1447 frequencies, displaying information about each device it
1448 receives a packet from. You can select which of the three
1449 telemetry formats should be tried; by default, it only listens
1450 for the standard telemetry packets used in v1.0 and later
1452 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58701824"></a>12. Load Maps</h2></div></div></div><div class="informalfigure"><div class="mediaobject"><table border="0" summary="manufactured viewport for HTML img" style="cellpadding: 0; cellspacing: 0;" width="495"><tr><td><img src="load-maps.png" width="495"></td></tr></table></div></div><p>
1453 Before heading out to a new launch site, you can use this to
1454 load satellite images in case you don't have internet
1455 connectivity at the site. This loads a fairly large area
1456 around the launch site, which should cover any flight you're likely to make.
1458 There's a drop-down menu of launch sites we know about; if
1459 your favorites aren't there, please let us know the lat/lon
1460 and name of the site. The contents of this list are actually
1461 downloaded from our server at run-time, so as new sites are sent
1462 in, they'll get automatically added to this list.
1464 If the launch site isn't in the list, you can manually enter the lat/lon values
1466 Clicking the 'Load Map' button will fetch images from Google
1467 Maps; note that Google limits how many images you can fetch at
1468 once, so if you load more than one launch site, you may get
1469 some gray areas in the map which indicate that Google is tired
1470 of sending data to you. Try again later.
1471 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58707520"></a>13. Monitor Idle</h2></div></div></div><p>
1472 This brings up a dialog similar to the Monitor Flight UI,
1473 except it works with the altimeter in “idle” mode by sending
1474 query commands to discover the current state rather than
1475 listening for telemetry packets. Because this uses command
1476 mode, it needs to have the TeleDongle and flight computer
1477 callsigns match exactly. If you can receive telemetry, but
1478 cannot manage to run Monitor Idle, then it's very likely that
1479 your callsigns are different in some way.
1480 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp58709616"></a>Chapter 7. AltosDroid</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp58712000">1. Installing AltosDroid</a></span></dt><dt><span class="section"><a href="#idp58713936">2. Connecting to TeleBT</a></span></dt><dt><span class="section"><a href="#idp58715936">3. Configuring AltosDroid</a></span></dt><dt><span class="section"><a href="#idp58717392">4. AltosDroid Flight Monitoring</a></span></dt><dd><dl><dt><span class="section"><a href="#idp58718704">4.1. Pad</a></span></dt></dl></dd><dt><span class="section"><a href="#idp58732256">5. Downloading Flight Logs</a></span></dt></dl></div><p>
1481 AltosDroid provides the same flight monitoring capabilities as
1482 AltosUI, but runs on Android devices and is designed to connect
1483 to a TeleBT receiver over Bluetooth™. AltosDroid monitors
1484 telemetry data, logging it to internal storage in the Android
1485 device, and presents that data in a UI the same way the 'Monitor
1486 Flight' window does in AltosUI.
1488 This manual will explain how to configure AltosDroid, connect
1489 to TeleBT, operate the flight monitoring interface and describe
1490 what the displayed data means.
1491 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58712000"></a>1. Installing AltosDroid</h2></div></div></div><p>
1492 AltosDroid is available from the Google Play store. To install
1493 it on your Android device, open the Google Play Store
1494 application and search for “altosdroid”. Make sure you don't
1495 have a space between “altos” and “droid” or you probably won't
1496 find what you want. That should bring you to the right page
1497 from which you can download and install the application.
1498 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58713936"></a>2. Connecting to TeleBT</h2></div></div></div><p>
1499 Press the Android 'Menu' button or soft-key to see the
1500 configuration options available. Select the 'Connect a device'
1501 option and then the 'Scan for devices' entry at the bottom to
1502 look for your TeleBT device. Select your device, and when it
1503 asks for the code, enter '1234'.
1505 Subsequent connections will not require you to enter that
1506 code, and your 'paired' device will appear in the list without
1508 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58715936"></a>3. Configuring AltosDroid</h2></div></div></div><p>
1509 The only configuration option available for AltosDroid is
1510 which frequency to listen on. Press the Android 'Menu' button
1511 or soft-key and pick the 'Select radio frequency' entry. That
1512 brings up a menu of pre-set radio frequencies; pick the one
1513 which matches your altimeter.
1514 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58717392"></a>4. AltosDroid Flight Monitoring</h2></div></div></div><p>
1515 AltosDroid is designed to mimic the AltosUI flight monitoring
1516 display, providing separate tabs for each stage of your rocket
1517 flight along with a tab containing a map of the local area
1518 with icons marking the current location of the altimeter and
1520 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58718704"></a>4.1. Pad</h3></div></div></div><p>
1521 The 'Launch Pad' tab shows information used to decide when the
1522 rocket is ready for flight. The first elements include red/green
1523 indicators, if any of these is red, you'll want to evaluate
1524 whether the rocket is ready to launch:
1525 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">Battery Voltage</span></dt><dd><p>
1526 This indicates whether the Li-Po battery
1527 powering the TeleMetrum has sufficient charge to last for
1528 the duration of the flight. A value of more than
1529 3.8V is required for a 'GO' status.
1530 </p></dd><dt><span class="term">Apogee Igniter Voltage</span></dt><dd><p>
1531 This indicates whether the apogee
1532 igniter has continuity. If the igniter has a low
1533 resistance, then the voltage measured here will be close
1534 to the Li-Po battery voltage. A value greater than 3.2V is
1535 required for a 'GO' status.
1536 </p></dd><dt><span class="term">Main Igniter Voltage</span></dt><dd><p>
1537 This indicates whether the main
1538 igniter has continuity. If the igniter has a low
1539 resistance, then the voltage measured here will be close
1540 to the Li-Po battery voltage. A value greater than 3.2V is
1541 required for a 'GO' status.
1542 </p></dd><dt><span class="term">On-board Data Logging</span></dt><dd><p>
1543 This indicates whether there is
1544 space remaining on-board to store flight data for the
1545 upcoming flight. If you've downloaded data, but failed
1546 to erase flights, there may not be any space
1547 left. TeleMetrum can store multiple flights, depending
1548 on the configured maximum flight log size. TeleMini
1549 stores only a single flight, so it will need to be
1550 downloaded and erased after each flight to capture
1551 data. This only affects on-board flight logging; the
1552 altimeter will still transmit telemetry and fire
1553 ejection charges at the proper times.
1554 </p></dd><dt><span class="term">GPS Locked</span></dt><dd><p>
1555 For a TeleMetrum or TeleMega device, this indicates whether the GPS receiver is
1556 currently able to compute position information. GPS requires
1557 at least 4 satellites to compute an accurate position.
1558 </p></dd><dt><span class="term">GPS Ready</span></dt><dd><p>
1559 For a TeleMetrum or TeleMega device, this indicates whether GPS has reported at least
1560 10 consecutive positions without losing lock. This ensures
1561 that the GPS receiver has reliable reception from the
1563 </p></dd></dl></div><p>
1565 The Launchpad tab also shows the computed launch pad position
1566 and altitude, averaging many reported positions to improve the
1567 accuracy of the fix.
1568 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58732256"></a>5. Downloading Flight Logs</h2></div></div></div><p>
1569 AltosDroid always saves every bit of telemetry data it
1570 receives. To download that to a computer for use with AltosUI,
1571 simply remove the SD card from your Android device, or connect
1572 your device to your computer's USB port and browse the files
1573 on that device. You will find '.telem' files in the TeleMetrum
1574 directory that will work with AltosUI directly.
1575 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp58733920"></a>Chapter 8. Using Altus Metrum Products</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp58734560">1. Being Legal</a></span></dt><dt><span class="section"><a href="#idp58736464">2. In the Rocket</a></span></dt><dt><span class="section"><a href="#idp58738928">3. On the Ground</a></span></dt><dt><span class="section"><a href="#idp58752240">4. Data Analysis</a></span></dt><dt><span class="section"><a href="#idp58754784">5. Future Plans</a></span></dt></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58734560"></a>1. Being Legal</h2></div></div></div><p>
1576 First off, in the US, you need an <a class="ulink" href="http://www.altusmetrum.org/Radio/" target="_top">amateur radio license</a> or
1577 other authorization to legally operate the radio transmitters that are part
1579 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58736464"></a>2. In the Rocket</h2></div></div></div><p>
1580 In the rocket itself, you just need a flight computer and
1581 a single-cell, 3.7 volt nominal Li-Po rechargeable battery. An
1582 850mAh battery weighs less than a 9V alkaline battery, and will
1583 run a TeleMetrum or TeleMega for hours.
1584 A 110mAh battery weighs less than a triple A battery and is a good
1585 choice for use with TeleMini.
1587 By default, we ship flight computers with a simple wire antenna.
1588 If your electronics bay or the air-frame it resides within is made
1589 of carbon fiber, which is opaque to RF signals, you may prefer to
1590 install an SMA connector so that you can run a coaxial cable to an
1591 antenna mounted elsewhere in the rocket. However, note that the
1592 GPS antenna is fixed on all current products, so you really want
1593 to install the flight computer in a bay made of RF-transparent
1594 materials if at all possible.
1595 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58738928"></a>3. On the Ground</h2></div></div></div><p>
1596 To receive the data stream from the rocket, you need an antenna and short
1597 feed-line connected to one of our <a class="ulink" href="http://www.altusmetrum.org/TeleDongle/" target="_top">TeleDongle</a> units. If possible, use an SMA to BNC
1598 adapter instead of feedline between the antenna feedpoint and
1599 TeleDongle, as this will give you the best performance. The
1600 TeleDongle in turn plugs directly into the USB port on a notebook
1601 computer. Because TeleDongle looks like a simple serial port, your computer
1602 does not require special device drivers... just plug it in.
1604 The GUI tool, AltosUI, is written in Java and runs across
1605 Linux, Mac OS and Windows. There's also a suite of C tools
1606 for Linux which can perform most of the same tasks.
1608 Alternatively, a TeleBT attached with an SMA to BNC adapter at the
1609 feed point of a hand-held yagi used in conjunction with an Android
1610 device running AltosDroid makes an outstanding ground station.
1612 After the flight, you can use the radio link to extract the more detailed data
1613 logged in either TeleMetrum or TeleMini devices, or you can use a mini USB cable to plug into the
1614 TeleMetrum board directly. Pulling out the data without having to open up
1615 the rocket is pretty cool! A USB cable is also how you charge the Li-Po
1616 battery, so you'll want one of those anyway... the same cable used by lots
1617 of digital cameras and other modern electronic stuff will work fine.
1619 If your rocket lands out of sight, you may enjoy having a hand-held
1620 GPS receiver, so that you can put in a way-point for the last
1621 reported rocket position before touch-down. This makes looking for
1622 your rocket a lot like Geo-Caching... just go to the way-point and
1623 look around starting from there. AltosDroid on an Android device
1624 with GPS receiver works great for this, too!
1626 You may also enjoy having a ham radio “HT” that covers the 70cm band... you
1627 can use that with your antenna to direction-find the rocket on the ground
1628 the same way you can use a Walston or Beeline tracker. This can be handy
1629 if the rocket is hiding in sage brush or a tree, or if the last GPS position
1630 doesn't get you close enough because the rocket dropped into a canyon, or
1631 the wind is blowing it across a dry lake bed, or something like that... Keith
1632 currently uses a Yaesu VX-7R, Bdale has a Baofung UV-5R
1633 which isn't as nice, but was a whole lot cheaper.
1635 So, to recap, on the ground the hardware you'll need includes:
1636 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
1637 an antenna and feed-line or adapter
1638 </p></li><li class="listitem"><p>
1640 </p></li><li class="listitem"><p>
1642 </p></li><li class="listitem"><p>
1643 optionally, a hand-held GPS receiver
1644 </p></li><li class="listitem"><p>
1645 optionally, an HT or receiver covering 435 MHz
1646 </p></li></ol></div><p>
1648 The best hand-held commercial directional antennas we've found for radio
1649 direction finding rockets are from
1650 <a class="ulink" href="http://www.arrowantennas.com/" target="_top">
1653 The 440-3 and 440-5 are both good choices for finding a
1654 TeleMetrum- or TeleMini- equipped rocket when used with a suitable
1655 70cm HT. TeleDongle and an SMA to BNC adapter fit perfectly
1656 between the driven element and reflector of Arrow antennas.
1657 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58752240"></a>4. Data Analysis</h2></div></div></div><p>
1658 Our software makes it easy to log the data from each flight, both the
1659 telemetry received during the flight itself, and the more
1660 complete data log recorded in the flash memory on the altimeter
1661 board. Once this data is on your computer, our post-flight tools make it
1662 easy to quickly get to the numbers everyone wants, like apogee altitude,
1663 max acceleration, and max velocity. You can also generate and view a
1664 standard set of plots showing the altitude, acceleration, and
1665 velocity of the rocket during flight. And you can even export a TeleMetrum data file
1666 usable with Google Maps and Google Earth for visualizing the flight path
1667 in two or three dimensions!
1669 Our ultimate goal is to emit a set of files for each flight that can be
1670 published as a web page per flight, or just viewed on your local disk with
1672 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58754784"></a>5. Future Plans</h2></div></div></div><p>
1673 We've designed a simple GPS based radio tracker called TeleGPS.
1674 If all goes well, we hope to introduce this in the first
1677 We have designed and prototyped several “companion boards” that
1678 can attach to the companion connector on TeleMetrum and TeleMega
1679 flight computers to collect more data, provide more pyro channels,
1680 and so forth. We do not yet know if or when any of these boards
1681 will be produced in enough quantity to sell. If you have specific
1682 interests for data collection or control of events in your rockets
1683 beyond the capabilities of our existing productions, please let
1686 Because all of our work is open, both the hardware designs and the
1687 software, if you have some great idea for an addition to the current
1688 Altus Metrum family, feel free to dive in and help! Or let us know
1689 what you'd like to see that we aren't already working on, and maybe
1690 we'll get excited about it too...
1693 <a class="ulink" href="http://altusmetrum.org/" target="_top">web site</a> for more news
1694 and information as our family of products evolves!
1695 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp58759168"></a>Chapter 9. Altimeter Installation Recommendations</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp58760624">1. Mounting the Altimeter</a></span></dt><dt><span class="section"><a href="#idp58766032">2. Dealing with the Antenna</a></span></dt><dt><span class="section"><a href="#idp58771600">3. Preserving GPS Reception</a></span></dt><dt><span class="section"><a href="#idp58776384">4. Radio Frequency Interference</a></span></dt><dt><span class="section"><a href="#idp58783952">5. The Barometric Sensor</a></span></dt><dt><span class="section"><a href="#idp58786752">6. Ground Testing</a></span></dt></dl></div><p>
1696 Building high-power rockets that fly safely is hard enough. Mix
1697 in some sophisticated electronics and a bunch of radio energy
1698 and some creativity and/or compromise may be required. This chapter
1699 contains some suggestions about how to install Altus Metrum
1700 products into a rocket air-frame, including how to safely and
1701 reliably mix a variety of electronics into the same air-frame.
1702 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58760624"></a>1. Mounting the Altimeter</h2></div></div></div><p>
1703 The first consideration is to ensure that the altimeter is
1704 securely fastened to the air-frame. For most of our products, we
1705 prefer nylon standoffs and nylon screws; they're good to at least 50G
1706 and cannot cause any electrical issues on the board. Metal screws
1707 and standoffs are fine, too, just be careful to avoid electrical
1708 shorts! For TeleMini v1.0, we usually cut small pieces of 1/16 inch
1710 under the screw holes, and then take 2x56 nylon screws and
1711 screw them through the TeleMini mounting holes, through the
1712 balsa and into the underlying material.
1713 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
1714 Make sure accelerometer-equipped products like TeleMetrum and
1715 TeleMega are aligned precisely along the axis of
1716 acceleration so that the accelerometer can accurately
1717 capture data during the flight.
1718 </p></li><li class="listitem"><p>
1719 Watch for any metal touching components on the
1720 board. Shorting out connections on the bottom of the board
1721 can cause the altimeter to fail during flight.
1722 </p></li></ol></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58766032"></a>2. Dealing with the Antenna</h2></div></div></div><p>
1723 The antenna supplied is just a piece of solid, insulated,
1724 wire. If it gets damaged or broken, it can be easily
1725 replaced. It should be kept straight and not cut; bending or
1726 cutting it will change the resonant frequency and/or
1727 impedance, making it a less efficient radiator and thus
1728 reducing the range of the telemetry signal.
1730 Keeping metal away from the antenna will provide better range
1731 and a more even radiation pattern. In most rockets, it's not
1732 entirely possible to isolate the antenna from metal
1733 components; there are often bolts, all-thread and wires from other
1734 electronics to contend with. Just be aware that the more stuff
1735 like this around the antenna, the lower the range.
1737 Make sure the antenna is not inside a tube made or covered
1738 with conducting material. Carbon fiber is the most common
1739 culprit here -- CF is a good conductor and will effectively
1740 shield the antenna, dramatically reducing signal strength and
1741 range. Metallic flake paint is another effective shielding
1742 material which should be avoided around any antennas.
1744 If the ebay is large enough, it can be convenient to simply
1745 mount the altimeter at one end and stretch the antenna out
1746 inside. Taping the antenna to the sled can keep it straight
1747 under acceleration. If there are metal rods, keep the
1748 antenna as far away as possible.
1750 For a shorter ebay, it's quite practical to have the antenna
1751 run through a bulkhead and into an adjacent bay. Drill a small
1752 hole in the bulkhead, pass the antenna wire through it and
1753 then seal it up with glue or clay. We've also used acrylic
1754 tubing to create a cavity for the antenna wire. This works a
1755 bit better in that the antenna is known to stay straight and
1756 not get folded by recovery components in the bay. Angle the
1757 tubing towards the side wall of the rocket and it ends up
1758 consuming very little space.
1760 If you need to place the UHF antenna at a distance from the
1761 altimeter, you can replace the antenna with an edge-mounted
1762 SMA connector, and then run 50Ω coax from the board to the
1763 antenna. Building a remote antenna is beyond the scope of this
1765 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58771600"></a>3. Preserving GPS Reception</h2></div></div></div><p>
1766 The GPS antenna and receiver used in TeleMetrum and TeleMega is
1767 highly sensitive and normally have no trouble tracking enough
1768 satellites to provide accurate position information for
1769 recovering the rocket. However, there are many ways the GPS signal
1770 can end up attenuated, negatively affecting GPS performance.
1771 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
1772 Conductive tubing or coatings. Carbon fiber and metal
1773 tubing, or metallic paint will all dramatically attenuate the
1774 GPS signal. We've never heard of anyone successfully
1775 receiving GPS from inside these materials.
1776 </p></li><li class="listitem"><p>
1777 Metal components near the GPS patch antenna. These will
1778 de-tune the patch antenna, changing the resonant frequency
1779 away from the L1 carrier and reduce the effectiveness of the
1780 antenna. You can place as much stuff as you like beneath the
1781 antenna as that's covered with a ground plane. But, keep
1782 wires and metal out from above the patch antenna.
1783 </p></li></ol></div><p>
1784 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58776384"></a>4. Radio Frequency Interference</h2></div></div></div><p>
1785 Any altimeter will generate RFI; the digital circuits use
1786 high-frequency clocks that spray radio interference across a
1787 wide band. Altus Metrum altimeters generate intentional radio
1788 signals as well, increasing the amount of RF energy around the board.
1790 Rocketry altimeters also use precise sensors measuring air
1791 pressure and acceleration. Tiny changes in voltage can cause
1792 these sensor readings to vary by a huge amount. When the
1793 sensors start mis-reporting data, the altimeter can either
1794 fire the igniters at the wrong time, or not fire them at all.
1796 Voltages are induced when radio frequency energy is
1797 transmitted from one circuit to another. Here are things that
1798 influence the induced voltage and current:
1799 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
1800 Keep wires from different circuits apart. Moving circuits
1801 further apart will reduce RFI.
1802 </p></li><li class="listitem"><p>
1803 Avoid parallel wires from different circuits. The longer two
1804 wires run parallel to one another, the larger the amount of
1805 transferred energy. Cross wires at right angles to reduce
1807 </p></li><li class="listitem"><p>
1808 Twist wires from the same circuits. Two wires the same
1809 distance from the transmitter will get the same amount of
1810 induced energy which will then cancel out. Any time you have
1811 a wire pair running together, twist the pair together to
1812 even out distances and reduce RFI. For altimeters, this
1813 includes battery leads, switch hookups and igniter
1815 </p></li><li class="listitem"><p>
1816 Avoid resonant lengths. Know what frequencies are present
1817 in the environment and avoid having wire lengths near a
1818 natural resonant length. Altus Metrum products transmit on the
1819 70cm amateur band, so you should avoid lengths that are a
1820 simple ratio of that length; essentially any multiple of ¼
1821 of the wavelength (17.5cm).
1822 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58783952"></a>5. The Barometric Sensor</h2></div></div></div><p>
1823 Altusmetrum altimeters measure altitude with a barometric
1824 sensor, essentially measuring the amount of air above the
1825 rocket to figure out how high it is. A large number of
1826 measurements are taken as the altimeter initializes itself to
1827 figure out the pad altitude. Subsequent measurements are then
1828 used to compute the height above the pad.
1830 To accurately measure atmospheric pressure, the ebay
1831 containing the altimeter must be vented outside the
1832 air-frame. The vent must be placed in a region of linear
1833 airflow, have smooth edges, and away from areas of increasing or
1834 decreasing pressure.
1836 All barometric sensors are quite sensitive to chemical damage from
1837 the products of APCP or BP combustion, so make sure the ebay is
1838 carefully sealed from any compartment which contains ejection
1840 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58786752"></a>6. Ground Testing</h2></div></div></div><p>
1841 The most important aspect of any installation is careful
1842 ground testing. Bringing an air-frame up to the LCO table which
1843 hasn't been ground tested can lead to delays or ejection
1844 charges firing on the pad, or, even worse, a recovery system
1847 Do a 'full systems' test that includes wiring up all igniters
1848 without any BP and turning on all of the electronics in flight
1849 mode. This will catch any mistakes in wiring and any residual
1850 RFI issues that might accidentally fire igniters at the wrong
1851 time. Let the air-frame sit for several minutes, checking for
1852 adequate telemetry signal strength and GPS lock. If any igniters
1853 fire unexpectedly, find and resolve the issue before loading any
1856 Ground test the ejection charges. Prepare the rocket for
1857 flight, loading ejection charges and igniters. Completely
1858 assemble the air-frame and then use the 'Fire Igniters'
1859 interface through a TeleDongle to command each charge to
1860 fire. Make sure the charge is sufficient to robustly separate
1861 the air-frame and deploy the recovery system.
1862 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp58789920"></a>Chapter 10. Updating Device Firmware</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp58793936">1.
1863 Updating TeleMega, TeleMetrum v2 or EasyMini Firmware
1864 </a></span></dt><dd><dl><dt><span class="section"><a href="#idp58802752">1.1. Recovering From Self-Flashing Failure</a></span></dt></dl></dd><dt><span class="section"><a href="#idp58811728">2. Pair Programming</a></span></dt><dt><span class="section"><a href="#idp58813168">3. Updating TeleMetrum v1.x Firmware</a></span></dt><dt><span class="section"><a href="#idp58826208">4. Updating TeleMini Firmware</a></span></dt><dt><span class="section"><a href="#idp58839600">5. Updating TeleDongle Firmware</a></span></dt></dl></div><p>
1865 TeleMega, TeleMetrum v2 and EasyMini are all programmed directly
1866 over their USB connectors (self programming). TeleMetrum v1, TeleMini and
1867 TeleDongle are all programmed by using another device as a
1868 programmer (pair programming). It's important to recognize which
1869 kind of devices you have before trying to reprogram them.
1871 You may wish to begin by ensuring you have current firmware images.
1872 These are distributed as part of the AltOS software bundle that
1873 also includes the AltosUI ground station program. Newer ground
1874 station versions typically work fine with older firmware versions,
1875 so you don't need to update your devices just to try out new
1876 software features. You can always download the most recent
1877 version from <a class="ulink" href="http://www.altusmetrum.org/AltOS/" target="_top">http://www.altusmetrum.org/AltOS/</a>.
1879 If you need to update the firmware on a TeleDongle, we recommend
1880 updating the altimeter first, before updating TeleDongle. However,
1881 note that TeleDongle rarely need to be updated. Any firmware version
1882 1.0.1 or later will work, version 1.2.1 may have improved receiver
1883 performance slightly.
1885 Self-programmable devices (TeleMega, TeleMetrum v2 and EasyMini)
1886 are reprogrammed by connecting them to your computer over USB
1887 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58793936"></a>1.
1888 Updating TeleMega, TeleMetrum v2 or EasyMini Firmware
1889 </h2></div></div></div><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
1890 Attach a battery and power switch to the target
1891 device. Power up the device.
1892 </p></li><li class="listitem"><p>
1893 Using a Micro USB cable, connect the target device to your
1894 computer's USB socket.
1895 </p></li><li class="listitem"><p>
1896 Run AltosUI, and select 'Flash Image' from the File menu.
1897 </p></li><li class="listitem"><p>
1898 Select the target device in the Device Selection dialog.
1899 </p></li><li class="listitem"><p>
1900 Select the image you want to flash to the device, which
1901 should have a name in the form
1902 <product>-v<product-version>-<software-version>.ihx, such
1903 as TeleMega-v1.0-1.3.0.ihx.
1904 </p></li><li class="listitem"><p>
1905 Make sure the configuration parameters are reasonable
1906 looking. If the serial number and/or RF configuration
1907 values aren't right, you'll need to change them.
1908 </p></li><li class="listitem"><p>
1909 Hit the 'OK' button and the software should proceed to flash
1910 the device with new firmware, showing a progress bar.
1911 </p></li><li class="listitem"><p>
1912 Verify that the device is working by using the 'Configure
1913 Altimeter' item to check over the configuration.
1914 </p></li></ol></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp58802752"></a>1.1. Recovering From Self-Flashing Failure</h3></div></div></div><p>
1915 If the firmware loading fails, it can leave the device
1916 unable to boot. Not to worry, you can force the device to
1917 start the boot loader instead, which will let you try to
1918 flash the device again.
1920 On each device, connecting two pins from one of the exposed
1921 connectors will force the boot loader to start, even if the
1922 regular operating system has been corrupted in some way.
1923 </p><div class="variablelist"><dl class="variablelist"><dt><span class="term">TeleMega</span></dt><dd><p>
1924 Connect pin 6 and pin 1 of the companion connector. Pin 1
1925 can be identified by the square pad around it, and then
1926 the pins could sequentially across the board. Be very
1927 careful to <span class="emphasis"><em>not</em></span> short pin 8 to
1928 anything as that is connected directly to the battery. Pin
1929 7 carries 3.3V and the board will crash if that is
1930 connected to pin 1, but shouldn't damage the board.
1931 </p></dd><dt><span class="term">TeleMetrum v2</span></dt><dd><p>
1932 Connect pin 6 and pin 1 of the companion connector. Pin 1
1933 can be identified by the square pad around it, and then
1934 the pins could sequentially across the board. Be very
1935 careful to <span class="emphasis"><em>not</em></span> short pin 8 to
1936 anything as that is connected directly to the battery. Pin
1937 7 carries 3.3V and the board will crash if that is
1938 connected to pin 1, but shouldn't damage the board.
1939 </p></dd><dt><span class="term">EasyMini</span></dt><dd><p>
1940 Connect pin 6 and pin 1 of the debug connector, which is
1941 the six holes next to the beeper. Pin 1 can be identified
1942 by the square pad around it, and then the pins could
1943 sequentially across the board, making Pin 6 the one on the
1944 other end of the row.
1945 </p></dd></dl></div></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58811728"></a>2. Pair Programming</h2></div></div></div><p>
1946 The big concept to understand is that you have to use a
1947 TeleMega, TeleMetrum or TeleDongle as a programmer to update a
1948 pair programmed device. Due to limited memory resources in the
1949 cc1111, we don't support programming directly over USB for these
1951 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58813168"></a>3. Updating TeleMetrum v1.x Firmware</h2></div></div></div><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
1952 Find the 'programming cable' that you got as part of the starter
1953 kit, that has a red 8-pin MicroMaTch connector on one end and a
1954 red 4-pin MicroMaTch connector on the other end.
1955 </p></li><li class="listitem"><p>
1956 Take the 2 screws out of the TeleDongle case to get access
1957 to the circuit board.
1958 </p></li><li class="listitem"><p>
1959 Plug the 8-pin end of the programming cable to the
1960 matching connector on the TeleDongle, and the 4-pin end to the
1961 matching connector on the TeleMetrum.
1962 Note that each MicroMaTch connector has an alignment pin that
1963 goes through a hole in the PC board when you have the cable
1965 </p></li><li class="listitem"><p>
1966 Attach a battery to the TeleMetrum board.
1967 </p></li><li class="listitem"><p>
1968 Plug the TeleDongle into your computer's USB port, and power
1970 </p></li><li class="listitem"><p>
1971 Run AltosUI, and select 'Flash Image' from the File menu.
1972 </p></li><li class="listitem"><p>
1973 Pick the TeleDongle device from the list, identifying it as the
1975 </p></li><li class="listitem"><p>
1976 Select the image you want put on the TeleMetrum, which should have a
1977 name in the form telemetrum-v1.2-1.0.0.ihx. It should be visible
1978 in the default directory, if not you may have to poke around
1979 your system to find it.
1980 </p></li><li class="listitem"><p>
1981 Make sure the configuration parameters are reasonable
1982 looking. If the serial number and/or RF configuration
1983 values aren't right, you'll need to change them.
1984 </p></li><li class="listitem"><p>
1985 Hit the 'OK' button and the software should proceed to flash
1986 the TeleMetrum with new firmware, showing a progress bar.
1987 </p></li><li class="listitem"><p>
1988 Confirm that the TeleMetrum board seems to have updated OK, which you
1989 can do by plugging in to it over USB and using a terminal program
1990 to connect to the board and issue the 'v' command to check
1992 </p></li><li class="listitem"><p>
1993 If something goes wrong, give it another try.
1994 </p></li></ol></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58826208"></a>4. Updating TeleMini Firmware</h2></div></div></div><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
1995 You'll need a special 'programming cable' to reprogram the
1996 TeleMini. You can make your own using an 8-pin MicroMaTch
1997 connector on one end and a set of four pins on the other.
1998 </p></li><li class="listitem"><p>
1999 Take the 2 screws out of the TeleDongle case to get access
2000 to the circuit board.
2001 </p></li><li class="listitem"><p>
2002 Plug the 8-pin end of the programming cable to the matching
2003 connector on the TeleDongle, and the 4-pins into the holes
2004 in the TeleMini circuit board. Note that the MicroMaTch
2005 connector has an alignment pin that goes through a hole in
2006 the PC board when you have the cable oriented correctly, and
2007 that pin 1 on the TeleMini board is marked with a square pad
2008 while the other pins have round pads.
2009 </p></li><li class="listitem"><p>
2010 Attach a battery to the TeleMini board.
2011 </p></li><li class="listitem"><p>
2012 Plug the TeleDongle into your computer's USB port, and power
2014 </p></li><li class="listitem"><p>
2015 Run AltosUI, and select 'Flash Image' from the File menu.
2016 </p></li><li class="listitem"><p>
2017 Pick the TeleDongle device from the list, identifying it as the
2019 </p></li><li class="listitem"><p>
2020 Select the image you want put on the TeleMini, which should have a
2021 name in the form telemini-v1.0-1.0.0.ihx. It should be visible
2022 in the default directory, if not you may have to poke around
2023 your system to find it.
2024 </p></li><li class="listitem"><p>
2025 Make sure the configuration parameters are reasonable
2026 looking. If the serial number and/or RF configuration
2027 values aren't right, you'll need to change them.
2028 </p></li><li class="listitem"><p>
2029 Hit the 'OK' button and the software should proceed to flash
2030 the TeleMini with new firmware, showing a progress bar.
2031 </p></li><li class="listitem"><p>
2032 Confirm that the TeleMini board seems to have updated OK, which you
2033 can do by configuring it over the radio link through the TeleDongle, or
2034 letting it come up in “flight” mode and listening for telemetry.
2035 </p></li><li class="listitem"><p>
2036 If something goes wrong, give it another try.
2037 </p></li></ol></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58839600"></a>5. Updating TeleDongle Firmware</h2></div></div></div><p>
2038 Updating TeleDongle's firmware is just like updating TeleMetrum or TeleMini
2039 firmware, but you use either a TeleMetrum or another TeleDongle as the programmer.
2040 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>
2041 Find the 'programming cable' that you got as part of the starter
2042 kit, that has a red 8-pin MicroMaTch connector on one end and a
2043 red 4-pin MicroMaTch connector on the other end.
2044 </p></li><li class="listitem"><p>
2045 Find the USB cable that you got as part of the starter kit, and
2046 plug the “mini” end in to the mating connector on TeleMetrum or TeleDongle.
2047 </p></li><li class="listitem"><p>
2048 Take the 2 screws out of the TeleDongle case to get access
2049 to the circuit board.
2050 </p></li><li class="listitem"><p>
2051 Plug the 8-pin end of the programming cable to the
2052 matching connector on the programmer, and the 4-pin end to the
2053 matching connector on the TeleDongle.
2054 Note that each MicroMaTch connector has an alignment pin that
2055 goes through a hole in the PC board when you have the cable
2057 </p></li><li class="listitem"><p>
2058 Attach a battery to the TeleMetrum board if you're using one.
2059 </p></li><li class="listitem"><p>
2060 Plug both the programmer and the TeleDongle into your computer's USB
2061 ports, and power up the programmer.
2062 </p></li><li class="listitem"><p>
2063 Run AltosUI, and select 'Flash Image' from the File menu.
2064 </p></li><li class="listitem"><p>
2065 Pick the programmer device from the list, identifying it as the
2067 </p></li><li class="listitem"><p>
2068 Select the image you want put on the TeleDongle, which should have a
2069 name in the form teledongle-v0.2-1.0.0.ihx. It should be visible
2070 in the default directory, if not you may have to poke around
2071 your system to find it.
2072 </p></li><li class="listitem"><p>
2073 Make sure the configuration parameters are reasonable
2074 looking. If the serial number and/or RF configuration
2075 values aren't right, you'll need to change them. The TeleDongle
2076 serial number is on the “bottom” of the circuit board, and can
2077 usually be read through the translucent blue plastic case without
2078 needing to remove the board from the case.
2079 </p></li><li class="listitem"><p>
2080 Hit the 'OK' button and the software should proceed to flash
2081 the TeleDongle with new firmware, showing a progress bar.
2082 </p></li><li class="listitem"><p>
2083 Confirm that the TeleDongle board seems to have updated OK, which you
2084 can do by plugging in to it over USB and using a terminal program
2085 to connect to the board and issue the 'v' command to check
2086 the version, etc. Once you're happy, remove the programming cable
2087 and put the cover back on the TeleDongle.
2088 </p></li><li class="listitem"><p>
2089 If something goes wrong, give it another try.
2090 </p></li></ol></div><p>
2091 Be careful removing the programming cable from the locking 8-pin
2092 connector on TeleMetrum. You'll need a fingernail or perhaps a thin
2093 screwdriver or knife blade to gently pry the locking ears out
2094 slightly to extract the connector. We used a locking connector on
2095 TeleMetrum to help ensure that the cabling to companion boards
2096 used in a rocket don't ever come loose accidentally in flight.
2097 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp58856144"></a>Chapter 11. Hardware Specifications</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp58856784">1.
2098 TeleMega Specifications
2099 </a></span></dt><dt><span class="section"><a href="#idp58868016">2.
2100 TeleMetrum v2 Specifications
2101 </a></span></dt><dt><span class="section"><a href="#idp58878256">3. TeleMetrum v1 Specifications</a></span></dt><dt><span class="section"><a href="#idp58888496">4.
2102 TeleMini v2.0 Specifications
2103 </a></span></dt><dt><span class="section"><a href="#idp58897328">5.
2104 TeleMini v1.0 Specifications
2105 </a></span></dt><dt><span class="section"><a href="#idp58906128">6.
2106 EasyMini Specifications
2107 </a></span></dt></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58856784"></a>1.
2108 TeleMega Specifications
2109 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2110 Recording altimeter for model rocketry.
2111 </p></li><li class="listitem"><p>
2112 Supports dual deployment and four auxiliary pyro channels
2113 (a total of 6 events).
2114 </p></li><li class="listitem"><p>
2115 70cm 40mW ham-band transceiver for telemetry down-link.
2116 </p></li><li class="listitem"><p>
2117 Barometric pressure sensor good to 100k feet MSL.
2118 </p></li><li class="listitem"><p>
2119 1-axis high-g accelerometer for motor characterization, capable of
2121 </p></li><li class="listitem"><p>
2122 9-axis IMU including integrated 3-axis accelerometer,
2123 3-axis gyroscope and 3-axis magnetometer.
2124 </p></li><li class="listitem"><p>
2125 On-board, integrated uBlox Max 7 GPS receiver with 5Hz update rate capability.
2126 </p></li><li class="listitem"><p>
2127 On-board 8 Megabyte non-volatile memory for flight data storage.
2128 </p></li><li class="listitem"><p>
2129 USB interface for battery charging, configuration, and data recovery.
2130 </p></li><li class="listitem"><p>
2131 Fully integrated support for Li-Po rechargeable batteries.
2132 </p></li><li class="listitem"><p>
2133 Can use either main system Li-Po or optional separate pyro battery
2135 </p></li><li class="listitem"><p>
2136 3.25 x 1.25 inch board designed to fit inside 38mm air-frame coupler tube.
2137 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58868016"></a>2.
2138 TeleMetrum v2 Specifications
2139 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2140 Recording altimeter for model rocketry.
2141 </p></li><li class="listitem"><p>
2142 Supports dual deployment (can fire 2 ejection charges).
2143 </p></li><li class="listitem"><p>
2144 70cm, 40mW ham-band transceiver for telemetry down-link.
2145 </p></li><li class="listitem"><p>
2146 Barometric pressure sensor good to 100k feet MSL.
2147 </p></li><li class="listitem"><p>
2148 1-axis high-g accelerometer for motor characterization, capable of
2150 </p></li><li class="listitem"><p>
2151 On-board, integrated uBlox Max 7 GPS receiver with 5Hz update rate capability.
2152 </p></li><li class="listitem"><p>
2153 On-board 8 Megabyte non-volatile memory for flight data storage.
2154 </p></li><li class="listitem"><p>
2155 USB interface for battery charging, configuration, and data recovery.
2156 </p></li><li class="listitem"><p>
2157 Fully integrated support for Li-Po rechargeable batteries.
2158 </p></li><li class="listitem"><p>
2159 Uses Li-Po to fire e-matches, can be modified to support
2160 optional separate pyro battery if needed.
2161 </p></li><li class="listitem"><p>
2162 2.75 x 1 inch board designed to fit inside 29mm air-frame coupler tube.
2163 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58878256"></a>3. TeleMetrum v1 Specifications</h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2164 Recording altimeter for model rocketry.
2165 </p></li><li class="listitem"><p>
2166 Supports dual deployment (can fire 2 ejection charges).
2167 </p></li><li class="listitem"><p>
2168 70cm, 10mW ham-band transceiver for telemetry down-link.
2169 </p></li><li class="listitem"><p>
2170 Barometric pressure sensor good to 45k feet MSL.
2171 </p></li><li class="listitem"><p>
2172 1-axis high-g accelerometer for motor characterization, capable of
2173 +/- 50g using default part.
2174 </p></li><li class="listitem"><p>
2175 On-board, integrated GPS receiver with 5Hz update rate capability.
2176 </p></li><li class="listitem"><p>
2177 On-board 1 megabyte non-volatile memory for flight data storage.
2178 </p></li><li class="listitem"><p>
2179 USB interface for battery charging, configuration, and data recovery.
2180 </p></li><li class="listitem"><p>
2181 Fully integrated support for Li-Po rechargeable batteries.
2182 </p></li><li class="listitem"><p>
2183 Uses Li-Po to fire e-matches, can be modified to support
2184 optional separate pyro battery if needed.
2185 </p></li><li class="listitem"><p>
2186 2.75 x 1 inch board designed to fit inside 29mm air-frame coupler tube.
2187 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58888496"></a>4.
2188 TeleMini v2.0 Specifications
2189 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2190 Recording altimeter for model rocketry.
2191 </p></li><li class="listitem"><p>
2192 Supports dual deployment (can fire 2 ejection charges).
2193 </p></li><li class="listitem"><p>
2194 70cm, 10mW ham-band transceiver for telemetry down-link.
2195 </p></li><li class="listitem"><p>
2196 Barometric pressure sensor good to 100k feet MSL.
2197 </p></li><li class="listitem"><p>
2198 On-board 1 megabyte non-volatile memory for flight data storage.
2199 </p></li><li class="listitem"><p>
2200 USB interface for configuration, and data recovery.
2201 </p></li><li class="listitem"><p>
2202 Support for Li-Po rechargeable batteries (using an
2203 external charger), or any 3.7-15V external battery.
2204 </p></li><li class="listitem"><p>
2205 Uses Li-Po to fire e-matches, can be modified to support
2206 optional separate pyro battery if needed.
2207 </p></li><li class="listitem"><p>
2208 1.5 x .8 inch board designed to fit inside 24mm air-frame coupler tube.
2209 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58897328"></a>5.
2210 TeleMini v1.0 Specifications
2211 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2212 Recording altimeter for model rocketry.
2213 </p></li><li class="listitem"><p>
2214 Supports dual deployment (can fire 2 ejection charges).
2215 </p></li><li class="listitem"><p>
2216 70cm, 10mW ham-band transceiver for telemetry down-link.
2217 </p></li><li class="listitem"><p>
2218 Barometric pressure sensor good to 45k feet MSL.
2219 </p></li><li class="listitem"><p>
2220 On-board 5 kilobyte non-volatile memory for flight data storage.
2221 </p></li><li class="listitem"><p>
2222 RF interface for configuration, and data recovery.
2223 </p></li><li class="listitem"><p>
2224 Support for Li-Po rechargeable batteries, using an external charger.
2225 </p></li><li class="listitem"><p>
2226 Uses Li-Po to fire e-matches, can be modified to support
2227 optional separate pyro battery if needed.
2228 </p></li><li class="listitem"><p>
2229 1.5 x .5 inch board designed to fit inside 18mm air-frame coupler tube.
2230 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58906128"></a>6.
2231 EasyMini Specifications
2232 </h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2233 Recording altimeter for model rocketry.
2234 </p></li><li class="listitem"><p>
2235 Supports dual deployment (can fire 2 ejection charges).
2236 </p></li><li class="listitem"><p>
2237 Barometric pressure sensor good to 100k feet MSL.
2238 </p></li><li class="listitem"><p>
2239 On-board 1 megabyte non-volatile memory for flight data storage.
2240 </p></li><li class="listitem"><p>
2241 USB interface for configuration, and data recovery.
2242 </p></li><li class="listitem"><p>
2243 Support for Li-Po rechargeable batteries (using an
2244 external charger), or any 3.7-15V external battery.
2245 </p></li><li class="listitem"><p>
2246 Uses Li-Po to fire e-matches, can be modified to support
2247 optional separate pyro battery if needed.
2248 </p></li><li class="listitem"><p>
2249 1.5 x .8 inch board designed to fit inside 24mm air-frame coupler tube.
2250 </p></li></ul></div></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp58914240"></a>Chapter 12. FAQ</h1></div></div></div><p>
2251 <span class="emphasis"><em>TeleMetrum seems to shut off when disconnected from the
2252 computer.</em></span>
2253 Make sure the battery is adequately charged. Remember the
2254 unit will pull more power than the USB port can deliver before the
2255 GPS enters “locked” mode. The battery charges best when TeleMetrum
2258 <span class="emphasis"><em>It's impossible to stop the TeleDongle when it's in “p” mode, I have
2259 to unplug the USB cable? </em></span>
2260 Make sure you have tried to “escape out” of
2261 this mode. If this doesn't work the reboot procedure for the
2262 TeleDongle *is* to simply unplug it. 'cu' however will retain it's
2263 outgoing buffer IF your “escape out” ('~~') does not work.
2264 At this point using either 'ao-view' (or possibly
2265 'cutemon') instead of 'cu' will 'clear' the issue and allow renewed
2268 <span class="emphasis"><em>The amber LED (on the TeleMetrum) lights up when both
2269 battery and USB are connected. Does this mean it's charging?
2271 Yes, the yellow LED indicates the charging at the 'regular' rate.
2272 If the led is out but the unit is still plugged into a USB port,
2273 then the battery is being charged at a 'trickle' rate.
2275 <span class="emphasis"><em>There are no “dit-dah-dah-dit” sound or lights like the manual
2276 mentions?</em></span>
2277 That's the “pad” mode. Weak batteries might be the problem.
2278 It is also possible that the flight computer is horizontal and the
2280 is instead a “dit-dit” meaning 'idle'. For TeleMini, it's possible that
2281 it received a command packet which would have left it in “pad” mode.
2283 <span class="emphasis"><em>How do I save flight data?</em></span>
2284 Live telemetry is written to file(s) whenever AltosUI is connected
2285 to the TeleDongle. The file area defaults to ~/TeleMetrum
2286 but is easily changed using the menus in AltosUI. The files that
2287 are written end in '.telem'. The after-flight
2288 data-dumped files will end in .eeprom and represent continuous data
2289 unlike the .telem files that are subject to losses
2290 along the RF data path.
2291 See the above instructions on what and how to save the eeprom stored
2292 data after physically retrieving your altimeter. Make sure to save
2293 the on-board data after each flight; while the TeleMetrum can store
2294 multiple flights, you never know when you'll lose the altimeter...
2295 </p></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a name="idp58923088"></a>Appendix A. Notes for Older Software</h1></div></div></div><p>
2296 <span class="emphasis"><em>
2297 Before AltosUI was written, using Altus Metrum devices required
2298 some finesse with the Linux command line. There was a limited
2299 GUI tool, ao-view, which provided functionality similar to the
2300 Monitor Flight window in AltosUI, but everything else was a
2301 fairly 80's experience. This appendix includes documentation for
2302 using that software.
2305 Both TeleMetrum and TeleDongle can be directly communicated
2306 with using USB ports. The first thing you should try after getting
2307 both units plugged into to your computer's USB port(s) is to run
2308 'ao-list' from a terminal-window to see what port-device-name each
2309 device has been assigned by the operating system.
2310 You will need this information to access the devices via their
2311 respective on-board firmware and data using other command line
2312 programs in the AltOS software suite.
2314 TeleMini can be communicated with through a TeleDongle device
2315 over the radio link. When first booted, TeleMini listens for a
2316 TeleDongle device and if it receives a packet, it goes into
2317 'idle' mode. Otherwise, it goes into 'pad' mode and waits to be
2318 launched. The easiest way to get it talking is to start the
2319 communication link on the TeleDongle and the power up the
2322 To access the device's firmware for configuration you need a terminal
2323 program such as you would use to talk to a modem. The software
2324 authors prefer using the program 'cu' which comes from the UUCP package
2325 on most Unix-like systems such as Linux. An example command line for
2326 cu might be 'cu -l /dev/ttyACM0', substituting the correct number
2327 indicated from running the
2328 ao-list program. Another reasonable terminal program for Linux is
2329 'cutecom'. The default 'escape'
2330 character used by CU (i.e. the character you use to
2331 issue commands to cu itself instead of sending the command as input
2332 to the connected device) is a '~'. You will need this for use in
2333 only two different ways during normal operations. First is to exit
2334 the program by sending a '~.' which is called a 'escape-disconnect'
2335 and allows you to close-out from 'cu'. The
2336 second use will be outlined later.
2338 All of the Altus Metrum devices share the concept of a two level
2339 command set in their firmware.
2340 The first layer has several single letter commands. Once
2341 you are using 'cu' (or 'cutecom') sending (typing) a '?'
2342 returns a full list of these
2343 commands. The second level are configuration sub-commands accessed
2344 using the 'c' command, for
2345 instance typing 'c?' will give you this second level of commands
2346 (all of which require the
2347 letter 'c' to access). Please note that most configuration options
2348 are stored only in Flash memory; TeleDongle doesn't provide any storage
2349 for these options and so they'll all be lost when you unplug it.
2351 Try setting these configuration ('c' or second level menu) values. A good
2352 place to start is by setting your call sign. By default, the boards
2353 use 'N0CALL' which is cute, but not exactly legal!
2354 Spend a few minutes getting comfortable with the units, their
2355 firmware, and 'cu' (or possibly 'cutecom').
2356 For instance, try to send
2357 (type) a 'c r 2' and verify the channel change by sending a 'c s'.
2358 Verify you can connect and disconnect from the units while in your
2359 terminal program by sending the escape-disconnect mentioned above.
2361 To set the radio frequency, use the 'c R' command to specify the
2362 radio transceiver configuration parameter. This parameter is computed
2363 using the desired frequency, 'F', the radio calibration parameter, 'C' (showed by the 'c s' command) and
2364 the standard calibration reference frequency, 'S', (normally 434.550MHz):
2365 </p><pre class="programlisting">
2368 Round the result to the nearest integer value.
2369 As with all 'c' sub-commands, follow this with a 'c w' to write the
2370 change to the parameter block in the on-board flash on
2371 your altimeter board if you want the change to stay in place across reboots.
2373 To set the apogee delay, use the 'c d' command.
2374 As with all 'c' sub-commands, follow this with a 'c w' to write the
2375 change to the parameter block in the on-board DataFlash chip.
2377 To set the main deployment altitude, use the 'c m' command.
2378 As with all 'c' sub-commands, follow this with a 'c w' to write the
2379 change to the parameter block in the on-board DataFlash chip.
2381 To calibrate the radio frequency, connect the UHF antenna port to a
2382 frequency counter, set the board to 434.550MHz, and use the 'C'
2383 command to generate a CW carrier. Wait for the transmitter temperature
2384 to stabilize and the frequency to settle down.
2385 Then, divide 434.550 MHz by the
2386 measured frequency and multiply by the current radio cal value show
2387 in the 'c s' command. For an unprogrammed board, the default value
2388 is 1186611. Take the resulting integer and program it using the 'c f'
2389 command. Testing with the 'C' command again should show a carrier
2390 within a few tens of Hertz of the intended frequency.
2391 As with all 'c' sub-commands, follow this with a 'c w' to write the
2392 change to the parameter block in the on-board DataFlash chip.
2394 Note that the 'reboot' command, which is very useful on the altimeters,
2395 will likely just cause problems with the dongle. The *correct* way
2396 to reset the dongle is just to unplug and re-plug it.
2398 A fun thing to do at the launch site and something you can do while
2399 learning how to use these units is to play with the radio link access
2400 between an altimeter and the TeleDongle. Be aware that you *must* create
2401 some physical separation between the devices, otherwise the link will
2402 not function due to signal overload in the receivers in each device.
2404 Now might be a good time to take a break and read the rest of this
2405 manual, particularly about the two “modes” that the altimeters
2406 can be placed in. TeleMetrum uses the position of the device when booting
2407 up will determine whether the unit is in “pad” or “idle” mode. TeleMini
2408 enters “idle” mode when it receives a command packet within the first 5 seconds
2409 of being powered up, otherwise it enters “pad” mode.
2411 You can access an altimeter in idle mode from the TeleDongle's USB
2412 connection using the radio link
2413 by issuing a 'p' command to the TeleDongle. Practice connecting and
2414 disconnecting ('~~' while using 'cu') from the altimeter. If
2415 you cannot escape out of the “p” command, (by using a '~~' when in
2416 CU) then it is likely that your kernel has issues. Try a newer version.
2418 Using this radio link allows you to configure the altimeter, test
2419 fire e-matches and igniters from the flight line, check pyro-match
2420 continuity and so forth. You can leave the unit turned on while it
2421 is in 'idle mode' and then place the
2422 rocket vertically on the launch pad, walk away and then issue a
2423 reboot command. The altimeter will reboot and start sending data
2424 having changed to the “pad” mode. If the TeleDongle is not receiving
2425 this data, you can disconnect 'cu' from the TeleDongle using the
2426 procedures mentioned above and THEN connect to the TeleDongle from
2427 inside 'ao-view'. If this doesn't work, disconnect from the
2428 TeleDongle, unplug it, and try again after plugging it back in.
2430 In order to reduce the chance of accidental firing of pyrotechnic
2431 charges, the command to fire a charge is intentionally somewhat
2432 difficult to type, and the built-in help is slightly cryptic to
2433 prevent accidental echoing of characters from the help text back at
2434 the board from firing a charge. The command to fire the apogee
2435 drogue charge is 'i DoIt drogue' and the command to fire the main
2436 charge is 'i DoIt main'.
2438 On TeleMetrum, the GPS will eventually find enough satellites, lock in on them,
2439 and 'ao-view' will both auditorily announce and visually indicate
2441 Now you can launch knowing that you have a good data path and
2442 good satellite lock for flight data and recovery. Remember
2443 you MUST tell ao-view to connect to the TeleDongle explicitly in
2444 order for ao-view to be able to receive data.
2446 The altimeters provide RDF (radio direction finding) tones on
2447 the pad, during descent and after landing. These can be used to
2448 locate the rocket using a directional antenna; the signal
2449 strength providing an indication of the direction from receiver to rocket.
2451 TeleMetrum also provides GPS tracking data, which can further simplify
2452 locating the rocket once it has landed. (The last good GPS data
2453 received before touch-down will be on the data screen of 'ao-view'.)
2455 Once you have recovered the rocket you can download the eeprom
2456 contents using either 'ao-dumplog' (or possibly 'ao-eeprom'), over
2457 either a USB cable or over the radio link using TeleDongle.
2458 And by following the man page for 'ao-postflight' you can create
2459 various data output reports, graphs, and even KML data to see the
2460 flight trajectory in Google-earth. (Moving the viewing angle making
2461 sure to connect the yellow lines while in Google-earth is the proper
2464 As for ao-view.... some things are in the menu but don't do anything
2465 very useful. The developers have stopped working on ao-view to focus
2466 on a new, cross-platform ground station program. So ao-view may or
2467 may not be updated in the future. Mostly you just use
2468 the Log and Device menus. It has a wonderful display of the incoming
2469 flight data and I am sure you will enjoy what it has to say to you
2470 once you enable the voice output!
2471 </p></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a name="idp58946464"></a>Appendix B. Drill Templates</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp58947632">1. TeleMega template</a></span></dt><dt><span class="section"><a href="#idp58963600">2. TeleMetrum template</a></span></dt><dt><span class="section"><a href="#idp58967264">3. TeleMini v2/EasyMini template</a></span></dt><dt><span class="section"><a href="#idp58970944">4. TeleMini v1 template</a></span></dt></dl></div><p>
2472 These images, when printed, provide precise templates for the
2473 mounting holes in Altus Metrum flight computers
2474 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58947632"></a>1. TeleMega template</h2></div></div></div><p>
2475 TeleMega has overall dimensions of 1.250 x 3.250 inches, and
2476 the mounting holes are sized for use with 4-40 or M3 screws.
2477 </p><div class="informalfigure"><div class="mediaobject"><a name="TeleMegaTemplate"></a><object type="image/svg+xml" data="telemega-outline.svg"></object></div></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58963600"></a>2. TeleMetrum template</h2></div></div></div><p>
2478 TeleMetrum has overall dimensions of 1.000 x 2.750 inches, and the
2479 mounting holes are sized for use with 4-40 or M3 screws.
2480 </p><div class="informalfigure"><div class="mediaobject"><a name="TeleMetrumTemplate"></a><object type="image/svg+xml" data="telemetrum.svg"></object></div></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58967264"></a>3. TeleMini v2/EasyMini template</h2></div></div></div><p>
2481 TeleMini v2 and EasyMini have overall dimensions of 0.800 x 1.500 inches, and the
2482 mounting holes are sized for use with 4-40 or M3 screws.
2483 </p><div class="informalfigure"><div class="mediaobject"><a name="MiniTemplate"></a><object type="image/svg+xml" data="easymini-outline.svg"></object></div></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58970944"></a>4. TeleMini v1 template</h2></div></div></div><p>
2484 TeleMini has overall dimensions of 0.500 x 1.500 inches, and the
2485 mounting holes are sized for use with 2-56 or M2 screws.
2486 </p><div class="informalfigure"><div class="mediaobject"><a name="TeleMiniTemplate"></a><object type="image/svg+xml" data="telemini.svg"></object></div></div></div></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a name="idp58974736"></a>Appendix C. Calibration</h1></div></div></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp58976288">1. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp58980832">2. TeleMetrum and TeleMega Accelerometers</a></span></dt></dl></div><p>
2487 There are only two calibrations required for TeleMetrum and
2488 TeleMega, and only one for TeleDongle, TeleMini and EasyMini.
2489 All boards are shipped from the factory pre-calibrated, but
2490 the procedures are documented here in case they are ever
2491 needed. Re-calibration is not supported by AltosUI, you must
2492 connect to the board with a serial terminal program and
2493 interact directly with the on-board command interpreter to
2495 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58976288"></a>1. Radio Frequency</h2></div></div></div><p>
2496 The radio frequency is synthesized from a clock based on the
2497 crystal on the board. The actual frequency of this oscillator
2498 must be measured to generate a calibration constant. While our
2500 bandwidth is wide enough to allow boards to communicate even when
2501 their oscillators are not on exactly the same frequency, performance
2502 is best when they are closely matched.
2503 Radio frequency calibration requires a calibrated frequency counter.
2504 Fortunately, once set, the variation in frequency due to aging and
2505 temperature changes is small enough that re-calibration by customers
2506 should generally not be required.
2508 To calibrate the radio frequency, connect the UHF antenna
2509 port to a frequency counter, set the board to 434.550MHz,
2510 and use the 'C' command in the on-board command interpreter
2511 to generate a CW carrier. For USB-enabled boards, this is
2512 best done over USB. For TeleMini v1, note that the only way
2513 to escape the 'C' command is via power cycle since the board
2514 will no longer be listening for commands once it starts
2515 generating a CW carrier.
2517 Wait for the transmitter temperature to stabilize and the frequency
2518 to settle down. Then, divide 434.550 MHz by the
2519 measured frequency and multiply by the current radio cal value show
2520 in the 'c s' command. For an unprogrammed board, the default value
2521 is 1186611. Take the resulting integer and program it using the 'c f'
2522 command. Testing with the 'C' command again should show a carrier
2523 within a few tens of Hertz of the intended frequency.
2524 As with all 'c' sub-commands, follow this with a 'c w' to write the
2525 change to the parameter block in the on-board storage chip.
2527 Note that any time you re-do the radio frequency calibration, the
2528 radio frequency is reset to the default 434.550 Mhz. If you want
2529 to use another frequency, you will have to set that again after
2530 calibration is completed.
2531 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58980832"></a>2. TeleMetrum and TeleMega Accelerometers</h2></div></div></div><p>
2532 While barometric sensors are factory-calibrated,
2533 accelerometers are not, and so each must be calibrated once
2534 installed in a flight computer. Explicitly calibrating the
2535 accelerometers also allows us to load any compatible device.
2536 We perform a two-point calibration using gravity.
2538 To calibrate the acceleration sensor, use the 'c a 0' command. You
2539 will be prompted to orient the board vertically with the UHF antenna
2540 up and press a key, then to orient the board vertically with the
2541 UHF antenna down and press a key. Note that the accuracy of this
2542 calibration depends primarily on how perfectly vertical and still
2543 the board is held during the cal process. As with all 'c'
2544 sub-commands, follow this with a 'c w' to write the
2545 change to the parameter block in the on-board DataFlash chip.
2547 The +1g and -1g calibration points are included in each telemetry
2548 frame and are part of the header stored in onboard flash to be
2549 downloaded after flight. We always store and return raw ADC
2550 samples for each sensor... so nothing is permanently “lost” or
2551 “damaged” if the calibration is poor.
2553 In the unlikely event an accel cal goes badly, it is possible
2554 that TeleMetrum or TeleMega may always come up in 'pad mode'
2555 and as such not be listening to either the USB or radio link.
2556 If that happens, there is a special hook in the firmware to
2557 force the board back in to 'idle mode' so you can re-do the
2558 cal. To use this hook, you just need to ground the SPI clock
2559 pin at power-on. This pin is available as pin 2 on the 8-pin
2560 companion connector, and pin 1 is ground. So either
2561 carefully install a fine-gauge wire jumper between the two
2562 pins closest to the index hole end of the 8-pin connector, or
2563 plug in the programming cable to the 8-pin connector and use
2564 a small screwdriver or similar to short the two pins closest
2565 to the index post on the 4-pin end of the programming cable,
2566 and power up the board. It should come up in 'idle mode'
2567 (two beeps), allowing a re-cal.
2568 </p></div></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a name="idp58985936"></a>Appendix D. Release Notes</h1></div></div></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58986576"></a>Version 1.3</h2></div></div></div><p>
2569 Version 1.3 is a major release. It adds support for TeleMega,
2570 TeleMetrum v2.0, TeleMini v2.0 and EasyMini.
2572 AltOS Firmware Changes
2573 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2574 Add STM32L processor support. This includes enhancements to
2575 the scheduler to support products with many threads.
2576 </p></li><li class="listitem"><p>
2577 Add NXP LPC11U14 processor support.
2578 </p></li><li class="listitem"><p>
2579 Support additional pyro channels. These are configurable
2580 through the UI to handle air starts, staging, additional
2581 recovery events and external devices such as cameras.
2582 </p></li><li class="listitem"><p>
2583 Add 3-axis gyro support for orientation tracking. This
2584 integrates the gyros to compute the angle from vertical during
2585 flight, allowing the additional pyro events to be controlled
2587 </p></li><li class="listitem"><p>
2588 Many more device drivers, including u-Blox Max 7Q GPS,
2589 Freescale MMA6555 digital single-axis accelerometer,
2590 Invensense MPU6000 3-axis accelerometer + 3 axis gyro,
2591 Honeywell HMC5883 3-axis magnetic sensor and the TI CC1120 and
2592 CC115L digital FM transceivers
2593 </p></li></ul></div><p>
2596 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2597 Support TeleMega, TeleMetrum v2.0, TeleMini v2.0 and EasyMini telemetry and log formats.
2598 </p></li><li class="listitem"><p>
2599 Use preferred units for main deployment height configuration,
2600 instead of always doing configuration in meters.
2601 </p></li></ul></div><p>
2603 MicroPeak UI changes
2604 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2605 Add 'Download' button to menu bar.
2606 </p></li><li class="listitem"><p>
2607 Save the last log directory and offer that as the default for new downloads
2608 </p></li></ul></div><p>
2609 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58988176"></a>Version 1.2.1</h2></div></div></div><p>
2610 Version 1.2.1 is a minor release. It adds support for TeleBT and
2611 the AltosDroid application, provides several new features in
2612 AltosUI and fixes some bugs in the AltOS firmware.
2614 AltOS Firmware Changes
2615 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2616 Add support for TeleBT
2617 </p></li><li class="listitem"><p>
2618 In TeleMini recovery mode (when booted with the outer two
2619 debug pins connected together), the radio parameters are also
2620 set back to defaults (434.550MHz, N0CALL, factory radio cal).
2621 </p></li><li class="listitem"><p>
2622 Add support for reflashing the SkyTraq GPS chips. This
2623 requires special host-side code which currently only exists
2625 </p></li><li class="listitem"><p>
2626 Correct Kalman filter model error covariance matrix. The
2627 values used previously assumed continuous measurements instead
2628 of discrete measurements.
2629 </p></li><li class="listitem"><p>
2630 Fix some bugs in the USB driver for TeleMetrum and TeleDongle
2631 that affected Windows users.
2632 </p></li><li class="listitem"><p>
2633 Adjusted the automatic gain control parameters that affect
2634 receive performance for TeleDongle. Field tests indicate that this
2635 may improve receive performance somewhat.
2636 </p></li></ul></div><p>
2639 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2640 Handle missing GPS lock in 'Descent' tab. Previously, if the
2641 GPS position of the pad was unknown, an exception would be
2642 raised, breaking the Descent tab contents.
2643 </p></li><li class="listitem"><p>
2644 Improve the graph, adding tool-tips to show values near the
2645 cursor and making the displayed set of values configurable,
2646 adding all of the flight data as options while leaving the
2647 default settings alone so that the graph starts by showing
2648 height, speed and acceleration.
2649 </p></li><li class="listitem"><p>
2650 Make the initial position of the AltosUI top level window
2651 configurable. Along with this change, the other windows will
2652 pop up at 'sensible' places now, instead of on top of one
2654 </p></li><li class="listitem"><p>
2655 Add callsign to Monitor idle window and connecting
2656 dialogs. This makes it clear which callsign is being used so
2657 that the operator will be aware that it must match the flight
2658 computer value or no communication will work.
2659 </p></li><li class="listitem"><p>
2660 When downloading flight data, display the block number so that
2661 the user has some sense of progress. Unfortunately, we don't
2662 know how many blocks will need to be downloaded, but at least
2663 it isn't just sitting there doing nothing for a long time.
2664 </p></li><li class="listitem"><p>
2665 Add GPS data and a map to the graph window. This lets you see
2666 a complete summary of the flight without needing to 'replay'
2668 </p></li></ul></div><p>
2669 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58989776"></a>Version 1.2</h2></div></div></div><p>
2670 Version 1.2 is a major release. It adds support for MicroPeak and
2671 the MicroPeak USB adapter.
2673 AltOS Firmware Changes
2674 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2675 Add MicroPeak support. This includes support for the ATtiny85
2676 processor and adaptations to the core code to allow for
2677 devices too small to run the multi-tasking scheduler.
2678 </p></li></ul></div><p>
2680 MicroPeak UI changes
2681 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2682 Added this new application
2683 </p></li></ul></div><p>
2685 Distribution Changes
2686 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2687 Distribute Mac OS X packages in disk image ('.dmg') format to
2688 greatly simplify installation.
2689 </p></li><li class="listitem"><p>
2690 Provide version numbers for the shared Java libraries to
2691 ensure that upgrades work properly, and to allow for multiple
2692 Altus Metrum software packages to be installed in the same
2693 directory at the same time.
2694 </p></li></ul></div><p>
2695 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58991280"></a>Version 1.1.1</h2></div></div></div><p>
2696 Version 1.1.1 is a bug-fix release. It fixes a couple of bugs in
2697 AltosUI and one firmware bug that affects TeleMetrum version 1.0
2698 boards. Thanks to Bob Brown for help diagnosing the Google Earth
2699 file export issue, and for suggesting the addition of the Ground
2700 Distance value in the Descent tab.
2702 AltOS Firmware Changes
2703 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2704 TeleMetrum v1.0 boards use the AT45DB081D flash memory part to
2705 store flight data, which is different from later TeleMetrum
2706 boards. The AltOS v1.1 driver for this chip couldn't erase
2707 memory, leaving it impossible to delete flight data or update
2708 configuration values. This bug doesn't affect newer TeleMetrum
2709 boards, and it doesn't affect the safety of rockets flying
2710 version 1.1 firmware.
2711 </p></li></ul></div><p>
2714 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2715 Creating a Google Earth file (KML) from on-board flight data
2716 (EEPROM) would generate an empty file. The code responsible
2717 for reading the EEPROM file wasn't ever setting the GPS valid
2718 bits, and so the KML export code thought there was no GPS data
2720 </p></li><li class="listitem"><p>
2721 The “Landed” tab was displaying all values in metric units,
2722 even when AltosUI was configured to display imperial
2723 units. Somehow I just missed this tab when doing the units stuff.
2724 </p></li><li class="listitem"><p>
2725 The “Descent” tab displays the range to the rocket, which is a
2726 combination of the over-the-ground distance to the rockets
2727 current latitude/longitude and the height of the rocket. As
2728 such, it's useful for knowing how far away the rocket is, but
2729 difficult to use when estimating where the rocket might
2730 eventually land. A new “Ground Distance” field has been added
2731 which displays the distance to a spot right underneath the
2733 </p></li><li class="listitem"><p>
2734 Sensor data wasn't being displayed for TeleMini flight
2735 computers in Monitor Idle mode, including things like battery
2736 voltage. The code that picked which kinds of data to fetch
2737 from the flight computer was missing a check for TeleMini when
2738 deciding whether to fetch the analog sensor data.
2739 </p></li></ul></div><p>
2740 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58992784"></a>Version 1.1</h2></div></div></div><p>
2741 Version 1.1 is a minor release. It provides a few new features in AltosUI
2742 and the AltOS firmware and fixes bugs.
2744 AltOS Firmware Changes
2745 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2746 Add apogee-lockout value. Overrides the apogee detection logic to
2747 prevent incorrect apogee charge firing.
2748 </p></li><li class="listitem"><p>
2749 Fix a bug where the data reported in telemetry packets was
2751 </p></li><li class="listitem"><p>
2752 Force the radio frequency to 434.550MHz when the debug clock
2753 pin is connected to ground at boot time. This provides a way
2754 to talk to a TeleMini which is configured to some unknown frequency.
2755 </p></li><li class="listitem"><p>
2756 Provide RSSI values for Monitor Idle mode. This makes it easy to check radio
2757 range without needing to go to flight mode.
2758 </p></li><li class="listitem"><p>
2759 Fix a bug which caused the old received telemetry packets to
2760 be retransmitted over the USB link when the radio was turned
2762 </p></li></ul></div><p>
2765 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2766 Fix a bug that caused GPS ready to happen too quickly. The
2767 software was using every telemetry packet to signal new GPS
2768 data, which caused GPS ready to be signalled after 10 packets
2769 instead of 10 GPS updates.
2770 </p></li><li class="listitem"><p>
2771 Fix Google Earth data export to work with recent versions. The
2772 google earth file loading code got a lot pickier, requiring
2773 some minor white space changes in the export code.
2774 </p></li><li class="listitem"><p>
2775 Make the look-n-feel configurable, providing a choice from
2776 the available options.
2777 </p></li><li class="listitem"><p>
2778 Add an 'Age' element to mark how long since a telemetry packet
2779 has been received. Useful to quickly gauge whether
2780 communications with the rocket are still active.
2781 </p></li><li class="listitem"><p>
2782 Add 'Configure Ground Station' dialog to set the radio
2783 frequency used by a particular TeleDongle without having to go
2784 through the flight monitor UI.
2785 </p></li><li class="listitem"><p>
2786 Add configuration for the new apogee-lockout value. A menu provides a list of
2787 reasonable values, or the value can be set by hand.
2788 </p></li><li class="listitem"><p>
2789 Changed how flight data are downloaded. Now there's an initial
2790 dialog asking which flights to download, and after that
2791 finishes, a second dialog comes up asking which flights to delete.
2792 </p></li><li class="listitem"><p>
2793 Re-compute time spent in each state for the flight graph; this
2794 figures out the actual boost and landing times instead of
2795 using the conservative values provide by the flight
2796 electronics. This improves the accuracy of the boost
2797 acceleration and main descent rate computations.
2798 </p></li><li class="listitem"><p>
2799 Make AltosUI run on Mac OS Lion. The default Java heap space
2800 was dramatically reduced for this release causing much of the
2801 UI to fail randomly. This most often affected the satellite
2802 mapping download and displays.
2803 </p></li><li class="listitem"><p>
2804 Change how data are displayed in the 'table' tab of the flight
2805 monitoring window. This eliminates entries duplicated from the
2806 header and adds both current altitude and pad altitude, which
2807 are useful in 'Monitor Idle' mode.
2808 </p></li><li class="listitem"><p>
2809 Add Imperial units mode to present data in feet instead of
2811 </p></li></ul></div><p>
2812 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58994288"></a>Version 1.0.1</h2></div></div></div><p>
2813 Version 1.0.1 is a major release, adding support for the TeleMini
2814 device and lots of new AltosUI features
2816 AltOS Firmware Changes
2817 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2818 Add TeleMini v1.0 support. Firmware images for TeleMini are
2819 included in AltOS releases.
2820 </p></li><li class="listitem"><p>
2821 Change telemetry to be encoded in multiple 32-byte packets. This
2822 enables support for TeleMini and other devices without requiring
2823 further updates to the TeleDongle firmware.
2824 </p></li><li class="listitem"><p>
2825 Support operation of TeleMetrum with the antenna pointing
2826 aft. Previous firmware versions required the antenna to be
2827 pointing upwards, now there is a configuration option allowing
2828 the antenna to point aft, to aid installation in some airframes.
2829 </p></li><li class="listitem"><p>
2830 Ability to disable telemetry. For airframes where an antenna
2831 just isn't possible, or where radio transmissions might cause
2832 trouble with other electronics, there's a configuration option
2833 to disable all telemetry. Note that the board will still
2834 enable the radio link in idle mode.
2835 </p></li><li class="listitem"><p>
2836 Arbitrary frequency selection. The radios in Altus Metrum
2837 devices can be programmed to a wide range of frequencies, so
2838 instead of limiting devices to 10 pre-selected 'channels', the
2839 new firmware allows the user to choose any frequency in the
2840 70cm band. Note that the RF matching circuit on the boards is
2841 tuned for around 435MHz, so frequencies far from that may
2842 reduce the available range.
2843 </p></li><li class="listitem"><p>
2844 Kalman-filter based flight-tracking. The model based sensor
2845 fusion approach of a Kalman filter means that AltOS now
2846 computes apogee much more accurately than before, generally
2847 within a fraction of a second. In addition, this approach
2848 allows the baro-only TeleMini device to correctly identify
2849 Mach transitions, avoiding the error-prone selection of a Mach
2851 </p></li></ul></div><p>
2854 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2855 Wait for altimeter when using packet mode. Instead of quicly
2856 timing out when trying to initialize a packet mode
2857 configuration connection, AltosUI now waits indefinitely for
2858 the remote device to appear, providing a cancel button should
2859 the user get bored. This is necessary as the TeleMini can only
2860 be placed in "Idle" mode if AltosUI is polling it.
2861 </p></li><li class="listitem"><p>
2862 Add main/apogee voltage graphs to the data plot. This provides
2863 a visual indication if the igniters fail before being fired.
2864 </p></li><li class="listitem"><p>
2865 Scan for altimeter devices by watching the defined telemetry
2866 frequencies. This avoids the problem of remembering what
2867 frequency a device was configured to use, which is especially
2868 important with TeleMini which does not include a USB connection.
2869 </p></li><li class="listitem"><p>
2870 Monitor altimeter state in "Idle" mode. This provides much of
2871 the information presented in the "Pad" dialog from the Monitor
2872 Flight command, monitoring the igniters, battery and GPS
2873 status withing requiring the flight computer to be armed and
2875 </p></li><li class="listitem"><p>
2876 Pre-load map images from home. For those launch sites which
2877 don't provide free Wi-Fi, this allows you to download the
2878 necessary satellite images given the location of the launch
2879 site. A list of known launch sites is maintained at
2880 altusmetrum.org which AltosUI downloads to populate a menu; if
2881 you've got a launch site not on that list, please send the
2882 name of it, latitude and longitude along with a link to the
2883 web site of the controlling club to the altusmetrum mailing list.
2884 </p></li><li class="listitem"><p>
2885 Flight statistics are now displayed in the Graph data
2886 window. These include max height/speed/accel, average descent
2887 rates and a few other bits of information. The Graph Data
2888 window can now be reached from the 'Landed' tab in the Monitor
2889 Flight window so you can immediately see the results of a
2891 </p></li></ul></div><p>
2892 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58995792"></a>Version 0.9.2</h2></div></div></div><p>
2893 Version 0.9.2 is an AltosUI bug-fix release, with no firmware changes.
2894 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2895 Fix plotting problems due to missing file in the Mac OS install image.
2896 </p></li><li class="listitem"><p>
2897 Always read whole eeprom blocks, mark empty records invalid, display parsing errors to user.
2898 </p></li><li class="listitem"><p>
2899 Add software version to Configure AltosUI dialog
2900 </p></li></ul></div></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58997296"></a>Version 0.9</h2></div></div></div><p>
2901 Version 0.9 adds a few new firmware features and accompanying
2902 AltosUI changes, along with new hardware support.
2903 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2904 Support for TeleMetrum v1.1 hardware. Sources for the flash
2905 memory part used in v1.0 dried up, so v1.1 uses a different part
2906 which required a new driver and support for explicit flight log
2908 </p></li><li class="listitem"><p>
2909 Multiple flight log support. This stores more than one flight
2910 log in the on-board flash memory. It also requires the user to
2911 explicitly erase flights so that you won't lose flight logs just
2912 because you fly the same board twice in one day.
2913 </p></li><li class="listitem"><p>
2914 Telemetry support for devices with serial number >=
2915 256. Previous versions used a telemetry packet format that
2916 provided only 8 bits for the device serial number. This change
2917 requires that both ends of the telemetry link be running the 0.9
2918 firmware or they will not communicate.
2919 </p></li></ul></div></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp58998800"></a>Version 0.8</h2></div></div></div><p>
2920 Version 0.8 offers a major upgrade in the AltosUI
2921 interface. Significant new features include:
2922 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2923 Post-flight graphing tool. This lets you explore the behaviour
2924 of your rocket after flight with a scroll-able and zoom-able
2925 chart showing the altitude, speed and acceleration of the
2926 airframe along with events recorded by the flight computer. You
2927 can export graphs to PNG files, or print them directly.
2928 </p></li><li class="listitem"><p>
2929 Real-time moving map which overlays the in-progress flight on
2930 satellite imagery fetched from Google Maps. This lets you see in
2931 pictures where your rocket has landed, allowing you to plan
2932 recovery activities more accurately.
2933 </p></li><li class="listitem"><p>
2934 Wireless recovery system testing. Prep your rocket for flight
2935 and test fire the deployment charges to make sure things work as
2936 expected. All without threading wires through holes in your
2938 </p></li><li class="listitem"><p>
2939 Optimized flight status displays. Each flight state now has it's
2940 own custom 'tab' in the flight monitoring window so you can
2941 focus on the most important details. Pre-flight, the system
2942 shows a set of red/green status indicators for battery voltage,
2943 apogee/main igniter continutity and GPS reception. Wait until
2944 they're all green and your rocket is ready for flight. There are
2945 also tabs for ascent, descent and landing along with the
2946 original tabular view of the data.
2947 </p></li><li class="listitem"><p>
2948 Monitor multiple flights simultaneously. If you have more than
2949 one TeleDongle, you can monitor a flight with each one on the
2951 </p></li><li class="listitem"><p>
2952 Automatic flight monitoring at startup. Plug TeleDongle into the
2953 machine before starting AltosUI and it will automatically
2954 connect to it and prepare to monitor a flight.
2955 </p></li><li class="listitem"><p>
2956 Exports Google Earth flight tracks. Using the Keyhole Markup
2957 Language (.kml) file format, this provides a 3D view of your
2958 rocket flight through the Google Earth program.
2959 </p></li></ul></div></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp59000304"></a>Version 0.7.1</h2></div></div></div><p>
2960 Version 0.7.1 is the first release containing our new cross-platform Java-based user interface. AltosUI can:
2961 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
2962 Receive and log telemetry from a connected TeleDongle
2963 device. All data received is saved to log files named with the
2964 current date and the connected rocket serial and flight
2965 numbers. There is no mode in which telemetry data will not be
2967 </p></li><li class="listitem"><p>
2968 Download logged data from TeleMetrum devices, either through a
2969 direct USB connection or over the air through a TeleDongle
2971 </p></li><li class="listitem"><p>
2972 Configure a TeleMetrum device, setting the radio channel,
2973 callsign, apogee delay and main deploy height. This can be done
2974 through either a USB connection or over a radio link via a
2976 </p></li><li class="listitem"><p>
2977 Replay a flight in real-time. This takes a saved telemetry log
2978 or eeprom download and replays it through the user interface so
2979 you can relive your favorite rocket flights.
2980 </p></li><li class="listitem"><p>
2981 Reprogram Altus Metrum devices. Using an Altus Metrum device
2982 connected via USB, another Altus Metrum device can be
2983 reprogrammed using the supplied programming cable between the
2985 </p></li><li class="listitem"><p>
2986 Export Flight data to a comma-separated-values file. This takes
2987 either telemetry or on-board flight data and generates data
2988 suitable for use in external applications. All data is exported
2989 using standard units so that no device-specific knowledge is
2990 needed to handle the data.
2991 </p></li><li class="listitem"><p>
2992 Speak to you during the flight. Instead of spending the flight
2993 hunched over your laptop looking at the screen, enjoy the view
2994 while the computer tells you what’s going on up there. During
2995 ascent, you hear the current flight state and altitude
2996 information. During descent, you get azimuth, elevation and
2997 range information to try and help you find your rocket in the
2998 air. Once on the ground, the direction and distance are
3000 </p></li></ul></div></div></div></div></body></html>