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="idm15749952"></a>The Altus Metrum System</h1></div><div><h2 class="subtitle">An Owner's Manual for TeleMetrum, TeleMini, TeleDongle and TeleBT Devices</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="idp111792"></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 1.2.1</td><td align="left">21 May 2013</td></tr><tr><td align="left" colspan="2">
8 Updated for software version 1.2. Version 1.2 adds support
9 for TeleBT and AltosDroid. It also adds a few minor features
10 and fixes bugs in AltosUI and the AltOS firmware.
11 </td></tr><tr><td align="left">Revision 1.2</td><td align="left">18 April 2013</td></tr><tr><td align="left" colspan="2">
12 Updated for software version 1.2. Version 1.2 adds support
13 for MicroPeak and the MicroPeak USB interface.
14 </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">
15 Updated for software version 1.1.1 Version 1.1.1 fixes a few
16 bugs found in version 1.1.
17 </td></tr><tr><td align="left">Revision 1.1</td><td align="left">13 September 2012</td></tr><tr><td align="left" colspan="2">
18 Updated for software version 1.1. Version 1.1 has new
19 features but is otherwise compatible with version 1.0.
20 </td></tr><tr><td align="left">Revision 1.0</td><td align="left">24 August 2011</td></tr><tr><td align="left" colspan="2">
21 Updated for software version 1.0. Note that 1.0 represents a
22 telemetry format change, meaning both ends of a link
23 (TeleMetrum/TeleMini and TeleDongle) must be updated or
24 communications will fail.
25 </td></tr><tr><td align="left">Revision 0.9</td><td align="left">18 January 2011</td></tr><tr><td align="left" colspan="2">
26 Updated for software version 0.9. Note that 0.9 represents a
27 telemetry format change, meaning both ends of a link (TeleMetrum and
28 TeleDongle) must be updated or communications will fail.
29 </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="acknowledgements"><div class="titlepage"><div><div><h1 class="title"><a name="idp84128"></a>Acknowledgements</h1></div></div></div>
31 Thanks to Bob Finch, W9YA, NAR 12965, TRA 12350 for writing "The
32 Mere-Mortals Quick Start/Usage Guide to the Altus Metrum Starter
33 Kit" which formed the basis of the original Getting Started chapter
34 in this manual. Bob was one of our first customers for a production
35 TeleMetrum, and his continued enthusiasm and contributions
36 are immensely gratifying and highly appreciated!
39 And thanks to Anthony (AJ) Towns for major contributions including
40 the AltosUI graphing and site map code and associated documentation.
41 Free software means that our customers and friends can become our
42 collaborators, and we certainly appreciate this level of
46 Have fun using these products, and we hope to meet all of you
47 out on the rocket flight line somewhere.
48 </p><div class="literallayout"><p><br>
49 Bdale Garbee, KB0G<br>
50 NAR #87103, TRA #12201<br>
52 Keith Packard, KD7SQG<br>
53 NAR #88757, TRA #12200<br>
56 </div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="chapter"><a href="#idp45792">1. Introduction and Overview</a></span></dt><dt><span class="chapter"><a href="#idp49504">2. Getting Started</a></span></dt><dt><span class="chapter"><a href="#idp2493720">3. Handling Precautions</a></span></dt><dt><span class="chapter"><a href="#idp2765656">4. Hardware Overview</a></span></dt><dt><span class="chapter"><a href="#idp2919872">5. System Operation</a></span></dt><dd><dl><dt><span class="section"><a href="#idp2375600">1. Firmware Modes </a></span></dt><dt><span class="section"><a href="#idp2284648">2. GPS </a></span></dt><dt><span class="section"><a href="#idp753536">3. Controlling An Altimeter Over The Radio Link</a></span></dt><dt><span class="section"><a href="#idp760992">4. Ground Testing </a></span></dt><dt><span class="section"><a href="#idp762792">5. Radio Link </a></span></dt><dt><span class="section"><a href="#idp55640">6. Configurable Parameters</a></span></dt><dd><dl><dt><span class="section"><a href="#idp56488">6.1. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp57656">6.2. Apogee Delay</a></span></dt><dt><span class="section"><a href="#idp59488">6.3. Main Deployment Altitude</a></span></dt><dt><span class="section"><a href="#idp61128">6.4. Maximum Flight Log</a></span></dt><dt><span class="section"><a href="#idp64904">6.5. Ignite Mode</a></span></dt><dt><span class="section"><a href="#idp66248">6.6. Pad Orientation</a></span></dt></dl></dd></dl></dd><dt><span class="chapter"><a href="#idp67528">6. AltosUI</a></span></dt><dd><dl><dt><span class="section"><a href="#idp68608">1. Monitor Flight</a></span></dt><dd><dl><dt><span class="section"><a href="#idp75208">1.1. Launch Pad</a></span></dt><dt><span class="section"><a href="#idp3850840">1.2. Ascent</a></span></dt><dt><span class="section"><a href="#idp3852992">1.3. Descent</a></span></dt><dt><span class="section"><a href="#idp3856520">1.4. Landed</a></span></dt><dt><span class="section"><a href="#idp3859448">1.5. Site Map</a></span></dt></dl></dd><dt><span class="section"><a href="#idp3861728">2. Save Flight Data</a></span></dt><dt><span class="section"><a href="#idp3864648">3. Replay Flight</a></span></dt><dt><span class="section"><a href="#idp3865896">4. Graph Data</a></span></dt><dt><span class="section"><a href="#idp3869184">5. Export Data</a></span></dt><dd><dl><dt><span class="section"><a href="#idp3870192">5.1. Comma Separated Value Format</a></span></dt><dt><span class="section"><a href="#idp3871768">5.2. Keyhole Markup Language (for Google Earth)</a></span></dt></dl></dd><dt><span class="section"><a href="#idp3872600">6. Configure Altimeter</a></span></dt><dd><dl><dt><span class="section"><a href="#idp3876776">6.1. Main Deploy Altitude</a></span></dt><dt><span class="section"><a href="#idp3877760">6.2. Apogee Delay</a></span></dt><dt><span class="section"><a href="#idp3878800">6.3. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp3879712">6.4. Radio Calibration</a></span></dt><dt><span class="section"><a href="#idp3880776">6.5. Callsign</a></span></dt><dt><span class="section"><a href="#idp3881512">6.6. Maximum Flight Log Size</a></span></dt><dt><span class="section"><a href="#idp3882376">6.7. Ignite Mode</a></span></dt><dt><span class="section"><a href="#idp3885216">6.8. Pad Orientation</a></span></dt></dl></dd><dt><span class="section"><a href="#idp3887440">7. Configure AltosUI</a></span></dt><dd><dl><dt><span class="section"><a href="#idp3888064">7.1. Voice Settings</a></span></dt><dt><span class="section"><a href="#idp3890336">7.2. Log Directory</a></span></dt><dt><span class="section"><a href="#idp3891560">7.3. Callsign</a></span></dt><dt><span class="section"><a href="#idp3892528">7.4. Imperial Units</a></span></dt><dt><span class="section"><a href="#idp3893432">7.5. Font Size</a></span></dt><dt><span class="section"><a href="#idp3894136">7.6. Serial Debug</a></span></dt><dt><span class="section"><a href="#idp3895048">7.7. Manage Frequencies</a></span></dt></dl></dd><dt><span class="section"><a href="#idp3896032">8. Configure Groundstation</a></span></dt><dd><dl><dt><span class="section"><a href="#idp3899952">8.1. Frequency</a></span></dt><dt><span class="section"><a href="#idp3900936">8.2. Radio Calibration</a></span></dt></dl></dd><dt><span class="section"><a href="#idp3901928">9. Flash Image</a></span></dt><dt><span class="section"><a href="#idp3905000">10. Fire Igniter</a></span></dt><dt><span class="section"><a href="#idp3907104">11. Scan Channels</a></span></dt><dt><span class="section"><a href="#idp3908008">12. Load Maps</a></span></dt><dt><span class="section"><a href="#idp3910136">13. Monitor Idle</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp3911008">7. AltosDroid</a></span></dt><dd><dl><dt><span class="section"><a href="#idp3912688">1. Installing AltosDroid</a></span></dt><dt><span class="section"><a href="#idp3913648">2. Connecting to TeleBT</a></span></dt><dt><span class="section"><a href="#idp3914864">3. Configuring AltosDroid</a></span></dt><dt><span class="section"><a href="#idp3915736">4. Altos Droid Flight Monitoring</a></span></dt><dd><dl><dt><span class="section"><a href="#idp3916536">4.1. Pad</a></span></dt></dl></dd><dt><span class="section"><a href="#idp3922504">5. Downloading Flight Logs</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp3923520">8. Using Altus Metrum Products</a></span></dt><dd><dl><dt><span class="section"><a href="#idp3923840">1. Being Legal</a></span></dt><dt><span class="section"><a href="#idp3924800">2. In the Rocket</a></span></dt><dt><span class="section"><a href="#idp3926904">3. On the Ground</a></span></dt><dt><span class="section"><a href="#idp3934536">4. Data Analysis</a></span></dt><dt><span class="section"><a href="#idp3936288">5. Future Plans</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp3939448">9. Altimeter Installation Recommendations</a></span></dt><dd><dl><dt><span class="section"><a href="#idp3940432">1. Mounting the Altimeter</a></span></dt><dt><span class="section"><a href="#idp3942768">2. Dealing with the Antenna</a></span></dt><dt><span class="section"><a href="#idp3946752">3. Preserving GPS Reception</a></span></dt><dt><span class="section"><a href="#idp3949136">4. Radio Frequency Interference</a></span></dt><dt><span class="section"><a href="#idp3953208">5. The Barometric Sensor</a></span></dt><dt><span class="section"><a href="#idp3955048">6. Ground Testing</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp3957184">10. Updating Device Firmware</a></span></dt><dd><dl><dt><span class="section"><a href="#idp3959184">1. Updating TeleMetrum Firmware</a></span></dt><dt><span class="section"><a href="#idp3964528">2. Updating TeleMini Firmware</a></span></dt><dt><span class="section"><a href="#idp3969944">3. Updating TeleDongle Firmware</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp3977040">11. Hardware Specifications</a></span></dt><dd><dl><dt><span class="section"><a href="#idp3977360">1. TeleMetrum Specifications</a></span></dt><dt><span class="section"><a href="#idp3983088">2. TeleMini Specifications</a></span></dt></dl></dd><dt><span class="chapter"><a href="#idp3987896">12. FAQ</a></span></dt><dt><span class="appendix"><a href="#idp3991640">A. Notes for Older Software</a></span></dt><dt><span class="appendix"><a href="#idp4008072">B. Drill Templates</a></span></dt><dd><dl><dt><span class="section"><a href="#idp4008720">1. TeleMetrum template</a></span></dt><dt><span class="section"><a href="#idp4016464">2. TeleMini template</a></span></dt></dl></dd><dt><span class="appendix"><a href="#idp4018112">C. Calibration</a></span></dt><dd><dl><dt><span class="section"><a href="#idp4019088">1. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp4022408">2. TeleMetrum Accelerometer</a></span></dt></dl></dd><dt><span class="appendix"><a href="#idp4027304">D. Release Notes</a></span></dt></dl></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp45792"></a>Chapter 1. Introduction and Overview</h1></div></div></div><p>
57 Welcome to the Altus Metrum community! Our circuits and software reflect
58 our passion for both hobby rocketry and Free Software. We hope their
59 capabilities and performance will delight you in every way, but by
60 releasing all of our hardware and software designs under open licenses,
61 we also hope to empower you to take as active a role in our collective
64 The first device created for our community was TeleMetrum, a dual
65 deploy altimeter with fully integrated GPS and radio telemetry
66 as standard features, and a "companion interface" that will
67 support optional capabilities in the future.
69 Our second device was TeleMini, a dual deploy altimeter with
70 radio telemetry and radio direction finding. This device is only
71 13mm by 38mm (½ inch by 1½ inches) and can fit easily in an 18mm
74 TeleDongle was our first ground station, providing a USB to RF
75 interfaces for communicating with the altimeters. Combined with
76 your choice of antenna and notebook computer, TeleDongle and our
77 associated user interface software form a complete ground
78 station capable of logging and displaying in-flight telemetry,
79 aiding rocket recovery, then processing and archiving flight
80 data for analysis and review.
82 For a slightly more portable ground station experience that also
83 provides direct rocket recovery support, TeleBT offers flight
84 monitoring and data logging using a Bluetooth connection between
85 the receiver and an Android device that has the Altos Droid
86 application installed from the Google Play store.
88 More products will be added to the Altus Metrum family over time, and
89 we currently envision that this will be a single, comprehensive manual
90 for the entire product family.
91 </p></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp49504"></a>Chapter 2. Getting Started</h1></div></div></div><p>
92 The first thing to do after you check the inventory of parts in your
93 "starter kit" is to charge the battery.
95 The TeleMetrum battery can be charged by plugging it into the
96 corresponding socket of the TeleMetrum and then using the USB A to
98 cable to plug the TeleMetrum into your computer's USB socket. The
99 TeleMetrum circuitry will charge the battery whenever it is plugged
100 in, because the TeleMetrum's on-off switch does NOT control the
103 When the GPS chip is initially searching for
104 satellites, TeleMetrum will consume more current than it can pull
105 from the USB port, so the battery must be attached in order to get
106 satellite lock. Once GPS is locked, the current consumption goes back
107 down enough to enable charging while
108 running. So it's a good idea to fully charge the battery as your
109 first item of business so there is no issue getting and maintaining
110 satellite lock. The yellow charge indicator led will go out when the
111 battery is nearly full and the charger goes to trickle charge. It
112 can take several hours to fully recharge a deeply discharged battery.
114 The TeleMini battery can be charged by disconnecting it from the
115 TeleMini board and plugging it into a standalone battery charger
116 such as the LipoCharger product included in TeleMini Starter Kits,
117 and connecting that via a USB cable to a laptop or other USB
120 The other active device in the starter kit is the TeleDongle USB to
121 RF interface. If you plug it in to your Mac or Linux computer it should
122 "just work", showing up as a serial port device. Windows systems need
123 driver information that is part of the AltOS download to know that the
124 existing USB modem driver will work. We therefore recommend installing
125 our software before plugging in TeleDongle if you are using a Windows
126 computer. If you are using Linux and are having problems, try moving
127 to a fresher kernel (2.6.33 or newer), as the USB serial driver had
128 ugly bugs in some earlier versions.
130 Next you should obtain and install the AltOS software. These include
131 the AltosUI ground station program, current firmware images for
132 TeleMetrum, TeleMini and TeleDongle, and a number of standalone
133 utilities that are rarely needed. Pre-built binary packages are
134 available for Linux, Microsoft Windows, and recent MacOSX versions.
135 Full source code and build instructions are also available.
136 The latest version may always be downloaded from
137 <a class="ulink" href="http://altusmetrum.org/AltOS" target="_top">http://altusmetrum.org/AltOS</a>.
139 If you're using a TeleBT instead of the TeleDongle, you'll want
140 to go install the Altos Droid application from the Google Play
141 store. You don't need a data plan to use Altos Droid, but
142 without network access, the Map view will be less useful as it
143 won't contain any map data. You can also use TeleBT connected
144 over USB with your laptop computer; it acts exactly like a
145 TeleDongle. Anywhere this manual talks about TeleDongle, you can
146 also read that as 'and TeleBT when connected via USB'.
147 </p></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp2493720"></a>Chapter 3. Handling Precautions</h1></div></div></div><p>
148 All Altus Metrum products are sophisticated electronic devices.
149 When handled gently and properly installed in an air-frame, they
150 will deliver impressive results. However, as with all electronic
151 devices, there are some precautions you must take.
153 The Lithium Polymer rechargeable batteries have an
154 extraordinary power density. This is great because we can fly with
155 much less battery mass than if we used alkaline batteries or previous
156 generation rechargeable batteries... but if they are punctured
157 or their leads are allowed to short, they can and will release their
159 Thus we recommend that you take some care when handling our batteries
160 and consider giving them some extra protection in your air-frame. We
161 often wrap them in suitable scraps of closed-cell packing foam before
162 strapping them down, for example.
164 The barometric sensors used on both TeleMetrum and TeleMini are
165 sensitive to sunlight. In normal TeleMetrum mounting situations, it
166 and all of the other surface mount components
167 are "down" towards whatever the underlying mounting surface is, so
168 this is not normally a problem. Please consider this, though, when
169 designing an installation, for example, in an air-frame with a
170 see-through plastic payload bay. It is particularly important to
171 consider this with TeleMini, both because the baro sensor is on the
172 "top" of the board, and because many model rockets with payload bays
173 use clear plastic for the payload bay! Replacing these with an opaque
174 cardboard tube, painting them, or wrapping them with a layer of masking
175 tape are all reasonable approaches to keep the sensor out of direct
178 The barometric sensor sampling port must be able to "breathe",
179 both by not being covered by foam or tape or other materials that might
180 directly block the hole on the top of the sensor, and also by having a
181 suitable static vent to outside air.
183 As with all other rocketry electronics, Altus Metrum altimeters must
184 be protected from exposure to corrosive motor exhaust and ejection
186 </p></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp2765656"></a>Chapter 4. Hardware Overview</h1></div></div></div><p>
187 TeleMetrum is a 1 inch by 2.75 inch circuit board. It was designed to
188 fit inside coupler for 29mm air-frame tubing, but using it in a tube that
189 small in diameter may require some creativity in mounting and wiring
190 to succeed! The presence of an accelerometer means TeleMetrum should
191 be aligned along the flight axis of the airframe, and by default the 1/4
192 wave UHF wire antenna should be on the nose-cone end of the board. The
193 antenna wire is about 7 inches long, and wiring for a power switch and
194 the e-matches for apogee and main ejection charges depart from the
195 fin can end of the board, meaning an ideal "simple" avionics
196 bay for TeleMetrum should have at least 10 inches of interior length.
198 TeleMini is a 0.5 inch by 1.5 inch circuit board. It was designed to
199 fit inside an 18mm air-frame tube, but using it in a tube that
200 small in diameter may require some creativity in mounting and wiring
201 to succeed! Since there is no accelerometer, TeleMini can be mounted
202 in any convenient orientation. The default 1/4
203 wave UHF wire antenna attached to the center of one end of
204 the board is about 7 inches long, and wiring for a power switch and
205 the e-matches for apogee and main ejection charges depart from the
206 other end of the board, meaning an ideal "simple" avionics
207 bay for TeleMini should have at least 9 inches of interior length.
209 A typical TeleMetrum or TeleMini installation involves attaching
210 only a suitable Lithium Polymer battery, a single pole switch for
211 power on/off, and two pairs of wires connecting e-matches for the
212 apogee and main ejection charges. All Altus Metrum products are
213 designed for use with single-cell batteries with 3.7 volts nominal.
215 The battery connectors are a standard 2-pin JST connector and
216 match batteries sold by Spark Fun. These batteries are
217 single-cell Lithium Polymer batteries that nominally provide 3.7
218 volts. Other vendors sell similar batteries for RC aircraft
219 using mating connectors, however the polarity for those is
220 generally reversed from the batteries used by Altus Metrum
221 products. In particular, the Tenergy batteries supplied for use
222 in Featherweight flight computers are not compatible with Altus
223 Metrum flight computers or battery chargers. <span class="emphasis"><em>Check
224 polarity and voltage before connecting any battery not purchased
225 from Altus Metrum or Spark Fun.</em></span>
227 By default, we use the unregulated output of the Li-Po battery directly
228 to fire ejection charges. This works marvelously with standard
229 low-current e-matches like the J-Tek from MJG Technologies, and with
230 Quest Q2G2 igniters. However, if you want or need to use a separate
231 pyro battery, check out the "External Pyro Battery" section in this
232 manual for instructions on how to wire that up. The altimeters are
233 designed to work with an external pyro battery of no more than 15 volts.
235 Ejection charges are wired directly to the screw terminal block
236 at the aft end of the altimeter. You'll need a very small straight
237 blade screwdriver for these screws, such as you might find in a
238 jeweler's screwdriver set.
240 TeleMetrum also uses the screw terminal block for the power
241 switch leads. On TeleMini, the power switch leads are soldered
242 directly to the board and can be connected directly to a switch.
244 For most air-frames, the integrated antennas are more than
245 adequate. However, if you are installing in a carbon-fiber or
246 metal electronics bay which is opaque to RF signals, you may need to
247 use off-board external antennas instead. In this case, you can
248 order an altimeter with an SMA connector for the UHF antenna
249 connection, and, on TeleMetrum, you can unplug the integrated GPS
250 antenna and select an appropriate off-board GPS antenna with
251 cable terminating in a U.FL connector.
252 </p></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp2919872"></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="#idp2375600">1. Firmware Modes </a></span></dt><dt><span class="section"><a href="#idp2284648">2. GPS </a></span></dt><dt><span class="section"><a href="#idp753536">3. Controlling An Altimeter Over The Radio Link</a></span></dt><dt><span class="section"><a href="#idp760992">4. Ground Testing </a></span></dt><dt><span class="section"><a href="#idp762792">5. Radio Link </a></span></dt><dt><span class="section"><a href="#idp55640">6. Configurable Parameters</a></span></dt><dd><dl><dt><span class="section"><a href="#idp56488">6.1. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp57656">6.2. Apogee Delay</a></span></dt><dt><span class="section"><a href="#idp59488">6.3. Main Deployment Altitude</a></span></dt><dt><span class="section"><a href="#idp61128">6.4. Maximum Flight Log</a></span></dt><dt><span class="section"><a href="#idp64904">6.5. Ignite Mode</a></span></dt><dt><span class="section"><a href="#idp66248">6.6. Pad Orientation</a></span></dt></dl></dd></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp2375600"></a>1. Firmware Modes </h2></div></div></div><p>
253 The AltOS firmware build for the altimeters has two
254 fundamental modes, "idle" and "flight". Which of these modes
255 the firmware operates in is determined at start up time. For
256 TeleMetrum, the mode is controlled by the orientation of the
257 rocket (well, actually the board, of course...) at the time
258 power is switched on. If the rocket is "nose up", then
259 TeleMetrum assumes it's on a rail or rod being prepared for
260 launch, so the firmware chooses flight mode. However, if the
261 rocket is more or less horizontal, the firmware instead enters
262 idle mode. Since TeleMini doesn't have an accelerometer we can
263 use to determine orientation, "idle" mode is selected when the
264 board receives a command packet within the first five seconds
265 of operation; if no packet is received, the board enters
268 At power on, you will hear three beeps or see three flashes
269 ("S" in Morse code for start up) and then a pause while
270 the altimeter completes initialization and self test, and decides
271 which mode to enter next.
273 In flight or "pad" mode, the altimeter engages the flight
274 state machine, goes into transmit-only mode to
275 send telemetry, and waits for launch to be detected.
276 Flight mode is indicated by an "di-dah-dah-dit" ("P" for pad)
277 on the beeper or lights, followed by beeps or flashes
278 indicating the state of the pyrotechnic igniter continuity.
279 One beep/flash indicates apogee continuity, two beeps/flashes
280 indicate main continuity, three beeps/flashes indicate both
281 apogee and main continuity, and one longer "brap" sound or
282 rapidly alternating lights indicates no continuity. For a
283 dual deploy flight, make sure you're getting three beeps or
284 flashes before launching! For apogee-only or motor eject
285 flights, do what makes sense.
287 If idle mode is entered, you will hear an audible "di-dit" or
288 see two short flashes ("I" for idle), and the flight state
289 machine is disengaged, thus no ejection charges will fire.
290 The altimeters also listen for the radio link when in idle
291 mode for requests sent via TeleDongle. Commands can be issued
292 to a TeleMetrum in idle mode over either USB or the radio link
293 equivalently. TeleMini only has the radio link. Idle mode is
294 useful for configuring the altimeter, for extracting data from
295 the on-board storage chip after flight, and for ground testing
298 One "neat trick" of particular value when TeleMetrum is used with
299 very large air-frames, is that you can power the board up while the
300 rocket is horizontal, such that it comes up in idle mode. Then you can
301 raise the air-frame to launch position, and issue a 'reset' command
302 via TeleDongle over the radio link to cause the altimeter to reboot and
303 come up in flight mode. This is much safer than standing on the top
304 step of a rickety step-ladder or hanging off the side of a launch
305 tower with a screw-driver trying to turn on your avionics before
308 TeleMini is configured via the radio link. Of course, that
309 means you need to know the TeleMini radio configuration values
310 or you won't be able to communicate with it. For situations
311 when you don't have the radio configuration values, TeleMini
312 offers an 'emergency recovery' mode. In this mode, TeleMini is
313 configured as follows:
314 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
315 Sets the radio frequency to 434.550MHz
316 </li><li class="listitem">
317 Sets the radio calibration back to the factory value.
318 </li><li class="listitem">
319 Sets the callsign to N0CALL
320 </li><li class="listitem">
321 Does not go to 'pad' mode after five seconds.
324 To get into 'emergency recovery' mode, first find the row of
325 four small holes opposite the switch wiring. Using a short
326 piece of small gauge wire, connect the outer two holes
327 together, then power TeleMini up. Once the red LED is lit,
328 disconnect the wire and the board should signal that it's in
329 'idle' mode after the initial five second startup period.
330 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp2284648"></a>2. GPS </h2></div></div></div><p>
331 TeleMetrum includes a complete GPS receiver. A complete explanation
332 of how GPS works is beyond the scope of this manual, but the bottom
333 line is that the TeleMetrum GPS receiver needs to lock onto at least
334 four satellites to obtain a solid 3 dimensional position fix and know
337 TeleMetrum provides backup power to the GPS chip any time a
338 battery is connected. This allows the receiver to "warm start" on
339 the launch rail much faster than if every power-on were a GPS
340 "cold start". In typical operations, powering up TeleMetrum
341 on the flight line in idle mode while performing final air-frame
342 preparation will be sufficient to allow the GPS receiver to cold
343 start and acquire lock. Then the board can be powered down during
344 RSO review and installation on a launch rod or rail. When the board
345 is turned back on, the GPS system should lock very quickly, typically
346 long before igniter installation and return to the flight line are
348 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp753536"></a>3. Controlling An Altimeter Over The Radio Link</h2></div></div></div><p>
349 One of the unique features of the Altus Metrum system is the
350 ability to create a two way command link between TeleDongle
351 and an altimeter using the digital radio transceivers
352 built into each device. This allows you to interact with the
353 altimeter from afar, as if it were directly connected to the
356 Any operation which can be performed with TeleMetrum can
357 either be done with TeleMetrum directly connected to the
358 computer via the USB cable, or through the radio
359 link. TeleMini doesn't provide a USB connector and so it is
360 always communicated with over radio. Select the appropriate
361 TeleDongle device when the list of devices is presented and
362 AltosUI will interact with an altimeter over the radio link.
364 One oddity in the current interface is how AltosUI selects the
365 frequency for radio communications. Instead of providing
366 an interface to specifically configure the frequency, it uses
367 whatever frequency was most recently selected for the target
368 TeleDongle device in Monitor Flight mode. If you haven't ever
369 used that mode with the TeleDongle in question, select the
370 Monitor Flight button from the top level UI, and pick the
371 appropriate TeleDongle device. Once the flight monitoring
372 window is open, select the desired frequency and then close it
373 down again. All radio communications will now use that frequency.
374 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
375 Save Flight Data—Recover flight data from the rocket without
377 </p></li><li class="listitem"><p>
378 Configure altimeter apogee delays or main deploy heights
379 to respond to changing launch conditions. You can also
380 'reboot' the altimeter. Use this to remotely enable the
381 flight computer by turning TeleMetrum on in "idle" mode,
382 then once the air-frame is oriented for launch, you can
383 reboot the altimeter and have it restart in pad mode
384 without having to climb the scary ladder.
385 </p></li><li class="listitem"><p>
386 Fire Igniters—Test your deployment charges without snaking
387 wires out through holes in the air-frame. Simply assembly the
388 rocket as if for flight with the apogee and main charges
389 loaded, then remotely command the altimeter to fire the
391 </p></li></ul></div><p>
392 Operation over the radio link for configuring an altimeter, ground
393 testing igniters, and so forth uses the same RF frequencies as flight
394 telemetry. To configure the desired TeleDongle frequency, select
395 the monitor flight tab, then use the frequency selector and
396 close the window before performing other desired radio operations.
398 TeleMetrum only enables radio commanding in 'idle' mode, so
399 make sure you have TeleMetrum lying horizontally when you turn
400 it on. Otherwise, TeleMetrum will start in 'pad' mode ready for
401 flight, and will not be listening for command packets from TeleDongle.
403 TeleMini listens for a command packet for five seconds after
404 first being turned on, if it doesn't hear anything, it enters
405 'pad' mode, ready for flight and will no longer listen for
406 command packets. The easiest way to connect to TeleMini is to
407 initiate the command and select the TeleDongle device. At this
408 point, the TeleDongle will be attempting to communicate with
409 the TeleMini. Now turn TeleMini on, and it should immediately
410 start communicating with the TeleDongle and the desired
411 operation can be performed.
413 You can monitor the operation of the radio link by watching the
414 lights on the devices. The red LED will flash each time a packet
415 is transmitted, while the green LED will light up on TeleDongle when
416 it is waiting to receive a packet from the altimeter.
417 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp760992"></a>4. Ground Testing </h2></div></div></div><p>
418 An important aspect of preparing a rocket using electronic deployment
419 for flight is ground testing the recovery system. Thanks
420 to the bi-directional radio link central to the Altus Metrum system,
421 this can be accomplished in a TeleMetrum or TeleMini equipped rocket
422 with less work than you may be accustomed to with other systems. It
425 Just prep the rocket for flight, then power up the altimeter
426 in "idle" mode (placing air-frame horizontal for TeleMetrum or
427 selected the Configure Altimeter tab for TeleMini). This will cause
428 the firmware to go into "idle" mode, in which the normal flight
429 state machine is disabled and charges will not fire without
430 manual command. You can now command the altimeter to fire the apogee
431 or main charges from a safe distance using your computer and
432 TeleDongle and the Fire Igniter tab to complete ejection testing.
433 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp762792"></a>5. Radio Link </h2></div></div></div><p>
434 The chip our boards are based on incorporates an RF transceiver, but
435 it's not a full duplex system... each end can only be transmitting or
436 receiving at any given moment. So we had to decide how to manage the
439 By design, the altimeter firmware listens for the radio link when
440 it's in "idle mode", which
441 allows us to use the radio link to configure the rocket, do things like
442 ejection tests, and extract data after a flight without having to
443 crack open the air-frame. However, when the board is in "flight
444 mode", the altimeter only
445 transmits and doesn't listen at all. That's because we want to put
446 ultimate priority on event detection and getting telemetry out of
448 the radio in case the rocket crashes and we aren't able to extract
451 We don't use a 'normal packet radio' mode like APRS because they're
452 just too inefficient. The GFSK modulation we use is FSK with the
453 base-band pulses passed through a
454 Gaussian filter before they go into the modulator to limit the
455 transmitted bandwidth. When combined with the hardware forward error
456 correction support in the cc1111 chip, this allows us to have a very
457 robust 38.4 kilobit data link with only 10 milliwatts of transmit
458 power, a whip antenna in the rocket, and a hand-held Yagi on the
459 ground. We've had flights to above 21k feet AGL with great reception,
460 and calculations suggest we should be good to well over 40k feet AGL
461 with a 5-element yagi on the ground. We hope to fly boards to higher
462 altitudes over time, and would of course appreciate customer feedback
463 on performance in higher altitude flights!
464 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp55640"></a>6. Configurable Parameters</h2></div></div></div><p>
465 Configuring an Altus Metrum altimeter for flight is very
466 simple. Even on our baro-only TeleMini board, the use of a Kalman
467 filter means there is no need to set a "mach delay". The few
468 configurable parameters can all be set using AltosUI over USB or
469 or radio link via TeleDongle.
470 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp56488"></a>6.1. Radio Frequency</h3></div></div></div><p>
471 Altus Metrum boards support radio frequencies in the 70cm
472 band. By default, the configuration interface provides a
473 list of 10 "standard" frequencies in 100kHz channels starting at
474 434.550MHz. However, the firmware supports use of
475 any 50kHz multiple within the 70cm band. At any given
476 launch, we highly recommend coordinating when and by whom each
477 frequency will be used to avoid interference. And of course, both
478 altimeter and TeleDongle must be configured to the same
479 frequency to successfully communicate with each other.
480 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp57656"></a>6.2. Apogee Delay</h3></div></div></div><p>
481 Apogee delay is the number of seconds after the altimeter detects flight
482 apogee that the drogue charge should be fired. In most cases, this
483 should be left at the default of 0. However, if you are flying
484 redundant electronics such as for an L3 certification, you may wish
485 to set one of your altimeters to a positive delay so that both
486 primary and backup pyrotechnic charges do not fire simultaneously.
488 The Altus Metrum apogee detection algorithm fires exactly at
489 apogee. If you are also flying an altimeter like the
490 PerfectFlite MAWD, which only supports selecting 0 or 1
491 seconds of apogee delay, you may wish to set the MAWD to 0
492 seconds delay and set the TeleMetrum to fire your backup 2
493 or 3 seconds later to avoid any chance of both charges
494 firing simultaneously. We've flown several air-frames this
495 way quite happily, including Keith's successful L3 cert.
496 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp59488"></a>6.3. Main Deployment Altitude</h3></div></div></div><p>
497 By default, the altimeter will fire the main deployment charge at an
498 elevation of 250 meters (about 820 feet) above ground. We think this
499 is a good elevation for most air-frames, but feel free to change this
500 to suit. In particular, if you are flying two altimeters, you may
502 deployment elevation for the backup altimeter to be something lower
503 than the primary so that both pyrotechnic charges don't fire
505 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp61128"></a>6.4. Maximum Flight Log</h3></div></div></div><p>
506 TeleMetrum version 1.1 and 1.2 have 2MB of on-board flash storage,
507 enough to hold over 40 minutes of data at full data rate
508 (100 samples/second). TeleMetrum 1.0 has 1MB of on-board
509 storage. As data are stored at a reduced rate during descent
510 (10 samples/second), there's plenty of space to store many
511 flights worth of data.
513 The on-board flash is partitioned into separate flight logs,
514 each of a fixed maximum size. Increase the maximum size of
515 each log and you reduce the number of flights that can be
516 stored. Decrease the size and TeleMetrum can store more
519 All of the configuration data is also stored in the flash
520 memory, which consumes 64kB on TeleMetrum v1.1/v1.2 and 256B on
521 TeleMetrum v1.0. This configuration space is not available
522 for storing flight log data.
524 To compute the amount of space needed for a single flight,
525 you can multiply the expected ascent time (in seconds) by
526 800, multiply the expected descent time (in seconds) by 80
527 and add the two together. That will slightly under-estimate
528 the storage (in bytes) needed for the flight. For instance,
529 a flight spending 20 seconds in ascent and 150 seconds in
530 descent will take about (20 * 800) + (150 * 80) = 28000
531 bytes of storage. You could store dozens of these flights in
534 The default size, 192kB, allows for 10 flights of storage on
535 TeleMetrum v1.1/v1.2 and 5 flights on TeleMetrum v1.0. This
536 ensures that you won't need to erase the memory before
537 flying each time while still allowing more than sufficient
538 storage for each flight.
540 As TeleMini does not contain an accelerometer, it stores
541 data at 10 samples per second during ascent and one sample
542 per second during descent. Each sample is a two byte reading
543 from the barometer. These are stored in 5kB of
544 on-chip flash memory which can hold 256 seconds at the
545 ascent rate or 2560 seconds at the descent rate. Because of
546 the limited storage, TeleMini cannot hold data for more than
547 one flight, and so must be erased after each flight or it
548 will not capture data for subsequent flights.
549 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp64904"></a>6.5. Ignite Mode</h3></div></div></div><p>
550 Instead of firing one charge at apogee and another charge at
551 a fixed height above the ground, you can configure the
552 altimeter to fire both at apogee or both during
553 descent. This was added to support an airframe that has two
554 TeleMetrum computers, one in the fin can and one in the
557 Providing the ability to use both igniters for apogee or
558 main allows some level of redundancy without needing two
559 flight computers. In Redundant Apogee or Redundant Main
560 mode, the two charges will be fired two seconds apart.
561 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp66248"></a>6.6. Pad Orientation</h3></div></div></div><p>
562 TeleMetrum measures acceleration along the axis of the
563 board. Which way the board is oriented affects the sign of
564 the acceleration value. Instead of trying to guess which way
565 the board is mounted in the air frame, TeleMetrum must be
566 explicitly configured for either Antenna Up or Antenna
567 Down. The default, Antenna Up, expects the end of the
568 TeleMetrum board connected to the 70cm antenna to be nearest
569 the nose of the rocket, with the end containing the screw
570 terminals nearest the tail.
571 </p></div></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp67528"></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="#idp68608">1. Monitor Flight</a></span></dt><dd><dl><dt><span class="section"><a href="#idp75208">1.1. Launch Pad</a></span></dt><dt><span class="section"><a href="#idp3850840">1.2. Ascent</a></span></dt><dt><span class="section"><a href="#idp3852992">1.3. Descent</a></span></dt><dt><span class="section"><a href="#idp3856520">1.4. Landed</a></span></dt><dt><span class="section"><a href="#idp3859448">1.5. Site Map</a></span></dt></dl></dd><dt><span class="section"><a href="#idp3861728">2. Save Flight Data</a></span></dt><dt><span class="section"><a href="#idp3864648">3. Replay Flight</a></span></dt><dt><span class="section"><a href="#idp3865896">4. Graph Data</a></span></dt><dt><span class="section"><a href="#idp3869184">5. Export Data</a></span></dt><dd><dl><dt><span class="section"><a href="#idp3870192">5.1. Comma Separated Value Format</a></span></dt><dt><span class="section"><a href="#idp3871768">5.2. Keyhole Markup Language (for Google Earth)</a></span></dt></dl></dd><dt><span class="section"><a href="#idp3872600">6. Configure Altimeter</a></span></dt><dd><dl><dt><span class="section"><a href="#idp3876776">6.1. Main Deploy Altitude</a></span></dt><dt><span class="section"><a href="#idp3877760">6.2. Apogee Delay</a></span></dt><dt><span class="section"><a href="#idp3878800">6.3. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp3879712">6.4. Radio Calibration</a></span></dt><dt><span class="section"><a href="#idp3880776">6.5. Callsign</a></span></dt><dt><span class="section"><a href="#idp3881512">6.6. Maximum Flight Log Size</a></span></dt><dt><span class="section"><a href="#idp3882376">6.7. Ignite Mode</a></span></dt><dt><span class="section"><a href="#idp3885216">6.8. Pad Orientation</a></span></dt></dl></dd><dt><span class="section"><a href="#idp3887440">7. Configure AltosUI</a></span></dt><dd><dl><dt><span class="section"><a href="#idp3888064">7.1. Voice Settings</a></span></dt><dt><span class="section"><a href="#idp3890336">7.2. Log Directory</a></span></dt><dt><span class="section"><a href="#idp3891560">7.3. Callsign</a></span></dt><dt><span class="section"><a href="#idp3892528">7.4. Imperial Units</a></span></dt><dt><span class="section"><a href="#idp3893432">7.5. Font Size</a></span></dt><dt><span class="section"><a href="#idp3894136">7.6. Serial Debug</a></span></dt><dt><span class="section"><a href="#idp3895048">7.7. Manage Frequencies</a></span></dt></dl></dd><dt><span class="section"><a href="#idp3896032">8. Configure Groundstation</a></span></dt><dd><dl><dt><span class="section"><a href="#idp3899952">8.1. Frequency</a></span></dt><dt><span class="section"><a href="#idp3900936">8.2. Radio Calibration</a></span></dt></dl></dd><dt><span class="section"><a href="#idp3901928">9. Flash Image</a></span></dt><dt><span class="section"><a href="#idp3905000">10. Fire Igniter</a></span></dt><dt><span class="section"><a href="#idp3907104">11. Scan Channels</a></span></dt><dt><span class="section"><a href="#idp3908008">12. Load Maps</a></span></dt><dt><span class="section"><a href="#idp3910136">13. Monitor Idle</a></span></dt></dl></div><p>
572 The AltosUI program provides a graphical user interface for
573 interacting with the Altus Metrum product family, including
574 TeleMetrum, TeleMini and TeleDongle. AltosUI can monitor telemetry data,
575 configure TeleMetrum, TeleMini and TeleDongle devices and many other
576 tasks. The primary interface window provides a selection of
577 buttons, one for each major activity in the system. This manual
578 is split into chapters, each of which documents one of the tasks
579 provided from the top-level toolbar.
580 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp68608"></a>1. Monitor Flight</h2></div><div><h3 class="subtitle">Receive, Record and Display Telemetry Data</h3></div></div></div><p>
581 Selecting this item brings up a dialog box listing all of the
582 connected TeleDongle devices. When you choose one of these,
583 AltosUI will create a window to display telemetry data as
584 received by the selected TeleDongle device.
586 All telemetry data received are automatically recorded in
587 suitable log files. The name of the files includes the current
588 date and rocket serial and flight numbers.
590 The radio frequency being monitored by the TeleDongle device is
591 displayed at the top of the window. You can configure the
592 frequency by clicking on the frequency box and selecting the desired
593 frequency. AltosUI remembers the last frequency selected for each
594 TeleDongle and selects that automatically the next time you use
597 Below the TeleDongle frequency selector, the window contains a few
598 significant pieces of information about the altimeter providing
599 the telemetry data stream:
600 </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
602 </p></li><li class="listitem"><p>
603 The rocket flight state. Each flight passes through several
604 states including Pad, Boost, Fast, Coast, Drogue, Main and
606 </p></li><li class="listitem"><p>
607 The Received Signal Strength Indicator value. This lets
608 you know how strong a signal TeleDongle is receiving. The
609 radio inside TeleDongle operates down to about -99dBm;
610 weaker signals may not be receivable. The packet link uses
611 error detection and correction techniques which prevent
612 incorrect data from being reported.
613 </p></li><li class="listitem"><p>
614 The age of the displayed data, in seconds since the last
615 successfully received telemetry packet. In normal operation
616 this will stay in the low single digits. If the number starts
617 counting up, then you are no longer receiving data over the radio
618 link from the flight computer.
619 </p></li></ul></div><p>
620 Finally, the largest portion of the window contains a set of
621 tabs, each of which contain some information about the rocket.
622 They're arranged in 'flight order' so that as the flight
623 progresses, the selected tab automatically switches to display
624 data relevant to the current state of the flight. You can select
625 other tabs at any time. The final 'table' tab displays all of
626 the raw telemetry values in one place in a spreadsheet-like format.
627 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp75208"></a>1.1. Launch Pad</h3></div></div></div><p>
628 The 'Launch Pad' tab shows information used to decide when the
629 rocket is ready for flight. The first elements include red/green
630 indicators, if any of these is red, you'll want to evaluate
631 whether the rocket is ready to launch:
632 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
633 Battery Voltage. This indicates whether the Li-Po battery
634 powering the TeleMetrum has sufficient charge to last for
635 the duration of the flight. A value of more than
636 3.7V is required for a 'GO' status.
637 </p></li><li class="listitem"><p>
638 Apogee Igniter Voltage. This indicates whether the apogee
639 igniter has continuity. If the igniter has a low
640 resistance, then the voltage measured here will be close
641 to the Li-Po battery voltage. A value greater than 3.2V is
642 required for a 'GO' status.
643 </p></li><li class="listitem"><p>
644 Main Igniter Voltage. This indicates whether the main
645 igniter has continuity. If the igniter has a low
646 resistance, then the voltage measured here will be close
647 to the Li-Po battery voltage. A value greater than 3.2V is
648 required for a 'GO' status.
649 </p></li><li class="listitem"><p>
650 On-board Data Logging. This indicates whether there is
651 space remaining on-board to store flight data for the
652 upcoming flight. If you've downloaded data, but failed
653 to erase flights, there may not be any space
654 left. TeleMetrum can store multiple flights, depending
655 on the configured maximum flight log size. TeleMini
656 stores only a single flight, so it will need to be
657 downloaded and erased after each flight to capture
658 data. This only affects on-board flight logging; the
659 altimeter will still transmit telemetry and fire
660 ejection charges at the proper times.
661 </p></li><li class="listitem"><p>
662 GPS Locked. For a TeleMetrum device, this indicates whether the GPS receiver is
663 currently able to compute position information. GPS requires
664 at least 4 satellites to compute an accurate position.
665 </p></li><li class="listitem"><p>
666 GPS Ready. For a TeleMetrum device, this indicates whether GPS has reported at least
667 10 consecutive positions without losing lock. This ensures
668 that the GPS receiver has reliable reception from the
670 </p></li></ul></div><p>
672 The Launchpad tab also shows the computed launch pad position
673 and altitude, averaging many reported positions to improve the
676 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3850840"></a>1.2. Ascent</h3></div></div></div><p>
677 This tab is shown during Boost, Fast and Coast
678 phases. The information displayed here helps monitor the
679 rocket as it heads towards apogee.
681 The height, speed and acceleration are shown along with the
682 maximum values for each of them. This allows you to quickly
683 answer the most commonly asked questions you'll hear during
686 The current latitude and longitude reported by the TeleMetrum GPS are
687 also shown. Note that under high acceleration, these values
688 may not get updated as the GPS receiver loses position
689 fix. Once the rocket starts coasting, the receiver should
690 start reporting position again.
692 Finally, the current igniter voltages are reported as in the
693 Launch Pad tab. This can help diagnose deployment failures
694 caused by wiring which comes loose under high acceleration.
695 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3852992"></a>1.3. Descent</h3></div></div></div><p>
696 Once the rocket has reached apogee and (we hope) activated the
697 apogee charge, attention switches to tracking the rocket on
698 the way back to the ground, and for dual-deploy flights,
699 waiting for the main charge to fire.
701 To monitor whether the apogee charge operated correctly, the
702 current descent rate is reported along with the current
703 height. Good descent rates vary based on the choice of recovery
704 components, but generally range from 15-30m/s on drogue and should
705 be below 10m/s when under the main parachute in a dual-deploy flight.
707 For TeleMetrum altimeters, you can locate the rocket in the
708 sky using the elevation and bearing information to figure
709 out where to look. Elevation is in degrees above the
710 horizon. Bearing is reported in degrees relative to true
711 north. Range can help figure out how big the rocket will
712 appear. Ground Distance shows how far it is to a point
713 directly under the rocket and can help figure out where the
714 rocket is likely to land. Note that all of these values are
715 relative to the pad location. If the elevation is near 90°,
716 the rocket is over the pad, not over you.
718 Finally, the igniter voltages are reported in this tab as
719 well, both to monitor the main charge as well as to see what
720 the status of the apogee charge is. Note that some commercial
721 e-matches are designed to retain continuity even after being
722 fired, and will continue to show as green or return from red to
724 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3856520"></a>1.4. Landed</h3></div></div></div><p>
725 Once the rocket is on the ground, attention switches to
726 recovery. While the radio signal is often lost once the
727 rocket is on the ground, the last reported GPS position is
728 generally within a short distance of the actual landing location.
730 The last reported GPS position is reported both by
731 latitude and longitude as well as a bearing and distance from
732 the launch pad. The distance should give you a good idea of
733 whether to walk or hitch a ride. Take the reported
734 latitude and longitude and enter them into your hand-held GPS
735 unit and have that compute a track to the landing location.
737 Both TeleMini and TeleMetrum will continue to transmit RDF
738 tones after landing, allowing you to locate the rocket by
739 following the radio signal if necessary. You may need to get
740 away from the clutter of the flight line, or even get up on
741 a hill (or your neighbor's RV roof) to receive the RDF signal.
743 The maximum height, speed and acceleration reported
744 during the flight are displayed for your admiring observers.
745 The accuracy of these immediate values depends on the quality
746 of your radio link and how many packets were received.
747 Recovering the on-board data after flight will likely yield
748 more precise results.
750 To get more detailed information about the flight, you can
751 click on the 'Graph Flight' button which will bring up a
752 graph window for the current flight.
753 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3859448"></a>1.5. Site Map</h3></div></div></div><p>
754 When the TeleMetrum has a GPS fix, the Site Map tab will map
755 the rocket's position to make it easier for you to locate the
756 rocket, both while it is in the air, and when it has landed. The
757 rocket's state is indicated by color: white for pad, red for
758 boost, pink for fast, yellow for coast, light blue for drogue,
759 dark blue for main, and black for landed.
761 The map's scale is approximately 3m (10ft) per pixel. The map
762 can be dragged using the left mouse button. The map will attempt
763 to keep the rocket roughly centered while data is being received.
765 Images are fetched automatically via the Google Maps Static API,
766 and cached on disk for reuse. If map images cannot be downloaded,
767 the rocket's path will be traced on a dark gray background
770 You can pre-load images for your favorite launch sites
771 before you leave home; check out the 'Preload Maps' section below.
772 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3861728"></a>2. Save Flight Data</h2></div></div></div><p>
773 The altimeter records flight data to its internal flash memory.
774 TeleMetrum data is recorded at a much higher rate than the telemetry
775 system can handle, and is not subject to radio drop-outs. As
776 such, it provides a more complete and precise record of the
777 flight. The 'Save Flight Data' button allows you to read the
778 flash memory and write it to disk. As TeleMini has only a barometer, it
779 records data at the same rate as the telemetry signal, but there will be
780 no data lost due to telemetry drop-outs.
782 Clicking on the 'Save Flight Data' button brings up a list of
783 connected TeleMetrum and TeleDongle devices. If you select a
784 TeleMetrum device, the flight data will be downloaded from that
785 device directly. If you select a TeleDongle device, flight data
786 will be downloaded from an altimeter over radio link via the
787 specified TeleDongle. See the chapter on Controlling An Altimeter
788 Over The Radio Link for more information.
790 After the device has been selected, a dialog showing the
791 flight data saved in the device will be shown allowing you to
792 select which flights to download and which to delete. With
793 version 0.9 or newer firmware, you must erase flights in order
794 for the space they consume to be reused by another
795 flight. This prevents accidentally losing flight data
796 if you neglect to download data before flying again. Note that
797 if there is no more space available in the device, then no
798 data will be recorded during the next flight.
800 The file name for each flight log is computed automatically
801 from the recorded flight date, altimeter serial number and
802 flight number information.
803 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3864648"></a>3. Replay Flight</h2></div></div></div><p>
804 Select this button and you are prompted to select a flight
805 record file, either a .telem file recording telemetry data or a
806 .eeprom file containing flight data saved from the altimeter
809 Once a flight record is selected, the flight monitor interface
810 is displayed and the flight is re-enacted in real time. Check
811 the Monitor Flight chapter above to learn how this window operates.
812 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3865896"></a>4. Graph Data</h2></div></div></div><p>
813 Select this button and you are prompted to select a flight
814 record file, either a .telem file recording telemetry data or a
815 .eeprom file containing flight data saved from
818 Once a flight record is selected, a window with four tabs is
819 opened. The first tab contains a graph with acceleration
820 (blue), velocity (green) and altitude (red) of the flight,
821 measured in metric units. The apogee(yellow) and main(magenta)
822 igniter voltages are also displayed; high voltages indicate
823 continuity, low voltages indicate open circuits. The second
824 tab lets you configure which data to show in the graph. The
825 third contains some basic flight statistics while the fourth
826 has a map with the ground track of the flight displayed.
828 The graph can be zoomed into a particular area by clicking and
829 dragging down and to the right. Once zoomed, the graph can be
830 reset by clicking and dragging up and to the left. Holding down
831 control and clicking and dragging allows the graph to be panned.
832 The right mouse button causes a pop-up menu to be displayed, giving
833 you the option save or print the plot.
835 Note that telemetry files will generally produce poor graphs
836 due to the lower sampling rate and missed telemetry packets.
837 Use saved flight data in .eeprom files for graphing where possible.
838 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3869184"></a>5. Export Data</h2></div></div></div><p>
839 This tool takes the raw data files and makes them available for
840 external analysis. When you select this button, you are prompted to
842 data file (either .eeprom or .telem will do, remember that
843 .eeprom files contain higher resolution and more continuous
844 data). Next, a second dialog appears which is used to select
845 where to write the resulting file. It has a selector to choose
846 between CSV and KML file formats.
847 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3870192"></a>5.1. Comma Separated Value Format</h3></div></div></div><p>
848 This is a text file containing the data in a form suitable for
849 import into a spreadsheet or other external data analysis
850 tool. The first few lines of the file contain the version and
851 configuration information from the altimeter, then
852 there is a single header line which labels all of the
853 fields. All of these lines start with a '#' character which
854 many tools can be configured to skip over.
856 The remaining lines of the file contain the data, with each
857 field separated by a comma and at least one space. All of
858 the sensor values are converted to standard units, with the
859 barometric data reported in both pressure, altitude and
860 height above pad units.
861 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3871768"></a>5.2. Keyhole Markup Language (for Google Earth)</h3></div></div></div><p>
862 This is the format used by Google Earth to provide an overlay
863 within that application. With this, you can use Google Earth to
864 see the whole flight path in 3D.
865 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3872600"></a>6. Configure Altimeter</h2></div></div></div><p>
866 Select this button and then select either a TeleMetrum or
867 TeleDongle Device from the list provided. Selecting a TeleDongle
868 device will use the radio link to configure a remote altimeter.
870 The first few lines of the dialog provide information about the
871 connected device, including the product name,
872 software version and hardware serial number. Below that are the
873 individual configuration entries.
875 At the bottom of the dialog, there are four buttons:
876 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
877 Save. This writes any changes to the
878 configuration parameter block in flash memory. If you don't
879 press this button, any changes you make will be lost.
880 </p></li><li class="listitem"><p>
881 Reset. This resets the dialog to the most recently saved values,
882 erasing any changes you have made.
883 </p></li><li class="listitem"><p>
884 Reboot. This reboots the device. Use this to
885 switch from idle to pad mode by rebooting once the rocket is
886 oriented for flight, or to confirm changes you think you saved
888 </p></li><li class="listitem"><p>
889 Close. This closes the dialog. Any unsaved changes will be
891 </p></li></ul></div><p>
892 The rest of the dialog contains the parameters to be configured.
893 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3876776"></a>6.1. Main Deploy Altitude</h3></div></div></div><p>
894 This sets the altitude (above the recorded pad altitude) at
895 which the 'main' igniter will fire. The drop-down menu shows
896 some common values, but you can edit the text directly and
897 choose whatever you like. If the apogee charge fires below
898 this altitude, then the main charge will fire two seconds
899 after the apogee charge fires.
900 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3877760"></a>6.2. Apogee Delay</h3></div></div></div><p>
901 When flying redundant electronics, it's often important to
902 ensure that multiple apogee charges don't fire at precisely
903 the same time, as that can over pressurize the apogee deployment
904 bay and cause a structural failure of the air-frame. The Apogee
905 Delay parameter tells the flight computer to fire the apogee
906 charge a certain number of seconds after apogee has been
908 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3878800"></a>6.3. Radio Frequency</h3></div></div></div><p>
909 This configures which of the configured frequencies to use for both
910 telemetry and packet command mode. Note that if you set this
911 value via packet command mode, you will have to reconfigure
912 the TeleDongle frequency before you will be able to use packet
914 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3879712"></a>6.4. Radio Calibration</h3></div></div></div><p>
915 The radios in every Altus Metrum device are calibrated at the
916 factory to ensure that they transmit and receive on the
917 specified frequency. If you need to you can adjust the calibration
918 by changing this value. Do not do this without understanding what
919 the value means, read the appendix on calibration and/or the source
920 code for more information. To change a TeleDongle's calibration,
921 you must reprogram the unit completely.
922 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3880776"></a>6.5. Callsign</h3></div></div></div><p>
923 This sets the call sign included in each telemetry packet. Set this
924 as needed to conform to your local radio regulations.
925 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3881512"></a>6.6. Maximum Flight Log Size</h3></div></div></div><p>
926 This sets the space (in kilobytes) allocated for each flight
927 log. The available space will be divided into chunks of this
928 size. A smaller value will allow more flights to be stored,
929 a larger value will record data from longer flights.
930 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3882376"></a>6.7. Ignite Mode</h3></div></div></div><p>
931 TeleMetrum and TeleMini provide two igniter channels as they
932 were originally designed as dual-deploy flight
933 computers. This configuration parameter allows the two
934 channels to be used in different configurations.
935 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
936 Dual Deploy. This is the usual mode of operation; the
937 'apogee' channel is fired at apogee and the 'main'
938 channel at the height above ground specified by the
939 'Main Deploy Altitude' during descent.
940 </p></li><li class="listitem"><p>
941 Redundant Apogee. This fires both channels at
942 apogee, the 'apogee' channel first followed after a two second
943 delay by the 'main' channel.
944 </p></li><li class="listitem"><p>
945 Redundant Main. This fires both channels at the
946 height above ground specified by the Main Deploy
947 Altitude setting during descent. The 'apogee'
948 channel is fired first, followed after a two second
949 delay by the 'main' channel.
950 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3885216"></a>6.8. Pad Orientation</h3></div></div></div><p>
951 Because it includes an accelerometer, TeleMetrum is
952 sensitive to the orientation of the board. By default, it
953 expects the antenna end to point forward. This parameter
954 allows that default to be changed, permitting the board to
955 be mounted with the antenna pointing aft instead.
956 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
957 Antenna Up. In this mode, the antenna end of the
958 TeleMetrum board must point forward, in line with the
959 expected flight path.
960 </p></li><li class="listitem"><p>
961 Antenna Down. In this mode, the antenna end of the
962 TeleMetrum board must point aft, in line with the
963 expected flight path.
964 </p></li></ul></div></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3887440"></a>7. Configure AltosUI</h2></div></div></div><p>
965 This button presents a dialog so that you can configure the AltosUI global settings.
966 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3888064"></a>7.1. Voice Settings</h3></div></div></div><p>
967 AltosUI provides voice announcements during flight so that you
968 can keep your eyes on the sky and still get information about
969 the current flight status. However, sometimes you don't want
971 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>Enable—turns all voice announcements on and off</p></li><li class="listitem"><p>
972 Test Voice—Plays a short message allowing you to verify
973 that the audio system is working and the volume settings
975 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3890336"></a>7.2. Log Directory</h3></div></div></div><p>
976 AltosUI logs all telemetry data and saves all TeleMetrum flash
977 data to this directory. This directory is also used as the
978 staring point when selecting data files for display or export.
980 Click on the directory name to bring up a directory choosing
981 dialog, select a new directory and click 'Select Directory' to
982 change where AltosUI reads and writes data files.
983 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3891560"></a>7.3. Callsign</h3></div></div></div><p>
984 This value is transmitted in each command packet sent from
985 TeleDongle and received from an altimeter. It is not used in
986 telemetry mode, as the callsign configured in the altimeter board
987 is included in all telemetry packets. Configure this
988 with the AltosUI operators call sign as needed to comply with
989 your local radio regulations.
990 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3892528"></a>7.4. Imperial Units</h3></div></div></div><p>
991 This switches between metric units (meters) and imperial
992 units (feet and miles). This affects the display of values
993 use during flight monitoring, data graphing and all of the
994 voice announcements. It does not change the units used when
995 exporting to CSV files, those are always produced in metric units.
996 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3893432"></a>7.5. Font Size</h3></div></div></div><p>
997 Selects the set of fonts used in the flight monitor
998 window. Choose between the small, medium and large sets.
999 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3894136"></a>7.6. Serial Debug</h3></div></div></div><p>
1000 This causes all communication with a connected device to be
1001 dumped to the console from which AltosUI was started. If
1002 you've started it from an icon or menu entry, the output
1003 will simply be discarded. This mode can be useful to debug
1004 various serial communication issues.
1005 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3895048"></a>7.7. Manage Frequencies</h3></div></div></div><p>
1006 This brings up a dialog where you can configure the set of
1007 frequencies shown in the various frequency menus. You can
1008 add as many as you like, or even reconfigure the default
1009 set. Changing this list does not affect the frequency
1010 settings of any devices, it only changes the set of
1011 frequencies shown in the menus.
1012 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3896032"></a>8. Configure Groundstation</h2></div></div></div><p>
1013 Select this button and then select a TeleDongle Device from the list provided.
1015 The first few lines of the dialog provide information about the
1016 connected device, including the product name,
1017 software version and hardware serial number. Below that are the
1018 individual configuration entries.
1020 Note that the TeleDongle itself doesn't save any configuration
1021 data, the settings here are recorded on the local machine in
1022 the Java preferences database. Moving the TeleDongle to
1023 another machine, or using a different user account on the same
1024 machine will cause settings made here to have no effect.
1026 At the bottom of the dialog, there are three buttons:
1027 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
1028 Save. This writes any changes to the
1029 local Java preferences file. If you don't
1030 press this button, any changes you make will be lost.
1031 </p></li><li class="listitem"><p>
1032 Reset. This resets the dialog to the most recently saved values,
1033 erasing any changes you have made.
1034 </p></li><li class="listitem"><p>
1035 Close. This closes the dialog. Any unsaved changes will be
1037 </p></li></ul></div><p>
1038 The rest of the dialog contains the parameters to be configured.
1039 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3899952"></a>8.1. Frequency</h3></div></div></div><p>
1040 This configures the frequency to use for both telemetry and
1041 packet command mode. Set this before starting any operation
1042 involving packet command mode so that it will use the right
1043 frequency. Telemetry monitoring mode also provides a menu to
1044 change the frequency, and that menu also sets the same Java
1045 preference value used here.
1046 </p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3900936"></a>8.2. Radio Calibration</h3></div></div></div><p>
1047 The radios in every Altus Metrum device are calibrated at the
1048 factory to ensure that they transmit and receive on the
1049 specified frequency. To change a TeleDongle's calibration,
1050 you must reprogram the unit completely, so this entry simply
1051 shows the current value and doesn't allow any changes.
1052 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3901928"></a>9. Flash Image</h2></div></div></div><p>
1053 This reprograms any Altus Metrum device by using a TeleMetrum
1054 or TeleDongle as a programming dongle. Please read the
1055 directions for flashing devices in the Updating Device
1056 Firmware chapter below.
1058 Once you have the programmer and target devices connected,
1059 push the 'Flash Image' button. That will present a dialog box
1060 listing all of the connected devices. Carefully select the
1061 programmer device, not the device to be programmed.
1063 Next, select the image to flash to the device. These are named
1064 with the product name and firmware version. The file selector
1065 will start in the directory containing the firmware included
1066 with the AltosUI package. Navigate to the directory containing
1067 the desired firmware if it isn't there.
1069 Next, a small dialog containing the device serial number and
1070 RF calibration values should appear. If these values are
1071 incorrect (possibly due to a corrupted image in the device),
1072 enter the correct values here.
1074 Finally, a dialog containing a progress bar will follow the
1075 programming process.
1077 When programming is complete, the target device will
1078 reboot. Note that if the target device is connected via USB, you
1079 will have to unplug it and then plug it back in for the USB
1080 connection to reset so that you can communicate with the device
1082 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3905000"></a>10. Fire Igniter</h2></div></div></div><p>
1083 This activates the igniter circuits in TeleMetrum to help test
1084 recovery systems deployment. Because this command can operate
1085 over the Packet Command Link, you can prepare the rocket as
1086 for flight and then test the recovery system without needing
1087 to snake wires inside the air-frame.
1089 Selecting the 'Fire Igniter' button brings up the usual device
1090 selection dialog. Pick the desired TeleDongle or TeleMetrum
1091 device. This brings up another window which shows the current
1092 continuity test status for both apogee and main charges.
1094 Next, select the desired igniter to fire. This will enable the
1097 Select the 'Arm' button. This enables the 'Fire' button. The
1098 word 'Arm' is replaced by a countdown timer indicating that
1099 you have 10 seconds to press the 'Fire' button or the system
1100 will deactivate, at which point you start over again at
1101 selecting the desired igniter.
1102 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3907104"></a>11. Scan Channels</h2></div></div></div><p>
1103 This listens for telemetry packets on all of the configured
1104 frequencies, displaying information about each device it
1105 receives a packet from. You can select which of the three
1106 telemetry formats should be tried; by default, it only listens
1107 for the standard telemetry packets used in v1.0 and later
1109 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3908008"></a>12. Load Maps</h2></div></div></div><p>
1110 Before heading out to a new launch site, you can use this to
1111 load satellite images in case you don't have internet
1112 connectivity at the site. This loads a fairly large area
1113 around the launch site, which should cover any flight you're likely to make.
1115 There's a drop-down menu of launch sites we know about; if
1116 your favorites aren't there, please let us know the lat/lon
1117 and name of the site. The contents of this list are actually
1118 downloaded at run-time, so as new sites are sent in, they'll
1119 get automatically added to this list.
1121 If the launch site isn't in the list, you can manually enter the lat/lon values
1123 Clicking the 'Load Map' button will fetch images from Google
1124 Maps; note that Google limits how many images you can fetch at
1125 once, so if you load more than one launch site, you may get
1126 some gray areas in the map which indicate that Google is tired
1127 of sending data to you. Try again later.
1128 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3910136"></a>13. Monitor Idle</h2></div></div></div><p>
1129 This brings up a dialog similar to the Monitor Flight UI,
1130 except it works with the altimeter in "idle" mode by sending
1131 query commands to discover the current state rather than
1132 listening for telemetry packets.
1133 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp3911008"></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="#idp3912688">1. Installing AltosDroid</a></span></dt><dt><span class="section"><a href="#idp3913648">2. Connecting to TeleBT</a></span></dt><dt><span class="section"><a href="#idp3914864">3. Configuring AltosDroid</a></span></dt><dt><span class="section"><a href="#idp3915736">4. Altos Droid Flight Monitoring</a></span></dt><dd><dl><dt><span class="section"><a href="#idp3916536">4.1. Pad</a></span></dt></dl></dd><dt><span class="section"><a href="#idp3922504">5. Downloading Flight Logs</a></span></dt></dl></div><p>
1134 AltosDroid provides the same flight monitoring capabilities as
1135 AltosUI, but runs on Android devices and is designed to connect
1136 to a TeleBT receiver over Bluetooth™. Altos Droid monitors
1137 telemetry data, logging it to internal storage in the Android
1138 device, and presents that data in a UI the same way the 'Monitor
1139 Flight' window does in AltosUI.
1141 This manual will explain how to configure AltosDroid, connect
1142 to TeleBT, operate the flight monitoring interface and describe
1143 what the displayed data means.
1144 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3912688"></a>1. Installing AltosDroid</h2></div></div></div><p>
1145 AltosDroid is included in the Google Play store. To install
1146 it on your Android device, open open the Google Play Store
1147 application and search for "altosdroid". Make sure you don't
1148 have a space between "altos" and "droid" or you probably won't
1149 find what you want. That should bring you to the right page
1150 from which you can download and install the application.
1151 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3913648"></a>2. Connecting to TeleBT</h2></div></div></div><p>
1152 Press the Android 'Menu' button or soft-key to see the
1153 configuration options available. Select the 'Connect a device'
1154 option and then the 'Scan for devices' entry at the bottom to
1155 look for your TeleBT device. Select your device, and when it
1156 asks for the code, enter '1234'.
1158 Subsequent connections will not require you to enter that
1159 code, and your 'paired' device will appear in the list without
1161 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3914864"></a>3. Configuring AltosDroid</h2></div></div></div><p>
1162 The only configuration option available for AltosDroid is
1163 which frequency to listen on. Press the Android 'Menu' button
1164 or soft-key and pick the 'Select radio frequency' entry. That
1165 brings up a menu of pre-set radio frequencies; pick the one
1166 which matches your altimeter.
1167 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3915736"></a>4. Altos Droid Flight Monitoring</h2></div></div></div><p>
1168 Altos Droid is designed to mimic the AltosUI flight monitoring
1169 display, providing separate tabs for each stage of your rocket
1170 flight along with a tab containing a map of the local area
1171 with icons marking the current location of the altimeter and
1173 </p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp3916536"></a>4.1. Pad</h3></div></div></div><p>
1174 The 'Launch Pad' tab shows information used to decide when the
1175 rocket is ready for flight. The first elements include red/green
1176 indicators, if any of these is red, you'll want to evaluate
1177 whether the rocket is ready to launch:
1178 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
1179 Battery Voltage. This indicates whether the Li-Po battery
1180 powering the TeleMetrum has sufficient charge to last for
1181 the duration of the flight. A value of more than
1182 3.7V is required for a 'GO' status.
1183 </p></li><li class="listitem"><p>
1184 Apogee Igniter Voltage. This indicates whether the apogee
1185 igniter has continuity. If the igniter has a low
1186 resistance, then the voltage measured here will be close
1187 to the Li-Po battery voltage. A value greater than 3.2V is
1188 required for a 'GO' status.
1189 </p></li><li class="listitem"><p>
1190 Main Igniter Voltage. This indicates whether the main
1191 igniter has continuity. If the igniter has a low
1192 resistance, then the voltage measured here will be close
1193 to the Li-Po battery voltage. A value greater than 3.2V is
1194 required for a 'GO' status.
1195 </p></li><li class="listitem"><p>
1196 On-board Data Logging. This indicates whether there is
1197 space remaining on-board to store flight data for the
1198 upcoming flight. If you've downloaded data, but failed
1199 to erase flights, there may not be any space
1200 left. TeleMetrum can store multiple flights, depending
1201 on the configured maximum flight log size. TeleMini
1202 stores only a single flight, so it will need to be
1203 downloaded and erased after each flight to capture
1204 data. This only affects on-board flight logging; the
1205 altimeter will still transmit telemetry and fire
1206 ejection charges at the proper times.
1207 </p></li><li class="listitem"><p>
1208 GPS Locked. For a TeleMetrum device, this indicates whether the GPS receiver is
1209 currently able to compute position information. GPS requires
1210 at least 4 satellites to compute an accurate position.
1211 </p></li><li class="listitem"><p>
1212 GPS Ready. For a TeleMetrum device, this indicates whether GPS has reported at least
1213 10 consecutive positions without losing lock. This ensures
1214 that the GPS receiver has reliable reception from the
1216 </p></li></ul></div><p>
1218 The Launchpad tab also shows the computed launch pad position
1219 and altitude, averaging many reported positions to improve the
1220 accuracy of the fix.
1222 </p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3922504"></a>5. Downloading Flight Logs</h2></div></div></div><p>
1223 Altos Droid always saves every bit of telemetry data it
1224 receives. To download that to a computer for use with AltosUI,
1225 simply remove the SD card from your Android device, or connect
1226 your device to your computer's USB port and browse the files
1227 on that device. You will find '.telem' files in the TeleMetrum
1228 directory that will work with AltosUI directly.
1229 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp3923520"></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="#idp3923840">1. Being Legal</a></span></dt><dt><span class="section"><a href="#idp3924800">2. In the Rocket</a></span></dt><dt><span class="section"><a href="#idp3926904">3. On the Ground</a></span></dt><dt><span class="section"><a href="#idp3934536">4. Data Analysis</a></span></dt><dt><span class="section"><a href="#idp3936288">5. Future Plans</a></span></dt></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3923840"></a>1. Being Legal</h2></div></div></div><p>
1230 First off, in the US, you need an <a class="ulink" href="http://www.altusmetrum.org/Radio/" target="_top">amateur radio license</a> or
1231 other authorization to legally operate the radio transmitters that are part
1233 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3924800"></a>2. In the Rocket</h2></div></div></div><p>
1234 In the rocket itself, you just need a <a class="ulink" href="http://www.altusmetrum.org/TeleMetrum/" target="_top">TeleMetrum</a> or
1235 <a class="ulink" href="http://www.altusmetrum.org/TeleMini/" target="_top">TeleMini</a> board and
1236 a single-cell, 3.7 volt nominal Li-Po rechargeable battery. An
1237 850mAh battery weighs less than a 9V alkaline battery, and will
1238 run a TeleMetrum for hours.
1239 A 110mAh battery weighs less than a triple A battery and will run a TeleMetrum for
1240 a few hours, or a TeleMini for much (much) longer.
1242 By default, we ship the altimeters with a simple wire antenna. If your
1243 electronics bay or the air-frame it resides within is made of carbon fiber,
1244 which is opaque to RF signals, you may choose to have an SMA connector
1245 installed so that you can run a coaxial cable to an antenna mounted
1246 elsewhere in the rocket.
1247 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3926904"></a>3. On the Ground</h2></div></div></div><p>
1248 To receive the data stream from the rocket, you need an antenna and short
1249 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
1250 adapter instead of feedline between the antenna feedpoint and
1251 TeleDongle, as this will give you the best performance. The
1252 TeleDongle in turn plugs directly into the USB port on a notebook
1253 computer. Because TeleDongle looks like a simple serial port, your computer
1254 does not require special device drivers... just plug it in.
1256 The GUI tool, AltosUI, is written in Java and runs across
1257 Linux, Mac OS and Windows. There's also a suite of C tools
1258 for Linux which can perform most of the same tasks.
1260 After the flight, you can use the radio link to extract the more detailed data
1261 logged in either TeleMetrum or TeleMini devices, or you can use a mini USB cable to plug into the
1262 TeleMetrum board directly. Pulling out the data without having to open up
1263 the rocket is pretty cool! A USB cable is also how you charge the Li-Po
1264 battery, so you'll want one of those anyway... the same cable used by lots
1265 of digital cameras and other modern electronic stuff will work fine.
1267 If your TeleMetrum-equipped rocket lands out of sight, you may enjoy having a hand-held GPS
1268 receiver, so that you can put in a way-point for the last reported rocket
1269 position before touch-down. This makes looking for your rocket a lot like
1270 Geo-Caching... just go to the way-point and look around starting from there.
1272 You may also enjoy having a ham radio "HT" that covers the 70cm band... you
1273 can use that with your antenna to direction-find the rocket on the ground
1274 the same way you can use a Walston or Beeline tracker. This can be handy
1275 if the rocket is hiding in sage brush or a tree, or if the last GPS position
1276 doesn't get you close enough because the rocket dropped into a canyon, or
1277 the wind is blowing it across a dry lake bed, or something like that... Keith
1278 and Bdale both currently own and use the Yaesu VX-7R at launches.
1280 So, to recap, on the ground the hardware you'll need includes:
1281 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem">
1282 an antenna and feed-line or adapter
1283 </li><li class="listitem">
1285 </li><li class="listitem">
1287 </li><li class="listitem">
1288 optionally, a hand-held GPS receiver
1289 </li><li class="listitem">
1290 optionally, an HT or receiver covering 435 MHz
1293 The best hand-held commercial directional antennas we've found for radio
1294 direction finding rockets are from
1295 <a class="ulink" href="http://www.arrowantennas.com/" target="_top">
1298 The 440-3 and 440-5 are both good choices for finding a
1299 TeleMetrum- or TeleMini- equipped rocket when used with a suitable
1300 70cm HT. TeleDongle and an SMA to BNC adapter fit perfectly
1301 between the driven element and reflector of Arrow antennas.
1302 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3934536"></a>4. Data Analysis</h2></div></div></div><p>
1303 Our software makes it easy to log the data from each flight, both the
1304 telemetry received during the flight itself, and the more
1305 complete data log recorded in the flash memory on the altimeter
1306 board. Once this data is on your computer, our post-flight tools make it
1307 easy to quickly get to the numbers everyone wants, like apogee altitude,
1308 max acceleration, and max velocity. You can also generate and view a
1309 standard set of plots showing the altitude, acceleration, and
1310 velocity of the rocket during flight. And you can even export a TeleMetrum data file
1311 usable with Google Maps and Google Earth for visualizing the flight path
1312 in two or three dimensions!
1314 Our ultimate goal is to emit a set of files for each flight that can be
1315 published as a web page per flight, or just viewed on your local disk with
1317 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3936288"></a>5. Future Plans</h2></div></div></div><p>
1318 In the future, we intend to offer "companion boards" for the rocket
1319 that will plug in to TeleMetrum to collect additional data, provide
1320 more pyro channels, and so forth.
1322 Also under design is a new flight computer with more sensors, more
1323 pyro channels, and a more powerful radio system designed for use
1324 in multi-stage, complex, and extreme altitude projects.
1326 We are also working on alternatives to TeleDongle. One is a
1327 a stand-alone, hand-held ground terminal that will allow monitoring
1328 the rocket's status, collecting data during flight, and logging data
1329 after flight without the need for a notebook computer on the
1330 flight line. Particularly since it is so difficult to read most
1331 notebook screens in direct sunlight, we think this will be a great
1332 thing to have. We are also working on a TeleDongle variant with
1333 Bluetooth that will work with Android phones and tablets.
1335 Because all of our work is open, both the hardware designs and the
1336 software, if you have some great idea for an addition to the current
1337 Altus Metrum family, feel free to dive in and help! Or let us know
1338 what you'd like to see that we aren't already working on, and maybe
1339 we'll get excited about it too...
1342 <a class="ulink" href="http://altusmetrum.org/" target="_top">web site</a> for more news
1343 and information as our family of products evolves!
1344 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp3939448"></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="#idp3940432">1. Mounting the Altimeter</a></span></dt><dt><span class="section"><a href="#idp3942768">2. Dealing with the Antenna</a></span></dt><dt><span class="section"><a href="#idp3946752">3. Preserving GPS Reception</a></span></dt><dt><span class="section"><a href="#idp3949136">4. Radio Frequency Interference</a></span></dt><dt><span class="section"><a href="#idp3953208">5. The Barometric Sensor</a></span></dt><dt><span class="section"><a href="#idp3955048">6. Ground Testing</a></span></dt></dl></div><p>
1345 Building high-power rockets that fly safely is hard enough. Mix
1346 in some sophisticated electronics and a bunch of radio energy
1347 and oftentimes you find few perfect solutions. This chapter
1348 contains some suggestions about how to install Altus Metrum
1349 products into the rocket air-frame, including how to safely and
1350 reliably mix a variety of electronics into the same air-frame.
1351 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3940432"></a>1. Mounting the Altimeter</h2></div></div></div><p>
1352 The first consideration is to ensure that the altimeter is
1353 securely fastened to the air-frame. For TeleMetrum, we use
1354 nylon standoffs and nylon screws; they're good to at least 50G
1355 and cannot cause any electrical issues on the board. For
1356 TeleMini, we usually cut small pieces of 1/16" balsa to fit
1357 under the screw holes, and then take 2x56 nylon screws and
1358 screw them through the TeleMini mounting holes, through the
1359 balsa and into the underlying material.
1360 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem">
1361 Make sure TeleMetrum is aligned precisely along the axis of
1362 acceleration so that the accelerometer can accurately
1363 capture data during the flight.
1364 </li><li class="listitem">
1365 Watch for any metal touching components on the
1366 board. Shorting out connections on the bottom of the board
1367 can cause the altimeter to fail during flight.
1368 </li></ol></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3942768"></a>2. Dealing with the Antenna</h2></div></div></div><p>
1369 The antenna supplied is just a piece of solid, insulated,
1370 wire. If it gets damaged or broken, it can be easily
1371 replaced. It should be kept straight and not cut; bending or
1372 cutting it will change the resonant frequency and/or
1373 impedance, making it a less efficient radiator and thus
1374 reducing the range of the telemetry signal.
1376 Keeping metal away from the antenna will provide better range
1377 and a more even radiation pattern. In most rockets, it's not
1378 entirely possible to isolate the antenna from metal
1379 components; there are often bolts, all-thread and wires from other
1380 electronics to contend with. Just be aware that the more stuff
1381 like this around the antenna, the lower the range.
1383 Make sure the antenna is not inside a tube made or covered
1384 with conducting material. Carbon fiber is the most common
1385 culprit here -- CF is a good conductor and will effectively
1386 shield the antenna, dramatically reducing signal strength and
1387 range. Metallic flake paint is another effective shielding
1388 material which is to be avoided around any antennas.
1390 If the ebay is large enough, it can be convenient to simply
1391 mount the altimeter at one end and stretch the antenna out
1392 inside. Taping the antenna to the sled can keep it straight
1393 under acceleration. If there are metal rods, keep the
1394 antenna as far away as possible.
1396 For a shorter ebay, it's quite practical to have the antenna
1397 run through a bulkhead and into an adjacent bay. Drill a small
1398 hole in the bulkhead, pass the antenna wire through it and
1399 then seal it up with glue or clay. We've also used acrylic
1400 tubing to create a cavity for the antenna wire. This works a
1401 bit better in that the antenna is known to stay straight and
1402 not get folded by recovery components in the bay. Angle the
1403 tubing towards the side wall of the rocket and it ends up
1404 consuming very little space.
1406 If you need to place the antenna at a distance from the
1407 altimeter, you can replace the antenna with an edge-mounted
1408 SMA connector, and then run 50Ω coax from the board to the
1409 antenna. Building a remote antenna is beyond the scope of this
1411 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3946752"></a>3. Preserving GPS Reception</h2></div></div></div><p>
1412 The GPS antenna and receiver in TeleMetrum are highly
1413 sensitive and normally have no trouble tracking enough
1414 satellites to provide accurate position information for
1415 recovering the rocket. However, there are many ways to
1416 attenuate the GPS signal.
1417 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem">
1418 Conductive tubing or coatings. Carbon fiber and metal
1419 tubing, or metallic paint will all dramatically attenuate the
1420 GPS signal. We've never heard of anyone successfully
1421 receiving GPS from inside these materials.
1422 </li><li class="listitem">
1423 Metal components near the GPS patch antenna. These will
1424 de-tune the patch antenna, changing the resonant frequency
1425 away from the L1 carrier and reduce the effectiveness of the
1426 antenna. You can place as much stuff as you like beneath the
1427 antenna as that's covered with a ground plane. But, keep
1428 wires and metal out from above the patch antenna.
1430 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3949136"></a>4. Radio Frequency Interference</h2></div></div></div><p>
1431 Any altimeter will generate RFI; the digital circuits use
1432 high-frequency clocks that spray radio interference across a
1433 wide band. Altus Metrum altimeters generate intentional radio
1434 signals as well, increasing the amount of RF energy around the board.
1436 Rocketry altimeters also use precise sensors measuring air
1437 pressure and acceleration. Tiny changes in voltage can cause
1438 these sensor readings to vary by a huge amount. When the
1439 sensors start mis-reporting data, the altimeter can either
1440 fire the igniters at the wrong time, or not fire them at all.
1442 Voltages are induced when radio frequency energy is
1443 transmitted from one circuit to another. Here are things that
1444 influence the induced voltage and current:
1445 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
1446 Keep wires from different circuits apart. Moving circuits
1447 further apart will reduce RFI.
1448 </li><li class="listitem">
1449 Avoid parallel wires from different circuits. The longer two
1450 wires run parallel to one another, the larger the amount of
1451 transferred energy. Cross wires at right angles to reduce
1453 </li><li class="listitem">
1454 Twist wires from the same circuits. Two wires the same
1455 distance from the transmitter will get the same amount of
1456 induced energy which will then cancel out. Any time you have
1457 a wire pair running together, twist the pair together to
1458 even out distances and reduce RFI. For altimeters, this
1459 includes battery leads, switch hookups and igniter
1461 </li><li class="listitem">
1462 Avoid resonant lengths. Know what frequencies are present
1463 in the environment and avoid having wire lengths near a
1464 natural resonant length. Altusmetrum products transmit on the
1465 70cm amateur band, so you should avoid lengths that are a
1466 simple ratio of that length; essentially any multiple of 1/4
1467 of the wavelength (17.5cm).
1468 </li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3953208"></a>5. The Barometric Sensor</h2></div></div></div><p>
1469 Altusmetrum altimeters measure altitude with a barometric
1470 sensor, essentially measuring the amount of air above the
1471 rocket to figure out how high it is. A large number of
1472 measurements are taken as the altimeter initializes itself to
1473 figure out the pad altitude. Subsequent measurements are then
1474 used to compute the height above the pad.
1476 To accurately measure atmospheric pressure, the ebay
1477 containing the altimeter must be vented outside the
1478 air-frame. The vent must be placed in a region of linear
1479 airflow, have smooth edges, and away from areas of increasing or
1480 decreasing pressure.
1482 The barometric sensor in the altimeter is quite sensitive to
1483 chemical damage from the products of APCP or BP combustion, so
1484 make sure the ebay is carefully sealed from any compartment
1485 which contains ejection charges or motors.
1486 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3955048"></a>6. Ground Testing</h2></div></div></div><p>
1487 The most important aspect of any installation is careful
1488 ground testing. Bringing an air-frame up to the LCO table which
1489 hasn't been ground tested can lead to delays or ejection
1490 charges firing on the pad, or, even worse, a recovery system
1493 Do a 'full systems' test that includes wiring up all igniters
1494 without any BP and turning on all of the electronics in flight
1495 mode. This will catch any mistakes in wiring and any residual
1496 RFI issues that might accidentally fire igniters at the wrong
1497 time. Let the air-frame sit for several minutes, checking for
1498 adequate telemetry signal strength and GPS lock. If any igniters
1499 fire unexpectedly, find and resolve the issue before loading any
1502 Ground test the ejection charges. Prepare the rocket for
1503 flight, loading ejection charges and igniters. Completely
1504 assemble the air-frame and then use the 'Fire Igniters'
1505 interface through a TeleDongle to command each charge to
1506 fire. Make sure the charge is sufficient to robustly separate
1507 the air-frame and deploy the recovery system.
1508 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp3957184"></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="#idp3959184">1. Updating TeleMetrum Firmware</a></span></dt><dt><span class="section"><a href="#idp3964528">2. Updating TeleMini Firmware</a></span></dt><dt><span class="section"><a href="#idp3969944">3. Updating TeleDongle Firmware</a></span></dt></dl></div><p>
1509 The big concept to understand is that you have to use a
1510 TeleDongle as a programmer to update a TeleMetrum or TeleMini,
1511 and a TeleMetrum or other TeleDongle to program the TeleDongle
1512 Due to limited memory resources in the cc1111, we don't support
1513 programming directly over USB.
1515 You may wish to begin by ensuring you have current firmware images.
1516 These are distributed as part of the AltOS software bundle that
1517 also includes the AltosUI ground station program. Newer ground
1518 station versions typically work fine with older firmware versions,
1519 so you don't need to update your devices just to try out new
1520 software features. You can always download the most recent
1521 version from <a class="ulink" href="http://www.altusmetrum.org/AltOS/" target="_top">http://www.altusmetrum.org/AltOS/</a>.
1523 We recommend updating the altimeter first, before updating TeleDongle.
1524 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3959184"></a>1. Updating TeleMetrum Firmware</h2></div></div></div><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem">
1525 Find the 'programming cable' that you got as part of the starter
1526 kit, that has a red 8-pin MicroMaTch connector on one end and a
1527 red 4-pin MicroMaTch connector on the other end.
1528 </li><li class="listitem">
1529 Take the 2 screws out of the TeleDongle case to get access
1530 to the circuit board.
1531 </li><li class="listitem">
1532 Plug the 8-pin end of the programming cable to the
1533 matching connector on the TeleDongle, and the 4-pin end to the
1534 matching connector on the TeleMetrum.
1535 Note that each MicroMaTch connector has an alignment pin that
1536 goes through a hole in the PC board when you have the cable
1538 </li><li class="listitem">
1539 Attach a battery to the TeleMetrum board.
1540 </li><li class="listitem">
1541 Plug the TeleDongle into your computer's USB port, and power
1543 </li><li class="listitem">
1544 Run AltosUI, and select 'Flash Image' from the File menu.
1545 </li><li class="listitem">
1546 Pick the TeleDongle device from the list, identifying it as the
1548 </li><li class="listitem">
1549 Select the image you want put on the TeleMetrum, which should have a
1550 name in the form telemetrum-v1.2-1.0.0.ihx. It should be visible
1551 in the default directory, if not you may have to poke around
1552 your system to find it.
1553 </li><li class="listitem">
1554 Make sure the configuration parameters are reasonable
1555 looking. If the serial number and/or RF configuration
1556 values aren't right, you'll need to change them.
1557 </li><li class="listitem">
1558 Hit the 'OK' button and the software should proceed to flash
1559 the TeleMetrum with new firmware, showing a progress bar.
1560 </li><li class="listitem">
1561 Confirm that the TeleMetrum board seems to have updated OK, which you
1562 can do by plugging in to it over USB and using a terminal program
1563 to connect to the board and issue the 'v' command to check
1565 </li><li class="listitem">
1566 If something goes wrong, give it another try.
1567 </li></ol></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3964528"></a>2. Updating TeleMini Firmware</h2></div></div></div><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem">
1568 You'll need a special 'programming cable' to reprogram the
1569 TeleMini. It's available on the Altus Metrum web store, or
1570 you can make your own using an 8-pin MicroMaTch connector on
1571 one end and a set of four pins on the other.
1572 </li><li class="listitem">
1573 Take the 2 screws out of the TeleDongle case to get access
1574 to the circuit board.
1575 </li><li class="listitem">
1576 Plug the 8-pin end of the programming cable to the matching
1577 connector on the TeleDongle, and the 4-pins into the holes
1578 in the TeleMini circuit board. Note that the MicroMaTch
1579 connector has an alignment pin that goes through a hole in
1580 the PC board when you have the cable oriented correctly, and
1581 that pin 1 on the TeleMini board is marked with a square pad
1582 while the other pins have round pads.
1583 </li><li class="listitem">
1584 Attach a battery to the TeleMini board.
1585 </li><li class="listitem">
1586 Plug the TeleDongle into your computer's USB port, and power
1588 </li><li class="listitem">
1589 Run AltosUI, and select 'Flash Image' from the File menu.
1590 </li><li class="listitem">
1591 Pick the TeleDongle device from the list, identifying it as the
1593 </li><li class="listitem">
1594 Select the image you want put on the TeleMini, which should have a
1595 name in the form telemini-v1.0-1.0.0.ihx. It should be visible
1596 in the default directory, if not you may have to poke around
1597 your system to find it.
1598 </li><li class="listitem">
1599 Make sure the configuration parameters are reasonable
1600 looking. If the serial number and/or RF configuration
1601 values aren't right, you'll need to change them.
1602 </li><li class="listitem">
1603 Hit the 'OK' button and the software should proceed to flash
1604 the TeleMini with new firmware, showing a progress bar.
1605 </li><li class="listitem">
1606 Confirm that the TeleMini board seems to have updated OK, which you
1607 can do by configuring it over the radio link through the TeleDongle, or
1608 letting it come up in "flight" mode and listening for telemetry.
1609 </li><li class="listitem">
1610 If something goes wrong, give it another try.
1611 </li></ol></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3969944"></a>3. Updating TeleDongle Firmware</h2></div></div></div><p>
1612 Updating TeleDongle's firmware is just like updating TeleMetrum or TeleMini
1613 firmware, but you use either a TeleMetrum or another TeleDongle as the programmer.
1614 </p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem">
1615 Find the 'programming cable' that you got as part of the starter
1616 kit, that has a red 8-pin MicroMaTch connector on one end and a
1617 red 4-pin MicroMaTch connector on the other end.
1618 </li><li class="listitem">
1619 Find the USB cable that you got as part of the starter kit, and
1620 plug the "mini" end in to the mating connector on TeleMetrum or TeleDongle.
1621 </li><li class="listitem">
1622 Take the 2 screws out of the TeleDongle case to get access
1623 to the circuit board.
1624 </li><li class="listitem">
1625 Plug the 8-pin end of the programming cable to the
1626 matching connector on the programmer, and the 4-pin end to the
1627 matching connector on the TeleDongle.
1628 Note that each MicroMaTch connector has an alignment pin that
1629 goes through a hole in the PC board when you have the cable
1631 </li><li class="listitem">
1632 Attach a battery to the TeleMetrum board if you're using one.
1633 </li><li class="listitem">
1634 Plug both the programmer and the TeleDongle into your computer's USB
1635 ports, and power up the programmer.
1636 </li><li class="listitem">
1637 Run AltosUI, and select 'Flash Image' from the File menu.
1638 </li><li class="listitem">
1639 Pick the programmer device from the list, identifying it as the
1641 </li><li class="listitem">
1642 Select the image you want put on the TeleDongle, which should have a
1643 name in the form teledongle-v0.2-1.0.0.ihx. It should be visible
1644 in the default directory, if not you may have to poke around
1645 your system to find it.
1646 </li><li class="listitem">
1647 Make sure the configuration parameters are reasonable
1648 looking. If the serial number and/or RF configuration
1649 values aren't right, you'll need to change them. The TeleDongle
1650 serial number is on the "bottom" of the circuit board, and can
1651 usually be read through the translucent blue plastic case without
1652 needing to remove the board from the case.
1653 </li><li class="listitem">
1654 Hit the 'OK' button and the software should proceed to flash
1655 the TeleDongle with new firmware, showing a progress bar.
1656 </li><li class="listitem">
1657 Confirm that the TeleDongle board seems to have updated OK, which you
1658 can do by plugging in to it over USB and using a terminal program
1659 to connect to the board and issue the 'v' command to check
1660 the version, etc. Once you're happy, remove the programming cable
1661 and put the cover back on the TeleDongle.
1662 </li><li class="listitem">
1663 If something goes wrong, give it another try.
1665 Be careful removing the programming cable from the locking 8-pin
1666 connector on TeleMetrum. You'll need a fingernail or perhaps a thin
1667 screwdriver or knife blade to gently pry the locking ears out
1668 slightly to extract the connector. We used a locking connector on
1669 TeleMetrum to help ensure that the cabling to companion boards
1670 used in a rocket don't ever come loose accidentally in flight.
1671 </p></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp3977040"></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="#idp3977360">1. TeleMetrum Specifications</a></span></dt><dt><span class="section"><a href="#idp3983088">2. TeleMini Specifications</a></span></dt></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3977360"></a>1. TeleMetrum Specifications</h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
1672 Recording altimeter for model rocketry.
1673 </p></li><li class="listitem"><p>
1674 Supports dual deployment (can fire 2 ejection charges).
1675 </p></li><li class="listitem"><p>
1676 70cm ham-band transceiver for telemetry down-link.
1677 </p></li><li class="listitem"><p>
1678 Barometric pressure sensor good to 45k feet MSL.
1679 </p></li><li class="listitem"><p>
1680 1-axis high-g accelerometer for motor characterization, capable of
1681 +/- 50g using default part.
1682 </p></li><li class="listitem"><p>
1683 On-board, integrated GPS receiver with 5Hz update rate capability.
1684 </p></li><li class="listitem"><p>
1685 On-board 1 megabyte non-volatile memory for flight data storage.
1686 </p></li><li class="listitem"><p>
1687 USB interface for battery charging, configuration, and data recovery.
1688 </p></li><li class="listitem"><p>
1689 Fully integrated support for Li-Po rechargeable batteries.
1690 </p></li><li class="listitem"><p>
1691 Uses Li-Po to fire e-matches, can be modified to support
1692 optional separate pyro battery if needed.
1693 </p></li><li class="listitem"><p>
1694 2.75 x 1 inch board designed to fit inside 29mm air-frame coupler tube.
1695 </p></li></ul></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp3983088"></a>2. TeleMini Specifications</h2></div></div></div><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>
1696 Recording altimeter for model rocketry.
1697 </p></li><li class="listitem"><p>
1698 Supports dual deployment (can fire 2 ejection charges).
1699 </p></li><li class="listitem"><p>
1700 70cm ham-band transceiver for telemetry down-link.
1701 </p></li><li class="listitem"><p>
1702 Barometric pressure sensor good to 45k feet MSL.
1703 </p></li><li class="listitem"><p>
1704 On-board 5 kilobyte non-volatile memory for flight data storage.
1705 </p></li><li class="listitem"><p>
1706 RF interface for configuration, and data recovery.
1707 </p></li><li class="listitem"><p>
1708 Support for Li-Po rechargeable batteries, using an external charger.
1709 </p></li><li class="listitem"><p>
1710 Uses Li-Po to fire e-matches, can be modified to support
1711 optional separate pyro battery if needed.
1712 </p></li><li class="listitem"><p>
1713 1.5 x .5 inch board designed to fit inside 18mm air-frame coupler tube.
1714 </p></li></ul></div></div></div><div class="chapter"><div class="titlepage"><div><div><h1 class="title"><a name="idp3987896"></a>Chapter 12. FAQ</h1></div></div></div><p>
1715 TeleMetrum seems to shut off when disconnected from the
1716 computer. Make sure the battery is adequately charged. Remember the
1717 unit will pull more power than the USB port can deliver before the
1718 GPS enters "locked" mode. The battery charges best when TeleMetrum
1721 It's impossible to stop the TeleDongle when it's in "p" mode, I have
1722 to unplug the USB cable? Make sure you have tried to "escape out" of
1723 this mode. If this doesn't work the reboot procedure for the
1724 TeleDongle *is* to simply unplug it. 'cu' however will retain it's
1725 outgoing buffer IF your "escape out" ('~~') does not work.
1726 At this point using either 'ao-view' (or possibly
1727 'cutemon') instead of 'cu' will 'clear' the issue and allow renewed
1730 The amber LED (on the TeleMetrum) lights up when both
1731 battery and USB are connected. Does this mean it's charging?
1732 Yes, the yellow LED indicates the charging at the 'regular' rate.
1733 If the led is out but the unit is still plugged into a USB port,
1734 then the battery is being charged at a 'trickle' rate.
1736 There are no "dit-dah-dah-dit" sound or lights like the manual mentions?
1737 That's the "pad" mode. Weak batteries might be the problem.
1738 It is also possible that the TeleMetrum is horizontal and the output
1739 is instead a "dit-dit" meaning 'idle'. For TeleMini, it's possible that
1740 it received a command packet which would have left it in "pad" mode.
1742 How do I save flight data?
1743 Live telemetry is written to file(s) whenever AltosUI is connected
1744 to the TeleDongle. The file area defaults to ~/TeleMetrum
1745 but is easily changed using the menus in AltosUI. The files that
1746 are written end in '.telem'. The after-flight
1747 data-dumped files will end in .eeprom and represent continuous data
1748 unlike the .telem files that are subject to losses
1749 along the RF data path.
1750 See the above instructions on what and how to save the eeprom stored
1751 data after physically retrieving your altimeter. Make sure to save
1752 the on-board data after each flight; while the TeleMetrum can store
1753 multiple flights, you never know when you'll lose the altimeter...
1754 </p></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a name="idp3991640"></a>Appendix A. Notes for Older Software</h1></div></div></div><p>
1755 <span class="emphasis"><em>
1756 Before AltosUI was written, using Altus Metrum devices required
1757 some finesse with the Linux command line. There was a limited
1758 GUI tool, ao-view, which provided functionality similar to the
1759 Monitor Flight window in AltosUI, but everything else was a
1760 fairly 80's experience. This appendix includes documentation for
1761 using that software.
1764 Both TeleMetrum and TeleDongle can be directly communicated
1765 with using USB ports. The first thing you should try after getting
1766 both units plugged into to your computer's USB port(s) is to run
1767 'ao-list' from a terminal-window to see what port-device-name each
1768 device has been assigned by the operating system.
1769 You will need this information to access the devices via their
1770 respective on-board firmware and data using other command line
1771 programs in the AltOS software suite.
1773 TeleMini can be communicated with through a TeleDongle device
1774 over the radio link. When first booted, TeleMini listens for a
1775 TeleDongle device and if it receives a packet, it goes into
1776 'idle' mode. Otherwise, it goes into 'pad' mode and waits to be
1777 launched. The easiest way to get it talking is to start the
1778 communication link on the TeleDongle and the power up the
1781 To access the device's firmware for configuration you need a terminal
1782 program such as you would use to talk to a modem. The software
1783 authors prefer using the program 'cu' which comes from the UUCP package
1784 on most Unix-like systems such as Linux. An example command line for
1785 cu might be 'cu -l /dev/ttyACM0', substituting the correct number
1786 indicated from running the
1787 ao-list program. Another reasonable terminal program for Linux is
1788 'cutecom'. The default 'escape'
1789 character used by CU (i.e. the character you use to
1790 issue commands to cu itself instead of sending the command as input
1791 to the connected device) is a '~'. You will need this for use in
1792 only two different ways during normal operations. First is to exit
1793 the program by sending a '~.' which is called a 'escape-disconnect'
1794 and allows you to close-out from 'cu'. The
1795 second use will be outlined later.
1797 All of the Altus Metrum devices share the concept of a two level
1798 command set in their firmware.
1799 The first layer has several single letter commands. Once
1800 you are using 'cu' (or 'cutecom') sending (typing) a '?'
1801 returns a full list of these
1802 commands. The second level are configuration sub-commands accessed
1803 using the 'c' command, for
1804 instance typing 'c?' will give you this second level of commands
1805 (all of which require the
1806 letter 'c' to access). Please note that most configuration options
1807 are stored only in Flash memory; TeleDongle doesn't provide any storage
1808 for these options and so they'll all be lost when you unplug it.
1810 Try setting these configuration ('c' or second level menu) values. A good
1811 place to start is by setting your call sign. By default, the boards
1812 use 'N0CALL' which is cute, but not exactly legal!
1813 Spend a few minutes getting comfortable with the units, their
1814 firmware, and 'cu' (or possibly 'cutecom').
1815 For instance, try to send
1816 (type) a 'c r 2' and verify the channel change by sending a 'c s'.
1817 Verify you can connect and disconnect from the units while in your
1818 terminal program by sending the escape-disconnect mentioned above.
1820 To set the radio frequency, use the 'c R' command to specify the
1821 radio transceiver configuration parameter. This parameter is computed
1822 using the desired frequency, 'F', the radio calibration parameter, 'C' (showed by the 'c s' command) and
1823 the standard calibration reference frequency, 'S', (normally 434.550MHz):
1824 </p><pre class="programlisting">
1827 Round the result to the nearest integer value.
1828 As with all 'c' sub-commands, follow this with a 'c w' to write the
1829 change to the parameter block in the on-board flash on
1830 your altimeter board if you want the change to stay in place across reboots.
1832 To set the apogee delay, use the 'c d' command.
1833 As with all 'c' sub-commands, follow this with a 'c w' to write the
1834 change to the parameter block in the on-board DataFlash chip.
1836 To set the main deployment altitude, use the 'c m' command.
1837 As with all 'c' sub-commands, follow this with a 'c w' to write the
1838 change to the parameter block in the on-board DataFlash chip.
1840 To calibrate the radio frequency, connect the UHF antenna port to a
1841 frequency counter, set the board to 434.550MHz, and use the 'C'
1842 command to generate a CW carrier. Wait for the transmitter temperature
1843 to stabilize and the frequency to settle down.
1844 Then, divide 434.550 MHz by the
1845 measured frequency and multiply by the current radio cal value show
1846 in the 'c s' command. For an unprogrammed board, the default value
1847 is 1186611. Take the resulting integer and program it using the 'c f'
1848 command. Testing with the 'C' command again should show a carrier
1849 within a few tens of Hertz of the intended frequency.
1850 As with all 'c' sub-commands, follow this with a 'c w' to write the
1851 change to the parameter block in the on-board DataFlash chip.
1853 Note that the 'reboot' command, which is very useful on the altimeters,
1854 will likely just cause problems with the dongle. The *correct* way
1855 to reset the dongle is just to unplug and re-plug it.
1857 A fun thing to do at the launch site and something you can do while
1858 learning how to use these units is to play with the radio link access
1859 between an altimeter and the TeleDongle. Be aware that you *must* create
1860 some physical separation between the devices, otherwise the link will
1861 not function due to signal overload in the receivers in each device.
1863 Now might be a good time to take a break and read the rest of this
1864 manual, particularly about the two "modes" that the altimeters
1865 can be placed in. TeleMetrum uses the position of the device when booting
1866 up will determine whether the unit is in "pad" or "idle" mode. TeleMini
1867 enters "idle" mode when it receives a command packet within the first 5 seconds
1868 of being powered up, otherwise it enters "pad" mode.
1870 You can access an altimeter in idle mode from the TeleDongle's USB
1871 connection using the radio link
1872 by issuing a 'p' command to the TeleDongle. Practice connecting and
1873 disconnecting ('~~' while using 'cu') from the altimeter. If
1874 you cannot escape out of the "p" command, (by using a '~~' when in
1875 CU) then it is likely that your kernel has issues. Try a newer version.
1877 Using this radio link allows you to configure the altimeter, test
1878 fire e-matches and igniters from the flight line, check pyro-match
1879 continuity and so forth. You can leave the unit turned on while it
1880 is in 'idle mode' and then place the
1881 rocket vertically on the launch pad, walk away and then issue a
1882 reboot command. The altimeter will reboot and start sending data
1883 having changed to the "pad" mode. If the TeleDongle is not receiving
1884 this data, you can disconnect 'cu' from the TeleDongle using the
1885 procedures mentioned above and THEN connect to the TeleDongle from
1886 inside 'ao-view'. If this doesn't work, disconnect from the
1887 TeleDongle, unplug it, and try again after plugging it back in.
1889 In order to reduce the chance of accidental firing of pyrotechnic
1890 charges, the command to fire a charge is intentionally somewhat
1891 difficult to type, and the built-in help is slightly cryptic to
1892 prevent accidental echoing of characters from the help text back at
1893 the board from firing a charge. The command to fire the apogee
1894 drogue charge is 'i DoIt drogue' and the command to fire the main
1895 charge is 'i DoIt main'.
1897 On TeleMetrum, the GPS will eventually find enough satellites, lock in on them,
1898 and 'ao-view' will both auditorily announce and visually indicate
1900 Now you can launch knowing that you have a good data path and
1901 good satellite lock for flight data and recovery. Remember
1902 you MUST tell ao-view to connect to the TeleDongle explicitly in
1903 order for ao-view to be able to receive data.
1905 The altimeters provide RDF (radio direction finding) tones on
1906 the pad, during descent and after landing. These can be used to
1907 locate the rocket using a directional antenna; the signal
1908 strength providing an indication of the direction from receiver to rocket.
1910 TeleMetrum also provides GPS tracking data, which can further simplify
1911 locating the rocket once it has landed. (The last good GPS data
1912 received before touch-down will be on the data screen of 'ao-view'.)
1914 Once you have recovered the rocket you can download the eeprom
1915 contents using either 'ao-dumplog' (or possibly 'ao-eeprom'), over
1916 either a USB cable or over the radio link using TeleDongle.
1917 And by following the man page for 'ao-postflight' you can create
1918 various data output reports, graphs, and even KML data to see the
1919 flight trajectory in Google-earth. (Moving the viewing angle making
1920 sure to connect the yellow lines while in Google-earth is the proper
1923 As for ao-view.... some things are in the menu but don't do anything
1924 very useful. The developers have stopped working on ao-view to focus
1925 on a new, cross-platform ground station program. So ao-view may or
1926 may not be updated in the future. Mostly you just use
1927 the Log and Device menus. It has a wonderful display of the incoming
1928 flight data and I am sure you will enjoy what it has to say to you
1929 once you enable the voice output!
1930 </p></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a name="idp4008072"></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="#idp4008720">1. TeleMetrum template</a></span></dt><dt><span class="section"><a href="#idp4016464">2. TeleMini template</a></span></dt></dl></div><p>
1931 These images, when printed, provide precise templates for the
1932 mounting holes in Altus Metrum flight computers
1933 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp4008720"></a>1. TeleMetrum template</h2></div></div></div><p>
1934 TeleMetrum has overall dimensions of 1.000 x 2.750 inches, and the
1935 mounting holes are sized for use with 4-40 or M3 screws.
1936 </p><div class="mediaobject"><a name="TeleMetrumTemplate"></a><object type="image/svg+xml" data="telemetrum.svg"></object></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp4016464"></a>2. TeleMini template</h2></div></div></div><p>
1937 TeleMini has overall dimensions of 0.500 x 1.500 inches, and the
1938 mounting holes are sized for use with 2-56 or M2 screws.
1939 </p><div class="mediaobject"><a name="TeleMiniTemplate"></a><object type="image/svg+xml" data="telemini.svg"></object></div></div></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a name="idp4018112"></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="#idp4019088">1. Radio Frequency</a></span></dt><dt><span class="section"><a href="#idp4022408">2. TeleMetrum Accelerometer</a></span></dt></dl></div><p>
1940 There are only two calibrations required for a TeleMetrum board, and
1941 only one for TeleDongle and TeleMini. All boards are shipped from
1942 the factory pre-calibrated, but the procedures are documented here
1943 in case they are ever needed. Re-calibration is not supported by
1944 AltosUI, you must connect to the board with a serial terminal program
1945 and interact directly with the on-board command interpreter to effect
1947 </p><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp4019088"></a>1. Radio Frequency</h2></div></div></div><p>
1948 The radio frequency is synthesized from a clock based on the 48 MHz
1949 crystal on the board. The actual frequency of this oscillator
1950 must be measured to generate a calibration constant. While our
1952 bandwidth is wide enough to allow boards to communicate even when
1953 their oscillators are not on exactly the same frequency, performance
1954 is best when they are closely matched.
1955 Radio frequency calibration requires a calibrated frequency counter.
1956 Fortunately, once set, the variation in frequency due to aging and
1957 temperature changes is small enough that re-calibration by customers
1958 should generally not be required.
1960 To calibrate the radio frequency, connect the UHF antenna port to a
1961 frequency counter, set the board to 434.550MHz, and use the 'C'
1962 command in the on-board command interpreter to generate a CW
1963 carrier. For TeleMetrum, this is best done over USB. For TeleMini,
1964 note that the only way to escape the 'C' command is via power cycle
1965 since the board will no longer be listening for commands once it
1966 starts generating a CW carrier.
1968 Wait for the transmitter temperature to stabilize and the frequency
1969 to settle down. Then, divide 434.550 MHz by the
1970 measured frequency and multiply by the current radio cal value show
1971 in the 'c s' command. For an unprogrammed board, the default value
1972 is 1186611. Take the resulting integer and program it using the 'c f'
1973 command. Testing with the 'C' command again should show a carrier
1974 within a few tens of Hertz of the intended frequency.
1975 As with all 'c' sub-commands, follow this with a 'c w' to write the
1976 change to the parameter block in the on-board DataFlash chip.
1978 Note that any time you re-do the radio frequency calibration, the
1979 radio frequency is reset to the default 434.550 Mhz. If you want
1980 to use another frequency, you will have to set that again after
1981 calibration is completed.
1982 </p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp4022408"></a>2. TeleMetrum Accelerometer</h2></div></div></div><p>
1983 The TeleMetrum accelerometer we use has its own 5 volt power
1985 the output must be passed through a resistive voltage divider to match
1986 the input of our 3.3 volt ADC. This means that unlike the barometric
1987 sensor, the output of the acceleration sensor is not ratio-metric to
1988 the ADC converter, and calibration is required. Explicitly
1989 calibrating the accelerometers also allows us to load any device
1990 from a Freescale family that includes at least +/- 40g, 50g, 100g,
1991 and 200g parts. Using gravity,
1992 a simple 2-point calibration yields acceptable results capturing both
1993 the different sensitivities and ranges of the different accelerometer
1994 parts and any variation in power supply voltages or resistor values
1995 in the divider network.
1997 To calibrate the acceleration sensor, use the 'c a 0' command. You
1998 will be prompted to orient the board vertically with the UHF antenna
1999 up and press a key, then to orient the board vertically with the
2000 UHF antenna down and press a key. Note that the accuracy of this
2001 calibration depends primarily on how perfectly vertical and still
2002 the board is held during the cal process. As with all 'c'
2003 sub-commands, follow this with a 'c w' to write the
2004 change to the parameter block in the on-board DataFlash chip.
2006 The +1g and -1g calibration points are included in each telemetry
2007 frame and are part of the header stored in onboard flash to be
2008 downloaded after flight. We always store and return raw ADC
2009 samples for each sensor... so nothing is permanently "lost" or
2010 "damaged" if the calibration is poor.
2012 In the unlikely event an accel cal goes badly, it is possible
2013 that TeleMetrum may always come up in 'pad mode' and as such not be
2014 listening to either the USB or radio link. If that happens,
2015 there is a special hook in the firmware to force the board back
2016 in to 'idle mode' so you can re-do the cal. To use this hook, you
2017 just need to ground the SPI clock pin at power-on. This pin is
2018 available as pin 2 on the 8-pin companion connector, and pin 1 is
2019 ground. So either carefully install a fine-gauge wire jumper
2020 between the two pins closest to the index hole end of the 8-pin
2021 connector, or plug in the programming cable to the 8-pin connector
2022 and use a small screwdriver or similar to short the two pins closest
2023 to the index post on the 4-pin end of the programming cable, and
2024 power up the board. It should come up in 'idle mode' (two beeps),
2026 </p></div></div><div class="appendix"><div class="titlepage"><div><div><h1 class="title"><a name="idp4027304"></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="idp4027664"></a>Version 1.21</h2></div></div></div><p>
2027 Version 1.2.1 is a minor release. It adds support for TeleBT and
2028 the AltosDroid application, provides several new features in
2029 AltosUI and fixes some bugs in the AltOS firmware.
2031 AltOS Firmware Changes
2032 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
2033 Add support for TeleBT
2034 </li><li class="listitem">
2035 In TeleMini recovery mode (when booted with the outer two
2036 debug pins connected together), the radio parameters are also
2037 set back to defaults (434.550MHz, N0CALL, factory radio cal).
2038 </li><li class="listitem">
2039 Add support for reflashing the SkyTraq GPS chips. This
2040 requires special host-side code which currently only exists
2042 </li><li class="listitem">
2043 Correct Kalman filter model error covariance matrix. The
2044 values used previously assumed continuous measurements instead
2045 of discrete measurements.
2046 </li><li class="listitem">
2047 Fix some bugs in the USB driver for TeleMetrum and TeleDongle
2048 that affected Windows users.
2049 </li><li class="listitem">
2050 Adjusted the automatic gain control parameters that affect
2051 receive performance for TeleDongle. Field tests indicate that this
2052 may improve receive performance somewhat.
2056 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
2057 Handle missing GPS lock in 'Descent' tab. Previously, if the
2058 GPS position of the pad was unknown, an exception would be
2059 raised, breaking the Descent tab contents.
2060 </li><li class="listitem">
2061 Improve the graph, adding tool-tips to show values near the
2062 cursor and making the displayed set of values configurable,
2063 adding all of the flight data as options while leaving the
2064 default settings alone so that the graph starts by showing
2065 height, speed and acceleration.
2066 </li><li class="listitem">
2067 Make the initial position of the AltosUI top level window
2068 configurable. Along with this change, the other windows will
2069 pop up at 'sensible' places now, instead of on top of one
2071 </li><li class="listitem">
2072 Add callsign to Monitor idle window and connecting
2073 dialogs. This makes it clear which callsign is being used so
2074 that the operator will be aware that it must match the flight
2075 computer value or no communication will work.
2076 </li><li class="listitem">
2077 When downloading flight data, display the block number so that
2078 the user has some sense of progress. Unfortunately, we don't
2079 know how many blocks will need to be downloaded, but at least
2080 it isn't just sitting there doing nothing for a long time.
2081 </li><li class="listitem">
2082 Add GPS data and a map to the graph window. This lets you see
2083 a complete summary of the flight without needing to 'replay'
2086 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp4028224"></a>Version 1.2</h2></div></div></div><p>
2087 Version 1.2 is a major release. It adds support for MicroPeak and
2088 the MicroPeak USB adapter.
2090 AltOS Firmware Changes
2091 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
2092 Add MicroPeak support. This includes support for the ATtiny85
2093 processor and adaptations to the core code to allow for
2094 devices too small to run the multi-tasking scheduler.
2097 MicroPeak UI changes
2098 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
2099 Added this new application
2102 Distribution Changes
2103 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
2104 Distribute Mac OS X packages in disk image ('.dmg') format to
2105 greatly simplify installation.
2106 </li><li class="listitem">
2107 Provide version numbers for the shared Java libraries to
2108 ensure that upgrades work properly, and to allow for multiple
2109 Altus Metrum software packages to be installed in the same
2110 directory at the same time.
2112 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp4028784"></a>Version 1.1.1</h2></div></div></div><p>
2113 Version 1.1.1 is a bug-fix release. It fixes a couple of bugs in
2114 AltosUI and one firmware bug that affects TeleMetrum version 1.0
2115 boards. Thanks to Bob Brown for help diagnosing the Google Earth
2116 file export issue, and for suggesting the addition of the Ground
2117 Distance value in the Descent tab.
2119 AltOS Firmware Changes
2120 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
2121 TeleMetrum v1.0 boards use the AT45DB081D flash memory part to
2122 store flight data, which is different from later TeleMetrum
2123 boards. The AltOS v1.1 driver for this chip couldn't erase
2124 memory, leaving it impossible to delete flight data or update
2125 configuration values. This bug doesn't affect newer TeleMetrum
2126 boards, and it doesn't affect the safety of rockets flying
2127 version 1.1 firmware.
2131 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
2132 Creating a Google Earth file (KML) from on-board flight data
2133 (EEPROM) would generate an empty file. The code responsible
2134 for reading the EEPROM file wasn't ever setting the GPS valid
2135 bits, and so the KML export code thought there was no GPS data
2137 </li><li class="listitem">
2138 The “Landed” tab was displaying all values in metric units,
2139 even when AltosUI was configured to display imperial
2140 units. Somehow I just missed this tab when doing the units stuff.
2141 </li><li class="listitem">
2142 The “Descent” tab displays the range to the rocket, which is a
2143 combination of the over-the-ground distance to the rockets
2144 current latitude/longitude and the height of the rocket. As
2145 such, it's useful for knowing how far away the rocket is, but
2146 difficult to use when estimating where the rocket might
2147 eventually land. A new “Ground Distance” field has been added
2148 which displays the distance to a spot right underneath the
2150 </li><li class="listitem">
2151 Sensor data wasn't being displayed for TeleMini flight
2152 computers in Monitor Idle mode, including things like battery
2153 voltage. The code that picked which kinds of data to fetch
2154 from the flight computer was missing a check for TeleMini when
2155 deciding whether to fetch the analog sensor data.
2157 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp4029344"></a>Version 1.1</h2></div></div></div><p>
2158 Version 1.1 is a minor release. It provides a few new features in AltosUI
2159 and the AltOS firmware and fixes bugs.
2161 AltOS Firmware Changes
2162 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
2163 Add apogee-lockout value. Overrides the apogee detection logic to
2164 prevent incorrect apogee charge firing.
2165 </li><li class="listitem">
2166 Fix a bug where the data reported in telemetry packets was
2168 </li><li class="listitem">
2169 Force the radio frequency to 434.550MHz when the debug clock
2170 pin is connected to ground at boot time. This provides a way
2171 to talk to a TeleMini which is configured to some unknown frequency.
2172 </li><li class="listitem">
2173 Provide RSSI values for Monitor Idle mode. This makes it easy to check radio
2174 range without needing to go to flight mode.
2175 </li><li class="listitem">
2176 Fix a bug which caused the old received telemetry packets to
2177 be retransmitted over the USB link when the radio was turned
2182 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
2183 Fix a bug that caused GPS ready to happen too quickly. The
2184 software was using every telemetry packet to signal new GPS
2185 data, which caused GPS ready to be signalled after 10 packets
2186 instead of 10 GPS updates.
2187 </li><li class="listitem">
2188 Fix Google Earth data export to work with recent versions. The
2189 google earth file loading code got a lot pickier, requiring
2190 some minor white space changes in the export code.
2191 </li><li class="listitem">
2192 Make the look-n-feel configurable, providing a choice from
2193 the available options.
2194 </li><li class="listitem">
2195 Add an 'Age' element to mark how long since a telemetry packet
2196 has been received. Useful to quickly gauge whether
2197 communications with the rocket are still active.
2198 </li><li class="listitem">
2199 Add 'Configure Ground Station' dialog to set the radio
2200 frequency used by a particular TeleDongle without having to go
2201 through the flight monitor UI.
2202 </li><li class="listitem">
2203 Add configuration for the new apogee-lockout value. A menu provides a list of
2204 reasonable values, or the value can be set by hand.
2205 </li><li class="listitem">
2206 Changed how flight data are downloaded. Now there's an initial
2207 dialog asking which flights to download, and after that
2208 finishes, a second dialog comes up asking which flights to delete.
2209 </li><li class="listitem">
2210 Re-compute time spent in each state for the flight graph; this
2211 figures out the actual boost and landing times instead of
2212 using the conservative values provide by the flight
2213 electronics. This improves the accuracy of the boost
2214 acceleration and main descent rate computations.
2215 </li><li class="listitem">
2216 Make AltosUI run on Mac OS Lion. The default Java heap space
2217 was dramatically reduced for this release causing much of the
2218 UI to fail randomly. This most often affected the satellite
2219 mapping download and displays.
2220 </li><li class="listitem">
2221 Change how data are displayed in the 'table' tab of the flight
2222 monitoring window. This eliminates entries duplicated from the
2223 header and adds both current altitude and pad altitude, which
2224 are useful in 'Monitor Idle' mode.
2225 </li><li class="listitem">
2226 Add Imperial units mode to present data in feet instead of
2229 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp4029904"></a>Version 1.0.1</h2></div></div></div><p>
2230 Version 1.0.1 is a major release, adding support for the TeleMini
2231 device and lots of new AltosUI features
2233 AltOS Firmware Changes
2234 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
2235 Add TeleMini v1.0 support. Firmware images for TeleMini are
2236 included in AltOS releases.
2237 </li><li class="listitem">
2238 Change telemetry to be encoded in multiple 32-byte packets. This
2239 enables support for TeleMini and other devices without requiring
2240 further updates to the TeleDongle firmware.
2241 </li><li class="listitem">
2242 Support operation of TeleMetrum with the antenna pointing
2243 aft. Previous firmware versions required the antenna to be
2244 pointing upwards, now there is a configuration option allowing
2245 the antenna to point aft, to aid installation in some airframes.
2246 </li><li class="listitem">
2247 Ability to disable telemetry. For airframes where an antenna
2248 just isn't possible, or where radio transmissions might cause
2249 trouble with other electronics, there's a configuration option
2250 to disable all telemetry. Note that the board will still
2251 enable the radio link in idle mode.
2252 </li><li class="listitem">
2253 Arbitrary frequency selection. The radios in Altus Metrum
2254 devices can be programmed to a wide range of frequencies, so
2255 instead of limiting devices to 10 pre-selected 'channels', the
2256 new firmware allows the user to choose any frequency in the
2257 70cm band. Note that the RF matching circuit on the boards is
2258 tuned for around 435MHz, so frequencies far from that may
2259 reduce the available range.
2260 </li><li class="listitem">
2261 Kalman-filter based flight-tracking. The model based sensor
2262 fusion approach of a Kalman filter means that AltOS now
2263 computes apogee much more accurately than before, generally
2264 within a fraction of a second. In addition, this approach
2265 allows the baro-only TeleMini device to correctly identify
2266 Mach transitions, avoiding the error-prone selection of a Mach
2271 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
2272 Wait for altimeter when using packet mode. Instead of quicly
2273 timing out when trying to initialize a packet mode
2274 configuration connection, AltosUI now waits indefinitely for
2275 the remote device to appear, providing a cancel button should
2276 the user get bored. This is necessary as the TeleMini can only
2277 be placed in "Idle" mode if AltosUI is polling it.
2278 </li><li class="listitem">
2279 Add main/apogee voltage graphs to the data plot. This provides
2280 a visual indication if the igniters fail before being fired.
2281 </li><li class="listitem">
2282 Scan for altimeter devices by watching the defined telemetry
2283 frequencies. This avoids the problem of remembering what
2284 frequency a device was configured to use, which is especially
2285 important with TeleMini which does not include a USB connection.
2286 </li><li class="listitem">
2287 Monitor altimeter state in "Idle" mode. This provides much of
2288 the information presented in the "Pad" dialog from the Monitor
2289 Flight command, monitoring the igniters, battery and GPS
2290 status withing requiring the flight computer to be armed and
2292 </li><li class="listitem">
2293 Pre-load map images from home. For those launch sites which
2294 don't provide free Wi-Fi, this allows you to download the
2295 necessary satellite images given the location of the launch
2296 site. A list of known launch sites is maintained at
2297 altusmetrum.org which AltosUI downloads to populate a menu; if
2298 you've got a launch site not on that list, please send the
2299 name of it, latitude and longitude along with a link to the
2300 web site of the controlling club to the altusmetrum mailing list.
2301 </li><li class="listitem">
2302 Flight statistics are now displayed in the Graph data
2303 window. These include max height/speed/accel, average descent
2304 rates and a few other bits of information. The Graph Data
2305 window can now be reached from the 'Landed' tab in the Monitor
2306 Flight window so you can immediately see the results of a
2309 </p></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp4030464"></a>Version 0.9.2</h2></div></div></div><p>
2310 Version 0.9.2 is an AltosUI bug-fix release, with no firmware changes.
2311 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
2312 Fix plotting problems due to missing file in the Mac OS install image.
2313 </li><li class="listitem">
2314 Always read whole eeprom blocks, mark empty records invalid, display parsing errors to user.
2315 </li><li class="listitem">
2316 Add software version to Configure AltosUI dialog
2317 </li></ul></div></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp4031024"></a>Version 0.9</h2></div></div></div><p>
2318 Version 0.9 adds a few new firmware features and accompanying
2319 AltosUI changes, along with new hardware support.
2320 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
2321 Support for TeleMetrum v1.1 hardware. Sources for the flash
2322 memory part used in v1.0 dried up, so v1.1 uses a different part
2323 which required a new driver and support for explicit flight log
2325 </li><li class="listitem">
2326 Multiple flight log support. This stores more than one flight
2327 log in the on-board flash memory. It also requires the user to
2328 explicitly erase flights so that you won't lose flight logs just
2329 because you fly the same board twice in one day.
2330 </li><li class="listitem">
2331 Telemetry support for devices with serial number >=
2332 256. Previous versions used a telemetry packet format that
2333 provided only 8 bits for the device serial number. This change
2334 requires that both ends of the telemetry link be running the 0.9
2335 firmware or they will not communicate.
2336 </li></ul></div></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp4031584"></a>Version 0.8</h2></div></div></div><p>
2337 Version 0.8 offers a major upgrade in the AltosUI
2338 interface. Significant new features include:
2339 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
2340 Post-flight graphing tool. This lets you explore the behaviour
2341 of your rocket after flight with a scroll-able and zoom-able
2342 chart showing the altitude, speed and acceleration of the
2343 airframe along with events recorded by the flight computer. You
2344 can export graphs to PNG files, or print them directly.
2345 </li><li class="listitem">
2346 Real-time moving map which overlays the in-progress flight on
2347 satellite imagery fetched from Google Maps. This lets you see in
2348 pictures where your rocket has landed, allowing you to plan
2349 recovery activities more accurately.
2350 </li><li class="listitem">
2351 Wireless recovery system testing. Prep your rocket for flight
2352 and test fire the deployment charges to make sure things work as
2353 expected. All without threading wires through holes in your
2355 </li><li class="listitem">
2356 Optimized flight status displays. Each flight state now has it's
2357 own custom 'tab' in the flight monitoring window so you can
2358 focus on the most important details. Pre-flight, the system
2359 shows a set of red/green status indicators for battery voltage,
2360 apogee/main igniter continutity and GPS reception. Wait until
2361 they're all green and your rocket is ready for flight. There are
2362 also tabs for ascent, descent and landing along with the
2363 original tabular view of the data.
2364 </li><li class="listitem">
2365 Monitor multiple flights simultaneously. If you have more than
2366 one TeleDongle, you can monitor a flight with each one on the
2368 </li><li class="listitem">
2369 Automatic flight monitoring at startup. Plug TeleDongle into the
2370 machine before starting AltosUI and it will automatically
2371 connect to it and prepare to monitor a flight.
2372 </li><li class="listitem">
2373 Exports Google Earth flight tracks. Using the Keyhole Markup
2374 Language (.kml) file format, this provides a 3D view of your
2375 rocket flight through the Google Earth program.
2376 </li></ul></div></div><div class="simplesect"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp4032144"></a>Version 0.7.1</h2></div></div></div><p>
2377 Version 0.7.1 is the first release containing our new cross-platform Java-based user interface. AltosUI can:
2378 </p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem">
2379 Receive and log telemetry from a connected TeleDongle
2380 device. All data received is saved to log files named with the
2381 current date and the connected rocket serial and flight
2382 numbers. There is no mode in which telemetry data will not be
2384 </li><li class="listitem">
2385 Download logged data from TeleMetrum devices, either through a
2386 direct USB connection or over the air through a TeleDongle
2388 </li><li class="listitem">
2389 Configure a TeleMetrum device, setting the radio channel,
2390 callsign, apogee delay and main deploy height. This can be done
2391 through either a USB connection or over a radio link via a
2393 </li><li class="listitem">
2394 Replay a flight in real-time. This takes a saved telemetry log
2395 or eeprom download and replays it through the user interface so
2396 you can relive your favorite rocket flights.
2397 </li><li class="listitem">
2398 Reprogram Altus Metrum devices. Using an Altus Metrum device
2399 connected via USB, another Altus Metrum device can be
2400 reprogrammed using the supplied programming cable between the
2402 </li><li class="listitem">
2403 Export Flight data to a comma-separated-values file. This takes
2404 either telemetry or on-board flight data and generates data
2405 suitable for use in external applications. All data is exported
2406 using standard units so that no device-specific knowledge is
2407 needed to handle the data.
2408 </li><li class="listitem">
2409 Speak to you during the flight. Instead of spending the flight
2410 hunched over your laptop looking at the screen, enjoy the view
2411 while the computer tells you what’s going on up there. During
2412 ascent, you hear the current flight state and altitude
2413 information. During descent, you get azimuth, elevation and
2414 range information to try and help you find your rocket in the
2415 air. Once on the ground, the direction and distance are
2417 </li></ul></div></div></div></div></body></html>