-<?xml version="1.0" encoding="utf-8" ?>
+<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
"/usr/share/xml/docbook/schema/dtd/4.5/docbookx.dtd">
<book>
<title>The Altus Metrum System</title>
- <subtitle>An Owner's Manual for TeleMetrum and TeleDongle Devices</subtitle>
+ <subtitle>An Owner's Manual for Altus Metrum Rocketry Electronics</subtitle>
<bookinfo>
<author>
<firstname>Bdale</firstname>
<surname>Towns</surname>
</author>
<copyright>
- <year>2010</year>
+ <year>2013</year>
<holder>Bdale Garbee and Keith Packard</holder>
</copyright>
<legalnotice>
</para>
</legalnotice>
<revhistory>
+ <revision>
+ <revnumber>1.3</revnumber>
+ <date>12 November 2013</date>
+ <revremark>
+ Updated for software version 1.3. Version 1.3 adds support
+ for TeleMega, TeleMetrum v2.0, TeleMini v2.0 and EasyMini
+ and fixes bugs in AltosUI and the AltOS firmware.
+ </revremark>
+ </revision>
+ <revision>
+ <revnumber>1.2.1</revnumber>
+ <date>21 May 2013</date>
+ <revremark>
+ Updated for software version 1.2. Version 1.2 adds support
+ for TeleBT and AltosDroid. It also adds a few minor features
+ and fixes bugs in AltosUI and the AltOS firmware.
+ </revremark>
+ </revision>
+ <revision>
+ <revnumber>1.2</revnumber>
+ <date>18 April 2013</date>
+ <revremark>
+ Updated for software version 1.2. Version 1.2 adds support
+ for MicroPeak and the MicroPeak USB interface.
+ </revremark>
+ </revision>
+ <revision>
+ <revnumber>1.1.1</revnumber>
+ <date>16 September 2012</date>
+ <revremark>
+ Updated for software version 1.1.1 Version 1.1.1 fixes a few
+ bugs found in version 1.1.
+ </revremark>
+ </revision>
+ <revision>
+ <revnumber>1.1</revnumber>
+ <date>13 September 2012</date>
+ <revremark>
+ Updated for software version 1.1. Version 1.1 has new
+ features but is otherwise compatible with version 1.0.
+ </revremark>
+ </revision>
+ <revision>
+ <revnumber>1.0</revnumber>
+ <date>24 August 2011</date>
+ <revremark>
+ Updated for software version 1.0. Note that 1.0 represents a
+ telemetry format change, meaning both ends of a link
+ (TeleMetrum/TeleMini and TeleDongle) must be updated or
+ communications will fail.
+ </revremark>
+ </revision>
+ <revision>
+ <revnumber>0.9</revnumber>
+ <date>18 January 2011</date>
+ <revremark>
+ Updated for software version 0.9. Note that 0.9 represents a
+ telemetry format change, meaning both ends of a link (TeleMetrum and
+ TeleDongle) must be updated or communications will fail.
+ </revremark>
+ </revision>
<revision>
<revnumber>0.8</revnumber>
<date>24 November 2010</date>
</revision>
</revhistory>
</bookinfo>
- <acknowledgements>
+ <dedication>
+ <title>Acknowledgments</title>
<para>
- Thanks to Bob Finch, W9YA, NAR 12965, TRA 12350 for writing "The
+ Thanks to Bob Finch, W9YA, NAR 12965, TRA 12350 for writing “The
Mere-Mortals Quick Start/Usage Guide to the Altus Metrum Starter
- Kit" which has turned into the Getting Started chapter in this
- book. Bob was one of our first customers for a production
- TeleMetrum, and the enthusiasm that led to his contribution of
- this section is immensely gratifying and highy appreciated!
+ Kit” which formed the basis of the original Getting Started chapter
+ in this manual. Bob was one of our first customers for a production
+ TeleMetrum, and his continued enthusiasm and contributions
+ are immensely gratifying and highly appreciated!
</para>
<para>
- And thanks to Anthony (AJ) Towns for contributing the
- AltosUI graphing and site map code and documentation. Free
- software means that our customers and friends can become our
+ And thanks to Anthony (AJ) Towns for major contributions including
+ the AltosUI graphing and site map code and associated documentation.
+ Free software means that our customers and friends can become our
collaborators, and we certainly appreciate this level of
- contribution.
+ contribution!
</para>
<para>
Have fun using these products, and we hope to meet all of you
NAR #88757, TRA #12200
</literallayout>
</para>
- </acknowledgements>
+ </dedication>
<chapter>
<title>Introduction and Overview</title>
<para>
future as you wish!
</para>
<para>
- The focal point of our community is TeleMetrum, a dual deploy altimeter
- with fully integrated GPS and radio telemetry as standard features, and
- a "companion interface" that will support optional capabilities in the
- future.
- </para>
- <para>
- Complementing TeleMetrum is TeleDongle, a USB to RF interface for
- communicating with TeleMetrum. Combined with your choice of antenna and
- notebook computer, TeleDongle and our associated user interface software
- form a complete ground station capable of logging and displaying in-flight
- telemetry, aiding rocket recovery, then processing and archiving flight
- data for analysis and review.
- </para>
- <para>
- More products will be added to the Altus Metrum family over time, and
- we currently envision that this will be a single, comprehensive manual
- for the entire product family.
- </para>
- </chapter>
- <chapter>
- <title>Getting Started</title>
- <para>
- The first thing to do after you check the inventory of parts in your
- "starter kit" is to charge the battery by plugging it into the
- corresponding socket of the TeleMetrum and then using the USB A to
- mini B
- cable to plug the Telemetrum into your computer's USB socket. The
- TeleMetrum circuitry will charge the battery whenever it is plugged
- in, because the TeleMetrum's on-off switch does NOT control the
- charging circuitry. When the GPS chip is initially searching for
- satellites, TeleMetrum will consume more current than it can pull
- from the usb port, so the battery must be attached in order to get
- satellite lock. Once GPS is locked, the current consumption goes back
- down enough to enable charging while
- running. So it's a good idea to fully charge the battery as your
- first item of business so there is no issue getting and maintaining
- satellite lock. The yellow charge indicator led will go out when the
- battery is nearly full and the charger goes to trickle charge. It
- can take several hours to fully recharge a deeply discharged battery.
+ The first device created for our community was TeleMetrum, a dual
+ deploy altimeter with fully integrated GPS and radio telemetry
+ as standard features, and a “companion interface” that will
+ support optional capabilities in the future. The latest version
+ of TeleMetrum, v2.0, has all of the same features but with
+ improved sensors and radio to offer increased performance.
</para>
<para>
- The other active device in the starter kit is the TeleDongle USB to
- RF interface. If you plug it in to your Mac or Linux computer it should
- "just work", showing up as a serial port device. Windows systems need
- driver information that is part of the AltOS download to know that the
- existing USB modem driver will work. If you are using Linux and are
- having problems, try moving to a fresher kernel (2.6.33 or newer), as
- the USB serial driver had ugly bugs in some earlier versions.
+ Our second device was TeleMini, a dual deploy altimeter with
+ radio telemetry and radio direction finding. The first version
+ of this device was only 13mm by 38mm (½ inch by 1½ inches) and
+ could fit easily in an 18mm air-frame. The latest version, v2.0,
+ includes a beeper, USB data download and extended on-board
+ flight logging, along with an improved barometric sensor.
</para>
<para>
- Next you should obtain and install the AltOS utilities. These include
- the AltosUI ground station program, current firmware images for
- TeleMetrum and TeleDongle, and a number of standalone utilities that
- are rarely needed. Pre-built binary packages are available for Debian
- Linux, Microsoft Windows, and recent MacOSX versions. Full sourcecode
- and build instructions for some other Linux variants are also available.
- The latest version may always be downloaded from
- <ulink url="http://altusmetrum.org/AltOS"/>.
+ TeleMega is our most sophisticated device, including six pyro
+ channels (four of which are fully programmable), integrated GPS,
+ integrated gyroscopes for staging/air-start inhibit and high
+ performance telemetry.
</para>
<para>
- Both Telemetrum and TeleDongle can be directly communicated
- with using USB ports. The first thing you should try after getting
- both units plugged into to your computer's usb port(s) is to run
- 'ao-list' from a terminal-window to see what port-device-name each
- device has been assigned by the operating system.
- You will need this information to access the devices via their
- respective on-board firmware and data using other command line
- programs in the AltOS software suite.
+ EasyMini is a dual-deploy altimeter with logging and built-in
+ USB data download.
</para>
<para>
- To access the device's firmware for configuration you need a terminal
- program such as you would use to talk to a modem. The software
- authors prefer using the program 'cu' which comes from the UUCP package
- on most Unix-like systems such as Linux. An example command line for
- cu might be 'cu -l /dev/ttyACM0', substituting the correct number
- indicated from running the
- ao-list program. Another reasonable terminal program for Linux is
- 'cutecom'. The default 'escape'
- character used by CU (i.e. the character you use to
- issue commands to cu itself instead of sending the command as input
- to the connected device) is a '~'. You will need this for use in
- only two different ways during normal operations. First is to exit
- the program by sending a '~.' which is called a 'escape-disconnect'
- and allows you to close-out from 'cu'. The
- second use will be outlined later.
+ TeleDongle was our first ground station, providing a USB to RF
+ interfaces for communicating with the altimeters. Combined with
+ your choice of antenna and notebook computer, TeleDongle and our
+ associated user interface software form a complete ground
+ station capable of logging and displaying in-flight telemetry,
+ aiding rocket recovery, then processing and archiving flight
+ data for analysis and review.
</para>
<para>
- Both TeleMetrum and TeleDongle share the concept of a two level
- command set in their firmware.
- The first layer has several single letter commands. Once
- you are using 'cu' (or 'cutecom') sending (typing) a '?'
- returns a full list of these
- commands. The second level are configuration sub-commands accessed
- using the 'c' command, for
- instance typing 'c?' will give you this second level of commands
- (all of which require the
- letter 'c' to access). Please note that most configuration options
- are stored only in DataFlash memory, and only TeleMetrum has this
- memory to save the various values entered like the channel number
- and your callsign when powered off. TeleDongle requires that you
- set these each time you plug it in, which ao-view can help with.
+ For a slightly more portable ground station experience that also
+ provides direct rocket recovery support, TeleBT offers flight
+ monitoring and data logging using a Bluetooth connection between
+ the receiver and an Android device that has the Altos Droid
+ application installed from the Google Play store.
</para>
<para>
- Try setting these config ('c' or second level menu) values. A good
- place to start is by setting your call sign. By default, the boards
- use 'N0CALL' which is cute, but not exactly legal!
- Spend a few minutes getting comfortable with the units, their
- firmware, and 'cu' (or possibly 'cutecom').
- For instance, try to send
- (type) a 'c r 2' and verify the channel change by sending a 'c s'.
- Verify you can connect and disconnect from the units while in your
- terminal program by sending the escape-disconnect mentioned above.
+ More products will be added to the Altus Metrum family over time, and
+ we currently envision that this will be a single, comprehensive manual
+ for the entire product family.
</para>
+ </chapter>
+ <chapter>
+ <title>Getting Started</title>
<para>
- Note that the 'reboot' command, which is very useful on TeleMetrum,
- will likely just cause problems with the dongle. The *correct* way
- to reset the dongle is just to unplug and re-plug it.
+ The first thing to do after you check the inventory of parts in your
+ “starter kit” is to charge the battery.
</para>
<para>
- A fun thing to do at the launch site and something you can do while
- learning how to use these units is to play with the rf-link access
- of the TeleMetrum from the TeleDongle. Be aware that you *must* create
- some physical separation between the devices, otherwise the link will
- not function due to signal overload in the receivers in each device.
+ For TeleMetrum and TeleMega, the battery can be charged by plugging it into the
+ corresponding socket of the device and then using the USB
+ cable to plug the flight computer into your computer's USB socket. The
+ on-board circuitry will charge the battery whenever it is plugged
+ in, because the on-off switch does NOT control the
+ charging circuitry.
</para>
<para>
- Now might be a good time to take a break and read the rest of this
- manual, particularly about the two "modes" that the TeleMetrum
- can be placed in and how the position of the TeleMetrum when booting
- up will determine whether the unit is in "pad" or "idle" mode.
+ On TeleMetrum v1 boards, when the GPS chip is initially
+ searching for satellites, TeleMetrum will consume more current
+ than it can pull from the USB port, so the battery must be
+ attached in order to get satellite lock. Once GPS is locked,
+ the current consumption goes back down enough to enable charging
+ while running. So it's a good idea to fully charge the battery
+ as your first item of business so there is no issue getting and
+ maintaining satellite lock. The yellow charge indicator led
+ will go out when the battery is nearly full and the charger goes
+ to trickle charge. It can take several hours to fully recharge a
+ deeply discharged battery.
</para>
<para>
- You can access a TeleMetrum in idle mode from the Teledongle's USB
- connection using the rf link
- by issuing a 'p' command to the TeleDongle. Practice connecting and
- disconnecting ('~~' while using 'cu') from the TeleMetrum. If
- you cannot escape out of the "p" command, (by using a '~~' when in
- CU) then it is likely that your kernel has issues. Try a newer version.
+ TeleMetrum v2.0 and TeleMega use a higher power battery charger,
+ allowing them to charge the battery while running the board at
+ maximum power. When the battery is charging, or when the board
+ is consuming a lot of power, the red LED will be lit. When the
+ battery is fully charged, the green LED will be lit. When the
+ battery is damaged or missing, both LEDs will be lit, which
+ appears yellow.
</para>
<para>
- Using this rf link allows you to configure the TeleMetrum, test
- fire e-matches and igniters from the flight line, check pyro-match
- continuity and so forth. You can leave the unit turned on while it
- is in 'idle mode' and then place the
- rocket vertically on the launch pad, walk away and then issue a
- reboot command. The TeleMetrum will reboot and start sending data
- having changed to the "pad" mode. If the TeleDongle is not receiving
- this data, you can disconnect 'cu' from the Teledongle using the
- procedures mentioned above and THEN connect to the TeleDongle from
- inside 'ao-view'. If this doesn't work, disconnect from the
- TeleDongle, unplug it, and try again after plugging it back in.
+ The Lithium Polymer TeleMini and EasyMini battery can be charged by
+ disconnecting it from the board and plugging it into a
+ standalone battery charger such as the LipoCharger product
+ included in TeleMini Starter Kits, and connecting that via a USB
+ cable to a laptop or other USB power source.
</para>
<para>
- Eventually the GPS will find enough satellites, lock in on them,
- and 'ao-view' will both auditorially announce and visually indicate
- that GPS is ready.
- Now you can launch knowing that you have a good data path and
- good satellite lock for flight data and recovery. Remember
- you MUST tell ao-view to connect to the TeleDongle explicitly in
- order for ao-view to be able to receive data.
+ You can also choose to use another battery with TeleMini v2.0
+ and EasyMini, anything supplying between 4 and 12 volts should
+ work fine (like a standard 9V battery), but if you are planning
+ to fire pyro charges, ground testing is required to verify that
+ the battery supplies enough current.
</para>
<para>
- Both RDF (radio direction finding) tones from the TeleMetrum and
- GPS trekking data are available and together are very useful in
- locating the rocket once it has landed. (The last good GPS data
- received before touch-down will be on the data screen of 'ao-view'.)
+ The other active device in the starter kit is the TeleDongle USB to
+ RF interface. If you plug it in to your Mac or Linux computer it should
+ “just work”, showing up as a serial port device. Windows systems need
+ driver information that is part of the AltOS download to know that the
+ existing USB modem driver will work. We therefore recommend installing
+ our software before plugging in TeleDongle if you are using a Windows
+ computer. If you are using Linux and are having problems, try moving
+ to a fresher kernel (2.6.33 or newer), as the USB serial driver had
+ ugly bugs in some earlier versions.
</para>
<para>
- Once you have recovered the rocket you can download the eeprom
- contents using either 'ao-dumplog' (or possibly 'ao-eeprom'), over
- either a USB cable or over the radio link using TeleDongle.
- And by following the man page for 'ao-postflight' you can create
- various data output reports, graphs, and even kml data to see the
- flight trajectory in google-earth. (Moving the viewing angle making
- sure to connect the yellow lines while in google-earth is the proper
- technique.)
+ Next you should obtain and install the AltOS software. These
+ include the AltosUI ground station program, current firmware
+ images for all of the hardware, and a number of standalone
+ utilities that are rarely needed. Pre-built binary packages are
+ available for Linux, Microsoft Windows, and recent MacOSX
+ versions. Full source code and build instructions are also
+ available. The latest version may always be downloaded from
+ <ulink url="http://altusmetrum.org/AltOS"/>.
</para>
<para>
- As for ao-view.... some things are in the menu but don't do anything
- very useful. The developers have stopped working on ao-view to focus
- on a new, cross-platform ground station program. So ao-view may or
- may not be updated in the future. Mostly you just use
- the Log and Device menus. It has a wonderful display of the incoming
- flight data and I am sure you will enjoy what it has to say to you
- once you enable the voice output!
+ If you're using a TeleBT instead of the TeleDongle, you'll want
+ to go install the Altos Droid application from the Google Play
+ store. You don't need a data plan to use Altos Droid, but
+ without network access, the Map view will be less useful as it
+ won't contain any map data. You can also use TeleBT connected
+ over USB with your laptop computer; it acts exactly like a
+ TeleDongle. Anywhere this manual talks about TeleDongle, you can
+ also read that as 'and TeleBT when connected via USB'.
</para>
- <section>
- <title>FAQ</title>
- <para>
- The altimeter (TeleMetrum) seems to shut off when disconnected from the
- computer. Make sure the battery is adequately charged. Remember the
- unit will pull more power than the USB port can deliver before the
- GPS enters "locked" mode. The battery charges best when TeleMetrum
- is turned off.
- </para>
- <para>
- It's impossible to stop the TeleDongle when it's in "p" mode, I have
- to unplug the USB cable? Make sure you have tried to "escape out" of
- this mode. If this doesn't work the reboot procedure for the
- TeleDongle *is* to simply unplug it. 'cu' however will retain it's
- outgoing buffer IF your "escape out" ('~~') does not work.
- At this point using either 'ao-view' (or possibly
- 'cutemon') instead of 'cu' will 'clear' the issue and allow renewed
- communication.
- </para>
- <para>
- The amber LED (on the TeleMetrum/altimeter) lights up when both
- battery and USB are connected. Does this mean it's charging?
- Yes, the yellow LED indicates the charging at the 'regular' rate.
- If the led is out but the unit is still plugged into a USB port,
- then the battery is being charged at a 'trickle' rate.
- </para>
- <para>
- There are no "dit-dah-dah-dit" sound like the manual mentions?
- That's the "pad" mode. Weak batteries might be the problem.
- It is also possible that the unit is horizontal and the output
- is instead a "dit-dit" meaning 'idle'.
- </para>
- <para>
- It's unclear how to use 'ao-view' and other programs when 'cu'
- is running. You cannot have more than one program connected to
- the TeleDongle at one time without apparent data loss as the
- incoming data will not make it to both programs intact.
- Disconnect whatever programs aren't currently being used.
- </para>
- <para>
- How do I save flight data?
- Live telemetry is written to file(s) whenever 'ao-view' is connected
- to the TeleDongle. The file area defaults to ~/altos
- but is easily changed using the menus in 'ao-view'. The files that
- are written end in '.telem'. The after-flight
- data-dumped files will end in .eeprom and represent continuous data
- unlike the rf-linked .telem files that are subject to the
- turnarounds/data-packaging time slots in the half-duplex rf data path.
- See the above instructions on what and how to save the eeprom stored
- data after physically retrieving your TeleMetrum. Make sure to save
- the on-board data after each flight, as the current firmware will
- over-write any previous flight data during a new flight.
- </para>
- </section>
- </chapter>
- <chapter>
- <title>Specifications</title>
- <itemizedlist>
- <listitem>
- <para>
- Recording altimeter for model rocketry.
- </para>
- </listitem>
- <listitem>
- <para>
- Supports dual deployment (can fire 2 ejection charges).
- </para>
- </listitem>
- <listitem>
- <para>
- 70cm ham-band transceiver for telemetry downlink.
- </para>
- </listitem>
- <listitem>
- <para>
- Barometric pressure sensor good to 45k feet MSL.
- </para>
- </listitem>
- <listitem>
- <para>
- 1-axis high-g accelerometer for motor characterization, capable of
- +/- 50g using default part.
- </para>
- </listitem>
- <listitem>
- <para>
- On-board, integrated GPS receiver with 5hz update rate capability.
- </para>
- </listitem>
- <listitem>
- <para>
- On-board 1 megabyte non-volatile memory for flight data storage.
- </para>
- </listitem>
- <listitem>
- <para>
- USB interface for battery charging, configuration, and data recovery.
- </para>
- </listitem>
- <listitem>
- <para>
- Fully integrated support for LiPo rechargeable batteries.
- </para>
- </listitem>
- <listitem>
- <para>
- Uses LiPo to fire e-matches, can be modiied to support
- optional separate pyro battery if needed.
- </para>
- </listitem>
- <listitem>
- <para>
- 2.75 x 1 inch board designed to fit inside 29mm airframe coupler tube.
- </para>
- </listitem>
- </itemizedlist>
</chapter>
<chapter>
<title>Handling Precautions</title>
<para>
- TeleMetrum is a sophisticated electronic device. When handled gently and
- properly installed in an airframe, it will deliver impressive results.
- However, like all electronic devices, there are some precautions you
- must take.
+ All Altus Metrum products are sophisticated electronic devices.
+ When handled gently and properly installed in an air-frame, they
+ will deliver impressive results. However, as with all electronic
+ devices, there are some precautions you must take.
</para>
<para>
- The Lithium Polymer rechargeable batteries used with TeleMetrum have an
+ The Lithium Polymer rechargeable batteries have an
extraordinary power density. This is great because we can fly with
much less battery mass than if we used alkaline batteries or previous
generation rechargeable batteries... but if they are punctured
or their leads are allowed to short, they can and will release their
energy very rapidly!
Thus we recommend that you take some care when handling our batteries
- and consider giving them some extra protection in your airframe. We
+ and consider giving them some extra protection in your air-frame. We
often wrap them in suitable scraps of closed-cell packing foam before
strapping them down, for example.
</para>
<para>
- The TeleMetrum barometric sensor is sensitive to sunlight. In normal
- mounting situations, it and all of the other surface mount components
- are "down" towards whatever the underlying mounting surface is, so
+ The barometric sensors used on all of our flight computers are
+ sensitive to sunlight. In normal mounting situations, the baro sensor
+ and all of the other surface mount components
+ are “down” towards whatever the underlying mounting surface is, so
this is not normally a problem. Please consider this, though, when
- designing an installation, for example, in a 29mm airframe with a
- see-through plastic payload bay.
+ designing an installation, for example, in an air-frame with a
+ see-through plastic payload bay. It is particularly important to
+ consider this with TeleMini v1.0, both because the baro sensor is on the
+ “top” of the board, and because many model rockets with payload bays
+ use clear plastic for the payload bay! Replacing these with an opaque
+ cardboard tube, painting them, or wrapping them with a layer of masking
+ tape are all reasonable approaches to keep the sensor out of direct
+ sunlight.
</para>
<para>
- The TeleMetrum barometric sensor sampling port must be able to
- "breathe",
+ The barometric sensor sampling port must be able to “breathe”,
both by not being covered by foam or tape or other materials that might
- directly block the hole on the top of the sensor, but also by having a
+ directly block the hole on the top of the sensor, and also by having a
suitable static vent to outside air.
</para>
<para>
- As with all other rocketry electronics, TeleMetrum must be protected
- from exposure to corrosive motor exhaust and ejection charge gasses.
- </para>
- </chapter>
- <chapter>
- <title>Hardware Overview</title>
- <para>
- TeleMetrum is a 1 inch by 2.75 inch circuit board. It was designed to
- fit inside coupler for 29mm airframe tubing, but using it in a tube that
- small in diameter may require some creativity in mounting and wiring
- to succeed! The default 1/4
- wave UHF wire antenna attached to the center of the nose-cone end of
- the board is about 7 inches long, and wiring for a power switch and
- the e-matches for apogee and main ejection charges depart from the
- fin can end of the board. Given all this, an ideal "simple" avionics
- bay for TeleMetrum should have at least 10 inches of interior length.
- </para>
- <para>
- A typical TeleMetrum installation using the on-board GPS antenna and
- default wire UHF antenna involves attaching only a suitable
- Lithium Polymer battery, a single pole switch for power on/off, and
- two pairs of wires connecting e-matches for the apogee and main ejection
- charges.
- </para>
- <para>
- By default, we use the unregulated output of the LiPo battery directly
- to fire ejection charges. This works marvelously with standard
- low-current e-matches like the J-Tek from MJG Technologies, and with
- Quest Q2G2 igniters. However, if you
- want or need to use a separate pyro battery, the board can be factory
- modified to do so. This involves cutting two traces and adding a jumper
- in a densely populated part of the board on TeleMetrum v1.0 and v1.1,
- along with installation of a pyro battery connector at location B2.
- </para>
- <para>
- We offer two choices of pyro and power switch connector, or you can
- choose neither and solder wires directly to the board. All three choices
- are reasonable depending on the constraints of your airframe. Our
- favorite option when there is sufficient room above the board is to use
- the Tyco pin header with polarization and locking. If you choose this
- option, you crimp individual wires for the power switch and e-matches
- into a mating connector, and installing and removing the TeleMetrum
- board from an airframe is as easy as plugging or unplugging two
- connectors. If the airframe will not support this much height or if
- you want to be able to directly attach e-match leads to the board, we
- offer a screw terminal block. This is very similar to what most other
- altimeter vendors provide and so may be the most familiar option.
- You'll need a very small straight blade screwdriver to connect
- and disconnect the board in this case, such as you might find in a
- jeweler's screwdriver set. Finally, you can forego both options and
- solder wires directly to the board, which may be the best choice for
- minimum diameter and/or minimum mass designs.
- </para>
- <para>
- For most airframes, the integrated GPS antenna and wire UHF antenna are
- a great combination. However, if you are installing in a carbon-fiber
- electronics bay which is opaque to RF signals, you may need to use
- off-board external antennas instead. In this case, you can order
- TeleMetrum with an SMA connector for the UHF antenna connection, and
- you can unplug the integrated GPS antenna and select an appropriate
- off-board GPS antenna with cable terminating in a U.FL connector.
+ As with all other rocketry electronics, Altus Metrum altimeters must
+ be protected from exposure to corrosive motor exhaust and ejection
+ charge gasses.
</para>
</chapter>
<chapter>
- <title>System Operation</title>
+ <title>Altus Metrum Hardware</title>
<section>
- <title>Firmware Modes </title>
+ <title>Overview</title>
<para>
- The AltOS firmware build for TeleMetrum has two fundamental modes,
- "idle" and "flight". Which of these modes the firmware operates in
- is determined by the orientation of the rocket (well, actually the
- board, of course...) at the time power is switched on. If the rocket
- is "nose up", then TeleMetrum assumes it's on a rail or rod being
- prepared for launch, so the firmware chooses flight mode. However,
- if the rocket is more or less horizontal, the firmware instead enters
- idle mode.
- </para>
- <para>
- At power on, you will hear three beeps
- ("S" in Morse code for startup) and then a pause while
- TeleMetrum completes initialization and self tests, and decides which
- mode to enter next.
- </para>
- <para>
- In flight or "pad" mode, TeleMetrum turns on the GPS system,
- engages the flight
- state machine, goes into transmit-only mode on the RF link sending
- telemetry, and waits for launch to be detected. Flight mode is
- indicated by an audible "di-dah-dah-dit" ("P" for pad) on the
- beeper, followed by
- beeps indicating the state of the pyrotechnic igniter continuity.
- One beep indicates apogee continuity, two beeps indicate
- main continuity, three beeps indicate both apogee and main continuity,
- and one longer "brap" sound indicates no continuity. For a dual
- deploy flight, make sure you're getting three beeps before launching!
- For apogee-only or motor eject flights, do what makes sense.
- </para>
- <para>
- In idle mode, you will hear an audible "di-dit" ("I" for idle), and
- the normal flight state machine is disengaged, thus
- no ejection charges will fire. TeleMetrum also listens on the RF
- link when in idle mode for packet mode requests sent from TeleDongle.
- Commands can be issued to a TeleMetrum in idle mode over either
- USB or the RF link equivalently.
- Idle mode is useful for configuring TeleMetrum, for extracting data
- from the on-board storage chip after flight, and for ground testing
- pyro charges.
- </para>
- <para>
- One "neat trick" of particular value when TeleMetrum is used with very
- large airframes, is that you can power the board up while the rocket
- is horizontal, such that it comes up in idle mode. Then you can
- raise the airframe to launch position, use a TeleDongle to open
- a packet connection, and issue a 'reset' command which will cause
- TeleMetrum to reboot, realize it's now nose-up, and thus choose
- flight mode. This is much safer than standing on the top step of a
- rickety step-ladder or hanging off the side of a launch tower with
- a screw-driver trying to turn on your avionics before installing
- igniters!
+ Here's the full set of Altus Metrum products, both in
+ production and retired.
</para>
+ <table frame='all'>
+ <title>Altus Metrum Electronics</title>
+ <tgroup cols='8' align='center' colsep='1' rowsep='1'>
+ <colspec align='center' colwidth='*' colname='Device'/>
+ <colspec align='center' colwidth='*' colname='Barometer'/>
+ <colspec align='center' colwidth='*' colname='Z-axis accelerometer'/>
+ <colspec align='center' colwidth='*' colname='GPS'/>
+ <colspec align='center' colwidth='*' colname='3D sensors'/>
+ <colspec align='center' colwidth='*' colname='Storage'/>
+ <colspec align='center' colwidth='*' colname='RF'/>
+ <colspec align='center' colwidth='*' colname='Battery'/>
+ <thead>
+ <row>
+ <entry align='center'>Device</entry>
+ <entry align='center'>Barometer</entry>
+ <entry align='center'>Z-axis accelerometer</entry>
+ <entry align='center'>GPS</entry>
+ <entry align='center'>3D sensors</entry>
+ <entry align='center'>Storage</entry>
+ <entry align='center'>RF Output</entry>
+ <entry align='center'>Battery</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry>TeleMetrum v1.0</entry>
+ <entry><para>MP3H6115 10km (33k')</para></entry>
+ <entry><para>MMA2202 50g</para></entry>
+ <entry>SkyTraq</entry>
+ <entry>-</entry>
+ <entry>1MB</entry>
+ <entry>10mW</entry>
+ <entry>3.7V</entry>
+ </row>
+ <row>
+ <entry>TeleMetrum v1.1</entry>
+ <entry><para>MP3H6115 10km (33k')</para></entry>
+ <entry><para>MMA2202 50g</para></entry>
+ <entry>SkyTraq</entry>
+ <entry>-</entry>
+ <entry>2MB</entry>
+ <entry>10mW</entry>
+ <entry>3.7V</entry>
+ </row>
+ <row>
+ <entry>TeleMetrum v1.2</entry>
+ <entry><para>MP3H6115 10km (33k')</para></entry>
+ <entry><para>ADXL78 70g</para></entry>
+ <entry>SkyTraq</entry>
+ <entry>-</entry>
+ <entry>2MB</entry>
+ <entry>10mW</entry>
+ <entry>3.7V</entry>
+ </row>
+ <row>
+ <entry>TeleMetrum v2.0</entry>
+ <entry><para>MS5607 30km (100k')</para></entry>
+ <entry><para>MMA6555 102g</para></entry>
+ <entry>uBlox Max-7Q</entry>
+ <entry>-</entry>
+ <entry>8MB</entry>
+ <entry>40mW</entry>
+ <entry>3.7V</entry>
+ </row>
+ <row>
+ <entry><para>TeleMini <?linebreak?>v1.0</para></entry>
+ <entry><para>MP3H6115 10km (33k')</para></entry>
+ <entry>-</entry>
+ <entry>-</entry>
+ <entry>-</entry>
+ <entry>5kB</entry>
+ <entry>10mW</entry>
+ <entry>3.7V</entry>
+ </row>
+ <row>
+ <entry>TeleMini <?linebreak?>v2.0</entry>
+ <entry><para>MS5607 30km (100k')</para></entry>
+ <entry>-</entry>
+ <entry>-</entry>
+ <entry>-</entry>
+ <entry>1MB</entry>
+ <entry>10mW</entry>
+ <entry>3.7-12V</entry>
+ </row>
+ <row>
+ <entry>EasyMini <?linebreak?>v1.0</entry>
+ <entry><para>MS5607 30km (100k')</para></entry>
+ <entry>-</entry>
+ <entry>-</entry>
+ <entry>-</entry>
+ <entry>1MB</entry>
+ <entry>-</entry>
+ <entry>3.7-12V</entry>
+ </row>
+ <row>
+ <entry>TeleMega <?linebreak?>v1.0</entry>
+ <entry><para>MS5607 30km (100k')</para></entry>
+ <entry><para>MMA6555 102g</para></entry>
+ <entry>uBlox Max-7Q</entry>
+ <entry><para>MPU6000 HMC5883</para></entry>
+ <entry>8MB</entry>
+ <entry>40mW</entry>
+ <entry>3.7V</entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
+ <table frame='all'>
+ <title>Altus Metrum Boards</title>
+ <tgroup cols='6' align='center' colsep='1' rowsep='1'>
+ <colspec align='center' colwidth='*' colname='Device'/>
+ <colspec align='center' colwidth='*' colname='Connectors'/>
+ <colspec align='center' colwidth='*' colname='Screw Terminals'/>
+ <colspec align='center' colwidth='*' colname='Width'/>
+ <colspec align='center' colwidth='*' colname='Length'/>
+ <colspec align='center' colwidth='*' colname='Tube Size'/>
+ <thead>
+ <row>
+ <entry align='center'>Device</entry>
+ <entry align='center'>Connectors</entry>
+ <entry align='center'>Screw Terminals</entry>
+ <entry align='center'>Width</entry>
+ <entry align='center'>Length</entry>
+ <entry align='center'>Tube Size</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry>TeleMetrum</entry>
+ <entry><para>
+ Antenna<?linebreak?>
+ Debug<?linebreak?>
+ Companion<?linebreak?>
+ USB<?linebreak?>
+ Battery
+ </para></entry>
+ <entry><para>Apogee pyro <?linebreak?>Main pyro <?linebreak?>Switch</para></entry>
+ <entry>1 inch (2.54cm)</entry>
+ <entry>2 ¾ inch (6.99cm)</entry>
+ <entry>29mm coupler</entry>
+ </row>
+ <row>
+ <entry><para>TeleMini <?linebreak?>v1.0</para></entry>
+ <entry><para>
+ Antenna<?linebreak?>
+ Debug<?linebreak?>
+ Battery
+ </para></entry>
+ <entry><para>
+ Apogee pyro <?linebreak?>
+ Main pyro
+ </para></entry>
+ <entry>½ inch (1.27cm)</entry>
+ <entry>1½ inch (3.81cm)</entry>
+ <entry>18mm airframe</entry>
+ </row>
+ <row>
+ <entry>TeleMini <?linebreak?>v2.0</entry>
+ <entry><para>
+ Antenna<?linebreak?>
+ Debug<?linebreak?>
+ USB<?linebreak?>
+ Battery
+ </para></entry>
+ <entry><para>
+ Apogee pyro <?linebreak?>
+ Main pyro <?linebreak?>
+ Battery <?linebreak?>
+ Switch
+ </para></entry>
+ <entry>0.8 inch (2.03cm)</entry>
+ <entry>1½ inch (3.81cm)</entry>
+ <entry>24mm coupler</entry>
+ </row>
+ <row>
+ <entry>EasyMini</entry>
+ <entry><para>
+ Debug<?linebreak?>
+ USB<?linebreak?>
+ Battery
+ </para></entry>
+ <entry><para>
+ Apogee pyro <?linebreak?>
+ Main pyro <?linebreak?>
+ Battery <?linebreak?>
+ Switch
+ </para></entry>
+ <entry>0.8 inch (2.03cm)</entry>
+ <entry>1½ inch (3.81cm)</entry>
+ <entry>24mm coupler</entry>
+ </row>
+ <row>
+ <entry>TeleMega</entry>
+ <entry><para>
+ Antenna<?linebreak?>
+ Debug<?linebreak?>
+ Companion<?linebreak?>
+ USB<?linebreak?>
+ Battery
+ </para></entry>
+ <entry><para>
+ Apogee pyro <?linebreak?>
+ Main pyro<?linebreak?>
+ Pyro A-D<?linebreak?>
+ Switch<?linebreak?>
+ Pyro battery
+ </para></entry>
+ <entry>1¼ inch (3.18cm)</entry>
+ <entry>3¼ inch (8.26cm)</entry>
+ <entry>38mm coupler</entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
</section>
<section>
- <title>GPS </title>
+ <title>TeleMetrum</title>
<para>
- TeleMetrum includes a complete GPS receiver. See a later section for
- a brief explanation of how GPS works that will help you understand
- the information in the telemetry stream. The bottom line is that
- the TeleMetrum GPS receiver needs to lock onto at least four
- satellites to obtain a solid 3 dimensional position fix and know
- what time it is!
+ TeleMetrum is a 1 inch by 2¾ inch circuit board. It was designed to
+ fit inside coupler for 29mm air-frame tubing, but using it in a tube that
+ small in diameter may require some creativity in mounting and wiring
+ to succeed! The presence of an accelerometer means TeleMetrum should
+ be aligned along the flight axis of the airframe, and by default the ¼
+ wave UHF wire antenna should be on the nose-cone end of the board. The
+ antenna wire is about 7 inches long, and wiring for a power switch and
+ the e-matches for apogee and main ejection charges depart from the
+ fin can end of the board, meaning an ideal “simple” avionics
+ bay for TeleMetrum should have at least 10 inches of interior length.
</para>
+ </section>
+ <section>
+ <title>TeleMini</title>
<para>
- TeleMetrum provides backup power to the GPS chip any time a LiPo
- battery is connected. This allows the receiver to "warm start" on
- the launch rail much faster than if every power-on were a "cold start"
- for the GPS receiver. In typical operations, powering up TeleMetrum
- on the flight line in idle mode while performing final airframe
- preparation will be sufficient to allow the GPS receiver to cold
- start and acquire lock. Then the board can be powered down during
- RSO review and installation on a launch rod or rail. When the board
- is turned back on, the GPS system should lock very quickly, typically
- long before igniter installation and return to the flight line are
- complete.
+ TeleMini v1.0 is ½ inches by 1½ inches. It was
+ designed to fit inside an 18mm air-frame tube, but using it in
+ a tube that small in diameter may require some creativity in
+ mounting and wiring to succeed! Since there is no
+ accelerometer, TeleMini can be mounted in any convenient
+ orientation. The default ¼ wave UHF wire antenna attached to
+ the center of one end of the board is about 7 inches long. Two
+ wires for the power switch are connected to holes in the
+ middle of the board. Screw terminals for the e-matches for
+ apogee and main ejection charges depart from the other end of
+ the board, meaning an ideal “simple” avionics bay for TeleMini
+ should have at least 9 inches of interior length.
+ </para>
+ <para>
+ TeleMini v2.0 is 0.8 inches by 1½ inches. It adds more
+ on-board data logging memory, a built-in USB connector and
+ screw terminals for the battery and power switch. The larger
+ board fits in a 24mm coupler. There's also a battery connector
+ for a LiPo battery if you want to use one of those.
</para>
</section>
<section>
- <title>Ground Testing </title>
+ <title>EasyMini</title>
<para>
- An important aspect of preparing a rocket using electronic deployment
- for flight is ground testing the recovery system. Thanks
- to the bi-directional RF link central to the Altus Metrum system,
- this can be accomplished in a TeleMetrum-equipped rocket without as
- much work as you may be accustomed to with other systems. It can
- even be fun!
+ EasyMini is built on a 0.8 inch by 1½ inch circuit board. It's
+ designed to fit in a 24mm coupler tube. The connectors and
+ screw terminals match TeleMini, so you can swap an EasyMini
+ with a TeleMini.
+ </para>
+ </section>
+ <section>
+ <title>TeleMega</title>
+ <para>
+ TeleMega is a 1¼ inch by 3¼ inch circuit board. It was
+ designed to easily fit in a 38mm coupler. Like TeleMetrum,
+ TeleMega has an accelerometer and so it must be mounted so that
+ the board is aligned with the flight axis. It can be mounted
+ either antenna up or down.
+ </para>
+ </section>
+ <section>
+ <title>Flight Data Recording</title>
+ <para>
+ Each flight computer logs data at 100 samples per second
+ during ascent and 10 samples per second during descent, except
+ for TeleMini v1.0, which records ascent at 10 samples per
+ second and descent at 1 sample per second. Data are logged to
+ an on-board flash memory part, which can be partitioned into
+ several equal-sized blocks, one for each flight.
+ </para>
+ <table frame='all'>
+ <title>Data Storage on Altus Metrum altimeters</title>
+ <tgroup cols='4' align='center' colsep='1' rowsep='1'>
+ <colspec align='center' colwidth='*' colname='Device'/>
+ <colspec align='center' colwidth='*' colname='Bytes per sample'/>
+ <colspec align='center' colwidth='*' colname='Total storage'/>
+ <colspec align='center' colwidth='*' colname='Minutes of
+ full-rate'/>
+ <thead>
+ <row>
+ <entry align='center'>Device</entry>
+ <entry align='center'>Bytes per Sample</entry>
+ <entry align='center'>Total Storage</entry>
+ <entry align='center'>Minutes at Full Rate</entry>
+ </row>
+ </thead>
+ <tbody>
+ <row>
+ <entry>TeleMetrum v1.0</entry>
+ <entry>8</entry>
+ <entry>1MB</entry>
+ <entry>20</entry>
+ </row>
+ <row>
+ <entry>TeleMetrum v1.1 v1.2</entry>
+ <entry>8</entry>
+ <entry>2MB</entry>
+ <entry>40</entry>
+ </row>
+ <row>
+ <entry>TeleMetrum v2.0</entry>
+ <entry>16</entry>
+ <entry>8MB</entry>
+ <entry>80</entry>
+ </row>
+ <row>
+ <entry>TeleMini v1.0</entry>
+ <entry>2</entry>
+ <entry>5kB</entry>
+ <entry>4</entry>
+ </row>
+ <row>
+ <entry>TeleMini v2.0</entry>
+ <entry>16</entry>
+ <entry>1MB</entry>
+ <entry>10</entry>
+ </row>
+ <row>
+ <entry>EasyMini</entry>
+ <entry>16</entry>
+ <entry>1MB</entry>
+ <entry>10</entry>
+ </row>
+ <row>
+ <entry>TeleMega</entry>
+ <entry>32</entry>
+ <entry>8MB</entry>
+ <entry>40</entry>
+ </row>
+ </tbody>
+ </tgroup>
+ </table>
+ <para>
+ The on-board flash is partitioned into separate flight logs,
+ each of a fixed maximum size. Increase the maximum size of
+ each log and you reduce the number of flights that can be
+ stored. Decrease the size and you can store more flights.
</para>
<para>
- Just prep the rocket for flight, then power up TeleMetrum while the
- airframe is horizontal. This will cause the firmware to go into
- "idle" mode, in which the normal flight state machine is disabled and
- charges will not fire without manual command. Then, establish an
- RF packet connection from a TeleDongle-equipped computer using the
- P command from a safe distance. You can now command TeleMetrum to
- fire the apogee or main charges to complete your testing.
+ Configuration data is also stored in the flash memory on
+ TeleMetrum v1.x, TeleMini and EasyMini. This consumes 64kB
+ of flash space. This configuration space is not available
+ for storing flight log data. TeleMetrum v2.0 and TeleMega
+ store configuration data in a bit of eeprom available within
+ the processor chip, leaving that space available in flash for
+ more flight data.
</para>
<para>
- In order to reduce the chance of accidental firing of pyrotechnic
- charges, the command to fire a charge is intentionally somewhat
- difficult to type, and the built-in help is slightly cryptic to
- prevent accidental echoing of characters from the help text back at
- the board from firing a charge. The command to fire the apogee
- drogue charge is 'i DoIt drogue' and the command to fire the main
- charge is 'i DoIt main'.
+ To compute the amount of space needed for a single flight, you
+ can multiply the expected ascent time (in seconds) by 100
+ times bytes-per-sample, multiply the expected descent time (in
+ seconds) by 10 times the bytes per sample and add the two
+ together. That will slightly under-estimate the storage (in
+ bytes) needed for the flight. For instance, a TeleMetrum v2.0 flight spending
+ 20 seconds in ascent and 150 seconds in descent will take
+ about (20 * 1600) + (150 * 160) = 56000 bytes of storage. You
+ could store dozens of these flights in the on-board flash.
+ </para>
+ <para>
+ The default size allows for several flights on each flight
+ computer, except for TeleMini v1.0, which only holds data for a
+ single flight. You can adjust the size.
+ </para>
+ <para>
+ Altus Metrum flight computers will not overwrite existing
+ flight data, so be sure to download flight data and erase it
+ from the flight computer before it fills up. The flight
+ computer will still successfully control the flight even if it
+ cannot log data, so the only thing you will lose is the data.
</para>
</section>
<section>
- <title>Radio Link </title>
+ <title>Installation</title>
<para>
- The chip our boards are based on incorporates an RF transceiver, but
- it's not a full duplex system... each end can only be transmitting or
- receiving at any given moment. So we had to decide how to manage the
- link.
+ A typical installation involves attaching
+ only a suitable battery, a single pole switch for
+ power on/off, and two pairs of wires connecting e-matches for the
+ apogee and main ejection charges. All Altus Metrum products are
+ designed for use with single-cell batteries with 3.7 volts
+ nominal. TeleMini v2.0 and EasyMini may also be used with other
+ batteries as long as they supply between 4 and 12 volts.
</para>
<para>
- By design, TeleMetrum firmware listens for an RF connection when
- it's in "idle mode" (turned on while the rocket is horizontal), which
- allows us to use the RF link to configure the rocket, do things like
- ejection tests, and extract data after a flight without having to
- crack open the airframe. However, when the board is in "flight
- mode" (turned on when the rocket is vertical) the TeleMetrum only
- transmits and doesn't listen at all. That's because we want to put
- ultimate priority on event detection and getting telemetry out of
- the rocket and out over
- the RF link in case the rocket crashes and we aren't able to extract
- data later...
+ The battery connectors are a standard 2-pin JST connector and
+ match batteries sold by Spark Fun. These batteries are
+ single-cell Lithium Polymer batteries that nominally provide 3.7
+ volts. Other vendors sell similar batteries for RC aircraft
+ using mating connectors, however the polarity for those is
+ generally reversed from the batteries used by Altus Metrum
+ products. In particular, the Tenergy batteries supplied for use
+ in Featherweight flight computers are not compatible with Altus
+ Metrum flight computers or battery chargers. <emphasis>Check
+ polarity and voltage before connecting any battery not purchased
+ from Altus Metrum or Spark Fun.</emphasis>
+ </para>
+ <para>
+ By default, we use the unregulated output of the battery directly
+ to fire ejection charges. This works marvelously with standard
+ low-current e-matches like the J-Tek from MJG Technologies, and with
+ Quest Q2G2 igniters. However, if you want or need to use a separate
+ pyro battery, check out the “External Pyro Battery” section in this
+ manual for instructions on how to wire that up. The altimeters are
+ designed to work with an external pyro battery of no more than 15 volts.
+
</para>
<para>
- We don't use a 'normal packet radio' mode because they're just too
- inefficient. The GFSK modulation we use is just FSK with the
- baseband pulses passed through a
- Gaussian filter before they go into the modulator to limit the
- transmitted bandwidth. When combined with the hardware forward error
- correction support in the cc1111 chip, this allows us to have a very
- robust 38.4 kilobit data link with only 10 milliwatts of transmit power,
- a whip antenna in the rocket, and a hand-held Yagi on the ground. We've
- had flights to above 21k feet AGL with good reception, and calculations
- suggest we should be good to well over 40k feet AGL with a 5-element yagi on
- the ground. We hope to fly boards to higher altitudes soon, and would
- of course appreciate customer feedback on performance in higher
- altitude flights!
+ Ejection charges are wired directly to the screw terminal block
+ at the aft end of the altimeter. You'll need a very small straight
+ blade screwdriver for these screws, such as you might find in a
+ jeweler's screwdriver set.
+ </para>
+ <para>
+ Except for TeleMini v1.0, the flight computers also use the
+ screw terminal block for the power switch leads. On TeleMini v1.0,
+ the power switch leads are soldered directly to the board and
+ can be connected directly to a switch.
+ </para>
+ <para>
+ For most air-frames, the integrated antennas are more than
+ adequate. However, if you are installing in a carbon-fiber or
+ metal electronics bay which is opaque to RF signals, you may need to
+ use off-board external antennas instead. In this case, you can
+ order an altimeter with an SMA connector for the UHF antenna
+ connection, and, on TeleMetrum v1, you can unplug the integrated GPS
+ antenna and select an appropriate off-board GPS antenna with
+ cable terminating in a U.FL connector.
</para>
</section>
+ </chapter>
+ <chapter>
+ <title>System Operation</title>
<section>
- <title>Configurable Parameters</title>
+ <title>Firmware Modes </title>
<para>
- Configuring a TeleMetrum board for flight is very simple. Because we
- have both acceleration and pressure sensors, there is no need to set
- a "mach delay", for example. The few configurable parameters can all
- be set using a simple terminal program over the USB port or RF link
- via TeleDongle.
+ The AltOS firmware build for the altimeters has two
+ fundamental modes, “idle” and “flight”. Which of these modes
+ the firmware operates in is determined at start up time. For
+ TeleMetrum, the mode is controlled by the orientation of the
+ rocket (well, actually the board, of course...) at the time
+ power is switched on. If the rocket is “nose up”, then
+ TeleMetrum assumes it's on a rail or rod being prepared for
+ launch, so the firmware chooses flight mode. However, if the
+ rocket is more or less horizontal, the firmware instead enters
+ idle mode. Since TeleMini v2.0 and EasyMini don't have an
+ accelerometer we can use to determine orientation, “idle” mode
+ is selected if the board is connected via USB to a computer,
+ otherwise the board enters “flight” mode. TeleMini v1.0
+ selects “idle” mode if it receives a command packet within the
+ first five seconds of operation.
</para>
- <section>
- <title>Radio Channel</title>
- <para>
- Our firmware supports 10 channels. The default channel 0 corresponds
- to a center frequency of 434.550 Mhz, and channels are spaced every
- 100 khz. Thus, channel 1 is 434.650 Mhz, and channel 9 is 435.550 Mhz.
- At any given launch, we highly recommend coordinating who will use
- each channel and when to avoid interference. And of course, both
- TeleMetrum and TeleDongle must be configured to the same channel to
- successfully communicate with each other.
- </para>
- <para>
- To set the radio channel, use the 'c r' command, like 'c r 3' to set
- channel 3.
- As with all 'c' sub-commands, follow this with a 'c w' to write the
- change to the parameter block in the on-board DataFlash chip on
- your TeleMetrum board if you want the change to stay in place across reboots.
- </para>
- </section>
- <section>
- <title>Apogee Delay</title>
- <para>
- Apogee delay is the number of seconds after TeleMetrum detects flight
- apogee that the drogue charge should be fired. In most cases, this
- should be left at the default of 0. However, if you are flying
- redundant electronics such as for an L3 certification, you may wish
- to set one of your altimeters to a positive delay so that both
- primary and backup pyrotechnic charges do not fire simultaneously.
- </para>
- <para>
- To set the apogee delay, use the 'c d' command.
- As with all 'c' sub-commands, follow this with a 'c w' to write the
- change to the parameter block in the on-board DataFlash chip.
- </para>
- <para>
- Please note that the TeleMetrum apogee detection algorithm always
- fires a fraction of a second *after* apogee. If you are also flying
- an altimeter like the PerfectFlite MAWD, which only supports selecting
- 0 or 1 seconds of apogee delay, you may wish to set the MAWD to 0
- seconds delay and set the TeleMetrum to fire your backup 2 or 3
- seconds later to avoid any chance of both charges firing
- simultaneously. We've flown several airframes this way quite happily,
- including Keith's successful L3 cert.
- </para>
- </section>
- <section>
- <title>Main Deployment Altitude</title>
- <para>
- By default, TeleMetrum will fire the main deployment charge at an
- elevation of 250 meters (about 820 feet) above ground. We think this
- is a good elevation for most airframes, but feel free to change this
- to suit. In particular, if you are flying two altimeters, you may
- wish to set the
- deployment elevation for the backup altimeter to be something lower
- than the primary so that both pyrotechnic charges don't fire
- simultaneously.
- </para>
- <para>
- To set the main deployment altitude, use the 'c m' command.
- As with all 'c' sub-commands, follow this with a 'c w' to write the
- change to the parameter block in the on-board DataFlash chip.
- </para>
- </section>
- </section>
- <section>
- <title>Calibration</title>
<para>
- There are only two calibrations required for a TeleMetrum board, and
- only one for TeleDongle.
+ At power on, you will hear three beeps or see three flashes
+ (“S” in Morse code for start up) and then a pause while
+ the altimeter completes initialization and self test, and decides
+ which mode to enter next.
+ </para>
+ <para>
+ In flight or “pad” mode, the altimeter engages the flight
+ state machine, goes into transmit-only mode to
+ send telemetry, and waits for launch to be detected.
+ Flight mode is indicated by an “di-dah-dah-dit” (“P” for pad)
+ on the beeper or lights, followed by beeps or flashes
+ indicating the state of the pyrotechnic igniter continuity.
+ One beep/flash indicates apogee continuity, two beeps/flashes
+ indicate main continuity, three beeps/flashes indicate both
+ apogee and main continuity, and one longer “brap” sound or
+ rapidly alternating lights indicates no continuity. For a
+ dual deploy flight, make sure you're getting three beeps or
+ flashes before launching! For apogee-only or motor eject
+ flights, do what makes sense.
+ </para>
+ <para>
+ If idle mode is entered, you will hear an audible “di-dit” or
+ see two short flashes (“I” for idle), and the flight state
+ machine is disengaged, thus no ejection charges will fire.
+ The altimeters also listen for the radio link when in idle
+ mode for requests sent via TeleDongle. Commands can be issued
+ in idle mode over either USB or the radio link
+ equivalently. TeleMini v1.0 only has the radio link. Idle
+ mode is useful for configuring the altimeter, for extracting
+ data from the on-board storage chip after flight, and for
+ ground testing pyro charges.
+ </para>
+ <para>
+ One “neat trick” of particular value when TeleMetrum or TeleMega are used with
+ very large air-frames, is that you can power the board up while the
+ rocket is horizontal, such that it comes up in idle mode. Then you can
+ raise the air-frame to launch position, and issue a 'reset' command
+ via TeleDongle over the radio link to cause the altimeter to reboot and
+ come up in flight mode. This is much safer than standing on the top
+ step of a rickety step-ladder or hanging off the side of a launch
+ tower with a screw-driver trying to turn on your avionics before
+ installing igniters!
+ </para>
+ <para>
+ TeleMini v1.0 is configured solely via the radio link. Of course, that
+ means you need to know the TeleMini radio configuration values
+ or you won't be able to communicate with it. For situations
+ when you don't have the radio configuration values, TeleMini v1.0
+ offers an 'emergency recovery' mode. In this mode, TeleMini is
+ configured as follows:
+ <itemizedlist>
+ <listitem>
+ <para>
+ Sets the radio frequency to 434.550MHz
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Sets the radio calibration back to the factory value.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Sets the callsign to N0CALL
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Does not go to 'pad' mode after five seconds.
+ </para>
+ </listitem>
+ </itemizedlist>
+ </para>
+ <para>
+ To get into 'emergency recovery' mode, first find the row of
+ four small holes opposite the switch wiring. Using a short
+ piece of small gauge wire, connect the outer two holes
+ together, then power TeleMini up. Once the red LED is lit,
+ disconnect the wire and the board should signal that it's in
+ 'idle' mode after the initial five second startup period.
</para>
- <section>
- <title>Radio Frequency</title>
- <para>
- The radio frequency is synthesized from a clock based on the 48 Mhz
- crystal on the board. The actual frequency of this oscillator must be
- measured to generate a calibration constant. While our GFSK modulation
- bandwidth is wide enough to allow boards to communicate even when
- their oscillators are not on exactly the same frequency, performance
- is best when they are closely matched.
- Radio frequency calibration requires a calibrated frequency counter.
- Fortunately, once set, the variation in frequency due to aging and
- temperature changes is small enough that re-calibration by customers
- should generally not be required.
- </para>
- <para>
- To calibrate the radio frequency, connect the UHF antenna port to a
- frequency counter, set the board to channel 0, and use the 'C'
- command to generate a CW carrier. Wait for the transmitter temperature
- to stabilize and the frequency to settle down.
- Then, divide 434.550 Mhz by the
- measured frequency and multiply by the current radio cal value show
- in the 'c s' command. For an unprogrammed board, the default value
- is 1186611. Take the resulting integer and program it using the 'c f'
- command. Testing with the 'C' command again should show a carrier
- within a few tens of Hertz of the intended frequency.
- As with all 'c' sub-commands, follow this with a 'c w' to write the
- change to the parameter block in the on-board DataFlash chip.
- </para>
- </section>
- <section>
- <title>Accelerometer</title>
- <para>
- The accelerometer we use has its own 5 volt power supply and
- the output must be passed through a resistive voltage divider to match
- the input of our 3.3 volt ADC. This means that unlike the barometric
- sensor, the output of the acceleration sensor is not ratiometric to
- the ADC converter, and calibration is required. We also support the
- use of any of several accelerometers from a Freescale family that
- includes at least +/- 40g, 50g, 100g, and 200g parts. Using gravity,
- a simple 2-point calibration yields acceptable results capturing both
- the different sensitivities and ranges of the different accelerometer
- parts and any variation in power supply voltages or resistor values
- in the divider network.
- </para>
- <para>
- To calibrate the acceleration sensor, use the 'c a 0' command. You
- will be prompted to orient the board vertically with the UHF antenna
- up and press a key, then to orient the board vertically with the
- UHF antenna down and press a key.
- As with all 'c' sub-commands, follow this with a 'c w' to write the
- change to the parameter block in the on-board DataFlash chip.
- </para>
- <para>
- The +1g and -1g calibration points are included in each telemetry
- frame and are part of the header extracted by ao-dumplog after flight.
- Note that we always store and return raw ADC samples for each
- sensor... nothing is permanently "lost" or "damaged" if the
- calibration is poor.
- </para>
- <para>
- In the unlikely event an accel cal that goes badly, it is possible
- that TeleMetrum may always come up in 'pad mode' and as such not be
- listening to either the USB or radio interfaces. If that happens,
- there is a special hook in the firmware to force the board back
- in to 'idle mode' so you can re-do the cal. To use this hook, you
- just need to ground the SPI clock pin at power-on. This pin is
- available as pin 2 on the 8-pin companion connector, and pin 1 is
- ground. So either carefully install a fine-gauge wire jumper
- between the two pins closest to the index hole end of the 8-pin
- connector, or plug in the programming cable to the 8-pin connector
- and use a small screwdriver or similar to short the two pins closest
- to the index post on the 4-pin end of the programming cable, and
- power up the board. It should come up in 'idle mode' (two beeps).
- </para>
- </section>
- </section>
-
-
-
- <section>
- <title>Updating Device Firmware</title>
- <para>
- The big conceptual thing to realize is that you have to use a
- TeleDongle as a programmer to update a TeleMetrum, and vice versa.
- Due to limited memory resources in the cc1111, we don't support
- programming either unit directly over USB.
- </para>
- <para>
- You may wish to begin by ensuring you have current firmware images.
- These are distributed as part of the AltOS software bundle that
- also includes the AltosUI ground station program. Newer ground
- station versions typically work fine with older firmware versions,
- so you don't need to update your devices just to try out new
- software features. You can always download the most recent
- version from <ulink url="http://www.altusmetrum.org/AltOS/"/>.
- </para>
- <para>
- We recommend updating TeleMetrum first, before updating TeleDongle.
- </para>
- <section>
- <title>Updating TeleMetrum Firmware</title>
- <orderedlist inheritnum='inherit' numeration='arabic'>
- <listitem>
- Find the 'programming cable' that you got as part of the starter
- kit, that has a red 8-pin MicroMaTch connector on one end and a
- red 4-pin MicroMaTch connector on the other end.
- </listitem>
- <listitem>
- Take the 2 screws out of the TeleDongle case to get access
- to the circuit board.
- </listitem>
- <listitem>
- Plug the 8-pin end of the programming cable to the
- matching connector on the TeleDongle, and the 4-pin end to the
- matching connector on the TeleMetrum.
- Note that each MicroMaTch connector has an alignment pin that
- goes through a hole in the PC board when you have the cable
- oriented correctly.
- </listitem>
- <listitem>
- Attach a battery to the TeleMetrum board.
- </listitem>
- <listitem>
- Plug the TeleDongle into your computer's USB port, and power
- up the TeleMetrum.
- </listitem>
- <listitem>
- Run AltosUI, and select 'Flash Image' from the File menu.
- </listitem>
- <listitem>
- Pick the TeleDongle device from the list, identifying it as the
- programming device.
- </listitem>
- <listitem>
- Select the image you want put on the TeleMetrum, which should have a
- name in the form telemetrum-v1.0-0.7.1.ihx. It should be visible
- in the default directory, if not you may have to poke around
- your system to find it.
- </listitem>
- <listitem>
- Make sure the configuration parameters are reasonable
- looking. If the serial number and/or RF configuration
- values aren't right, you'll need to change them.
- </listitem>
- <listitem>
- Hit the 'OK' button and the software should proceed to flash
- the TeleMetrum with new firmware, showing a progress bar.
- </listitem>
- <listitem>
- Confirm that the TeleMetrum board seems to have updated ok, which you
- can do by plugging in to it over USB and using a terminal program
- to connect to the board and issue the 'v' command to check
- the version, etc.
- </listitem>
- <listitem>
- If something goes wrong, give it another try.
- </listitem>
- </orderedlist>
</section>
<section>
- <title>Updating TeleDongle Firmware</title>
+ <title>GPS </title>
<para>
- Updating TeleDongle's firmware is just like updating TeleMetrum
- firmware, but you switch which board is the programmer and which
- is the programming target.
- </para>
- <orderedlist inheritnum='inherit' numeration='arabic'>
- <listitem>
- Find the 'programming cable' that you got as part of the starter
- kit, that has a red 8-pin MicroMaTch connector on one end and a
- red 4-pin MicroMaTch connector on the other end.
- </listitem>
- <listitem>
- Find the USB cable that you got as part of the starter kit, and
- plug the "mini" end in to the mating connector on TeleMetrum.
- </listitem>
- <listitem>
- Take the 2 screws out of the TeleDongle case to get access
- to the circuit board.
- </listitem>
- <listitem>
- Plug the 8-pin end of the programming cable to the (latching)
- matching connector on the TeleMetrum, and the 4-pin end to the
- matching connector on the TeleDongle.
- Note that each MicroMaTch connector has an alignment pin that
- goes through a hole in the PC board when you have the cable
- oriented correctly.
- </listitem>
- <listitem>
- Attach a battery to the TeleMetrum board.
- </listitem>
- <listitem>
- Plug both TeleMetrum and TeleDongle into your computer's USB
- ports, and power up the TeleMetrum.
- </listitem>
- <listitem>
- Run AltosUI, and select 'Flash Image' from the File menu.
- </listitem>
- <listitem>
- Pick the TeleMetrum device from the list, identifying it as the
- programming device.
- </listitem>
- <listitem>
- Select the image you want put on the TeleDongle, which should have a
- name in the form teledongle-v0.2-0.7.1.ihx. It should be visible
- in the default directory, if not you may have to poke around
- your system to find it.
- </listitem>
- <listitem>
- Make sure the configuration parameters are reasonable
- looking. If the serial number and/or RF configuration
- values aren't right, you'll need to change them. The TeleDongle
- serial number is on the "bottom" of the circuit board, and can
- usually be read through the translucent blue plastic case without
- needing to remove the board from the case.
- </listitem>
- <listitem>
- Hit the 'OK' button and the software should proceed to flash
- the TeleDongle with new firmware, showing a progress bar.
- </listitem>
- <listitem>
- Confirm that the TeleDongle board seems to have updated ok, which you
- can do by plugging in to it over USB and using a terminal program
- to connect to the board and issue the 'v' command to check
- the version, etc. Once you're happy, remove the programming cable
- and put the cover back on the TeleDongle.
- </listitem>
- <listitem>
- If something goes wrong, give it another try.
- </listitem>
- </orderedlist>
+ TeleMetrum and TeleMega include a complete GPS receiver. A
+ complete explanation of how GPS works is beyond the scope of
+ this manual, but the bottom line is that the GPS receiver
+ needs to lock onto at least four satellites to obtain a solid
+ 3 dimensional position fix and know what time it is.
+ </para>
<para>
- Be careful removing the programming cable from the locking 8-pin
- connector on TeleMetrum. You'll need a fingernail or perhaps a thin
- screwdriver or knife blade to gently pry the locking ears out
- slightly to extract the connector. We used a locking connector on
- TeleMetrum to help ensure that the cabling to companion boards
- used in a rocket don't ever come loose accidentally in flight.
+ The flight computers provide backup power to the GPS chip any time a
+ battery is connected. This allows the receiver to “warm start” on
+ the launch rail much faster than if every power-on were a GPS
+ “cold start”. In typical operations, powering up
+ on the flight line in idle mode while performing final air-frame
+ preparation will be sufficient to allow the GPS receiver to cold
+ start and acquire lock. Then the board can be powered down during
+ RSO review and installation on a launch rod or rail. When the board
+ is turned back on, the GPS system should lock very quickly, typically
+ long before igniter installation and return to the flight line are
+ complete.
</para>
</section>
- </section>
-
-
-
- </chapter>
- <chapter>
-
- <title>AltosUI</title>
- <para>
- The AltosUI program provides a graphical user interface for
- interacting with the Altus Metrum product family, including
- TeleMetrum and TeleDongle. AltosUI can monitor telemetry data,
- configure TeleMetrum and TeleDongle devices and many other
- tasks. The primary interface window provides a selection of
- buttons, one for each major activity in the system. This manual
- is split into chapters, each of which documents one of the tasks
- provided from the top-level toolbar.
- </para>
<section>
- <title>Packet Command Mode</title>
- <subtitle>Controlling TeleMetrum Over The Radio Link</subtitle>
+ <title>Controlling An Altimeter Over The Radio Link</title>
<para>
- One of the unique features of the Altus Metrum environment is
- the ability to create a two way command link between TeleDongle
- and TeleMetrum using the digital radio transceivers built into
- each device. This allows you to interact with TeleMetrum from
- afar, as if it were directly connected to the computer.
+ One of the unique features of the Altus Metrum system is the
+ ability to create a two way command link between TeleDongle
+ and an altimeter using the digital radio transceivers
+ built into each device. This allows you to interact with the
+ altimeter from afar, as if it were directly connected to the
+ computer.
</para>
<para>
- Any operation which can be performed with TeleMetrum
- can either be done with TeleMetrum directly connected to
- the computer via the USB cable, or through the packet
- link. Simply select the appropriate TeleDongle device when
- the list of devices is presented and AltosUI will use packet
- command mode.
+ Any operation which can be performed with a flight computer can
+ either be done with the device directly connected to the
+ computer via the USB cable, or through the radio
+ link. TeleMini v1.0 doesn't provide a USB connector and so it is
+ always communicated with over radio. Select the appropriate
+ TeleDongle device when the list of devices is presented and
+ AltosUI will interact with an altimeter over the radio link.
</para>
<para>
One oddity in the current interface is how AltosUI selects the
- channel for packet mode communications. Instead of providing
- an interface to specifically configure the channel, it uses
- whatever channel was most recently selected for the target
+ frequency for radio communications. Instead of providing
+ an interface to specifically configure the frequency, it uses
+ whatever frequency was most recently selected for the target
TeleDongle device in Monitor Flight mode. If you haven't ever
used that mode with the TeleDongle in question, select the
- Monitor Flight button from the top level UI, pick the
- appropriate TeleDongle device. Once the flight monitoring
- window is open, select the desired channel and then close it
- down again. All Packet Command Mode operations will now use
- that channel.
+ Monitor Flight button from the top level UI, and pick the
+ appropriate TeleDongle device. Once the flight monitoring
+ window is open, select the desired frequency and then close it
+ down again. All radio communications will now use that frequency.
</para>
<itemizedlist>
<listitem>
</listitem>
<listitem>
<para>
- Configure TeleMetrum—Reset apogee delays or main deploy
- heights to respond to changing launch conditions. You can
- also 'reboot' the TeleMetrum device. Use this to remotely
- enable the flight computer by turning TeleMetrum on while
- horizontal, then once the airframe is oriented for launch,
- you can reboot TeleMetrum and have it restart in pad mode
+ Configure altimeter apogee delays, main deploy heights
+ and additional pyro event conditions
+ to respond to changing launch conditions. You can also
+ 'reboot' the altimeter. Use this to remotely enable the
+ flight computer by turning TeleMetrum or TeleMega on in “idle” mode,
+ then once the air-frame is oriented for launch, you can
+ reboot the altimeter and have it restart in pad mode
without having to climb the scary ladder.
</para>
</listitem>
<listitem>
<para>
Fire Igniters—Test your deployment charges without snaking
- wires out through holes in the airframe. Simply assembly the
+ wires out through holes in the air-frame. Simply assemble the
rocket as if for flight with the apogee and main charges
- loaded, then remotely command TeleMetrum to fire the
+ loaded, then remotely command the altimeter to fire the
igniters.
</para>
</listitem>
</itemizedlist>
<para>
- Packet command mode uses the same RF channels as telemetry
- mode. Configure the desired TeleDongle channel using the
- flight monitor window channel selector and then close that
- window before performing the desired operation.
+ Operation over the radio link for configuring an altimeter, ground
+ testing igniters, and so forth uses the same RF frequencies as flight
+ telemetry. To configure the desired TeleDongle frequency, select
+ the monitor flight tab, then use the frequency selector and
+ close the window before performing other desired radio operations.
+ </para>
+ <para>
+ The flight computers only enable radio commanding in 'idle' mode.
+ TeleMetrum and TeleMega use the accelerometer to detect which orientation they
+ start up in, so make sure you have the flight computer lying horizontally when you turn
+ it on. Otherwise, it will start in 'pad' mode ready for
+ flight, and will not be listening for command packets from TeleDongle.
</para>
<para>
- TeleMetrum only enables packet command mode in 'idle' mode, so
- make sure you have TeleMetrum lying horizontally when you turn
- it on. Otherwise, TeleMetrum will start in 'pad' mode ready for
- flight and will not be listening for command packets from TeleDongle.
+ TeleMini listens for a command packet for five seconds after
+ first being turned on, if it doesn't hear anything, it enters
+ 'pad' mode, ready for flight and will no longer listen for
+ command packets. The easiest way to connect to TeleMini is to
+ initiate the command and select the TeleDongle device. At this
+ point, the TeleDongle will be attempting to communicate with
+ the TeleMini. Now turn TeleMini on, and it should immediately
+ start communicating with the TeleDongle and the desired
+ operation can be performed.
</para>
<para>
- When packet command mode is enabled, you can monitor the link
- by watching the lights on the TeleDongle and TeleMetrum
- devices. The red LED will flash each time TeleDongle or
- TeleMetrum transmit a packet while the green LED will light up
- on TeleDongle while it is waiting to receive a packet from
- TeleMetrum.
+ You can monitor the operation of the radio link by watching the
+ lights on the devices. The red LED will flash each time a packet
+ is transmitted, while the green LED will light up on TeleDongle when
+ it is waiting to receive a packet from the altimeter.
</para>
</section>
<section>
- <title>Monitor Flight</title>
- <subtitle>Receive, Record and Display Telemetry Data</subtitle>
+ <title>Ground Testing </title>
<para>
- Selecting this item brings up a dialog box listing all of the
- connected TeleDongle devices. When you choose one of these,
- AltosUI will create a window to display telemetry data as
- received by the selected TeleDongle device.
+ An important aspect of preparing a rocket using electronic deployment
+ for flight is ground testing the recovery system. Thanks
+ to the bi-directional radio link central to the Altus Metrum system,
+ this can be accomplished in a TeleMega, TeleMetrum or TeleMini equipped rocket
+ with less work than you may be accustomed to with other systems. It
+ can even be fun!
</para>
<para>
- All telemetry data received are automatically recorded in
- suitable log files. The name of the files includes the current
- date and rocket serial and flight numbers.
+ Just prep the rocket for flight, then power up the altimeter
+ in “idle” mode (placing air-frame horizontal for TeleMetrum or TeleMega, or
+ selecting the Configure Altimeter tab for TeleMini). This will cause
+ the firmware to go into “idle” mode, in which the normal flight
+ state machine is disabled and charges will not fire without
+ manual command. You can now command the altimeter to fire the apogee
+ or main charges from a safe distance using your computer and
+ TeleDongle and the Fire Igniter tab to complete ejection testing.
</para>
+ </section>
+ <section>
+ <title>Radio Link </title>
<para>
- The radio channel being monitored by the TeleDongle device is
- displayed at the top of the window. You can configure the
- channel by clicking on the channel box and selecting the desired
- channel. AltosUI remembers the last channel selected for each
- TeleDongle and selects that automatically the next time you use
- that device.
+ The chip our boards are based on incorporates an RF transceiver, but
+ it's not a full duplex system... each end can only be transmitting or
+ receiving at any given moment. So we had to decide how to manage the
+ link.
</para>
<para>
- Below the TeleDongle channel selector, the window contains a few
- significant pieces of information about the TeleMetrum providing
- the telemetry data stream:
- </para>
+ By design, the altimeter firmware listens for the radio link when
+ it's in “idle mode”, which
+ allows us to use the radio link to configure the rocket, do things like
+ ejection tests, and extract data after a flight without having to
+ crack open the air-frame. However, when the board is in “flight
+ mode”, the altimeter only
+ transmits and doesn't listen at all. That's because we want to put
+ ultimate priority on event detection and getting telemetry out of
+ the rocket through
+ the radio in case the rocket crashes and we aren't able to extract
+ data later...
+ </para>
+ <para>
+ We don't generally use a 'normal packet radio' mode like APRS
+ because they're just too inefficient. The GFSK modulation we
+ use is FSK with the base-band pulses passed through a Gaussian
+ filter before they go into the modulator to limit the
+ transmitted bandwidth. When combined with forward error
+ correction and interleaving, this allows us to have a very
+ robust 19.2 kilobit data link with only 10-40 milliwatts of
+ transmit power, a whip antenna in the rocket, and a hand-held
+ Yagi on the ground. We've had flights to above 21k feet AGL
+ with great reception, and calculations suggest we should be
+ good to well over 40k feet AGL with a 5-element yagi on the
+ ground with our 10mW units and over 100k feet AGL with the
+ 40mW devices. We hope to fly boards to higher altitudes over
+ time, and would of course appreciate customer feedback on
+ performance in higher altitude flights!
+ </para>
+ <para>
+ TeleMetrum v2.0 and TeleMega can send APRS if desired, the
+ interval between APRS packets can be configured. As each APRS
+ packet takes a full second to transmit, we recommend an
+ interval of at least 5 seconds to avoid consuming too much
+ battery power or radio channel bandwidth.
+ </para>
+ </section>
+ <section>
+ <title>Configurable Parameters</title>
+ <para>
+ Configuring an Altus Metrum altimeter for flight is very
+ simple. Even on our baro-only TeleMini and EasyMini boards, the use of a Kalman
+ filter means there is no need to set a “mach delay”. The few
+ configurable parameters can all be set using AltosUI over USB or
+ or radio link via TeleDongle.
+ </para>
+ <section>
+ <title>Radio Frequency</title>
+ <para>
+ Altus Metrum boards support radio frequencies in the 70cm
+ band. By default, the configuration interface provides a
+ list of 10 “standard” frequencies in 100kHz channels starting at
+ 434.550MHz. However, the firmware supports use of
+ any 50kHz multiple within the 70cm band. At any given
+ launch, we highly recommend coordinating when and by whom each
+ frequency will be used to avoid interference. And of course, both
+ altimeter and TeleDongle must be configured to the same
+ frequency to successfully communicate with each other.
+ </para>
+ </section>
+ <section>
+ <title>Apogee Delay</title>
+ <para>
+ Apogee delay is the number of seconds after the altimeter detects flight
+ apogee that the drogue charge should be fired. In most cases, this
+ should be left at the default of 0. However, if you are flying
+ redundant electronics such as for an L3 certification, you may wish
+ to set one of your altimeters to a positive delay so that both
+ primary and backup pyrotechnic charges do not fire simultaneously.
+ </para>
+ <para>
+ The Altus Metrum apogee detection algorithm fires exactly at
+ apogee. If you are also flying an altimeter like the
+ PerfectFlite MAWD, which only supports selecting 0 or 1
+ seconds of apogee delay, you may wish to set the MAWD to 0
+ seconds delay and set the TeleMetrum to fire your backup 2
+ or 3 seconds later to avoid any chance of both charges
+ firing simultaneously. We've flown several air-frames this
+ way quite happily, including Keith's successful L3 cert.
+ </para>
+ </section>
+ <section>
+ <title>Main Deployment Altitude</title>
+ <para>
+ By default, the altimeter will fire the main deployment charge at an
+ elevation of 250 meters (about 820 feet) above ground. We think this
+ is a good elevation for most air-frames, but feel free to change this
+ to suit. In particular, if you are flying two altimeters, you may
+ wish to set the
+ deployment elevation for the backup altimeter to be something lower
+ than the primary so that both pyrotechnic charges don't fire
+ simultaneously.
+ </para>
+ </section>
+ <section>
+ <title>Maximum Flight Log</title>
+ <para>
+ Changing this value will set the maximum amount of flight
+ log storage that an individual flight will use. The
+ available storage is divided into as many flights of the
+ specified size as can fit in the available space. You can
+ download and erase individual flight logs. If you fill up
+ the available storage, future flights will not get logged
+ until you erase some of the stored ones.
+ </para>
+ </section>
+ <section>
+ <title>Ignite Mode</title>
+ <para>
+ Instead of firing one charge at apogee and another charge at
+ a fixed height above the ground, you can configure the
+ altimeter to fire both at apogee or both during
+ descent. This was added to support an airframe that has two
+ altimeters, one in the fin can and one in the
+ nose.
+ </para>
+ <para>
+ Providing the ability to use both igniters for apogee or
+ main allows some level of redundancy without needing two
+ flight computers. In Redundant Apogee or Redundant Main
+ mode, the two charges will be fired two seconds apart.
+ </para>
+ </section>
+ <section>
+ <title>Pad Orientation</title>
+ <para>
+ TeleMetrum and TeleMega measure acceleration along the axis
+ of the board. Which way the board is oriented affects the
+ sign of the acceleration value. Instead of trying to guess
+ which way the board is mounted in the air frame, the
+ altimeter must be explicitly configured for either Antenna
+ Up or Antenna Down. The default, Antenna Up, expects the end
+ of the board connected to the 70cm antenna to be nearest the
+ nose of the rocket, with the end containing the screw
+ terminals nearest the tail.
+ </para>
+ </section>
+ <section>
+ <title>Pyro Channels</title>
+ <para>
+ In addition to the usual Apogee and Main pyro channels,
+ TeleMega has four additional channels that can be configured
+ to activate when various flight conditions are
+ satisfied. You can select as many conditions as necessary;
+ all of them must be met in order to activate the
+ channel. The conditions available are:
+ </para>
+ <itemizedlist>
+ <listitem>
+ <para>
+ Acceleration away from the ground. Select a value, and
+ then choose whether acceleration should be above or
+ below that value. Acceleration is positive upwards, so
+ accelerating towards the ground would produce negative
+ numbers. Acceleration during descent is noisy and
+ inaccurate, so be careful when using it during these
+ phases of the flight.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Vertical speed. Select a value, and then choose whether
+ vertical speed should be above or below that
+ value. Speed is positive upwards, so moving towards the
+ ground would produce negative numbers. Speed during
+ descent is a bit noisy and so be careful when using it
+ during these phases of the flight.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Height. Select a value, and then choose whether the
+ height above the launch pad should be above or below
+ that value.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Orientation. TeleMega contains a 3-axis gyroscope and
+ accelerometer which is used to measure the current
+ angle. Note that this angle is not the change in angle
+ from the launch pad, but rather absolute relative to
+ gravity; the 3-axis accelerometer is used to compute the
+ angle of the rocket on the launch pad and initialize the
+ system. Because this value is computed by integrating
+ rate gyros, it gets progressively less accurate as the
+ flight goes on. It should have an accumulated error of
+ less than .2°/second (after 10 seconds of flight, the
+ error should be less than 2°).
+ </para>
+ <para>
+ The usual use of the orientation configuration is to
+ ensure that the rocket is traveling mostly upwards when
+ deciding whether to ignite air starts or additional
+ stages. For that, choose a reasonable maximum angle
+ (like 20°) and set the motor igniter to require an angle
+ of less than that value.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Flight Time. Time since boost was detected. Select a
+ value and choose whether to activate the pyro channel
+ before or after that amount of time.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Ascending. A simple test saying whether the rocket is
+ going up or not. This is exactly equivalent to testing
+ whether the speed is > 0.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Descending. A simple test saying whether the rocket is
+ going down or not. This is exactly equivalent to testing
+ whether the speed is < 0.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ After Motor. The flight software counts each time the
+ rocket starts accelerating (presumably due to a motor or
+ motors igniting). Use this value to count ignitions for
+ multi-staged or multi-airstart launches.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Delay. This value doesn't perform any checks, instead it
+ inserts a delay between the time when the other
+ parameters become true and when the pyro channel is
+ activated.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Flight State. The flight software tracks the flight
+ through a sequence of states:
+ <orderedlist>
+ <listitem>
+ <para>
+ Boost. The motor has lit and the rocket is
+ accelerating upwards.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Fast. The motor has burned out and the rocket is
+ descellerating, but it is going faster than 200m/s.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Coast. The rocket is still moving upwards and
+ decelerating, but the speed is less than 200m/s.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Drogue. The rocket has reached apogee and is heading
+ back down, but is above the configured Main
+ altitude.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Main. The rocket is still descending, and is below
+ the Main altitude
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Landed. The rocket is no longer moving.
+ </para>
+ </listitem>
+ </orderedlist>
+ </para>
+ <para>
+ You can select a state to limit when the pyro channel
+ may activate; note that the check is based on when the
+ rocket transitions <emphasis>into</emphasis> the state, and so checking for
+ “greater than Boost” means that the rocket is currently
+ in boost or some later state.
+ </para>
+ <para>
+ When a motor burns out, the rocket enters either Fast or
+ Coast state (depending on how fast it is moving). If the
+ computer detects upwards acceleration again, it will
+ move back to Boost state.
+ </para>
+ </listitem>
+ </itemizedlist>
+ </section>
+ </section>
+
+ </chapter>
+ <chapter>
+
+ <title>AltosUI</title>
+ <para>
+ The AltosUI program provides a graphical user interface for
+ interacting with the Altus Metrum product family. AltosUI can
+ monitor telemetry data, configure devices and many other
+ tasks. The primary interface window provides a selection of
+ buttons, one for each major activity in the system. This manual
+ is split into chapters, each of which documents one of the tasks
+ provided from the top-level toolbar.
+ </para>
+ <section>
+ <title>Monitor Flight</title>
+ <subtitle>Receive, Record and Display Telemetry Data</subtitle>
+ <para>
+ Selecting this item brings up a dialog box listing all of the
+ connected TeleDongle devices. When you choose one of these,
+ AltosUI will create a window to display telemetry data as
+ received by the selected TeleDongle device.
+ </para>
+ <para>
+ All telemetry data received are automatically recorded in
+ suitable log files. The name of the files includes the current
+ date and rocket serial and flight numbers.
+ </para>
+ <para>
+ The radio frequency being monitored by the TeleDongle device is
+ displayed at the top of the window. You can configure the
+ frequency by clicking on the frequency box and selecting the desired
+ frequency. AltosUI remembers the last frequency selected for each
+ TeleDongle and selects that automatically the next time you use
+ that device.
+ </para>
+ <para>
+ Below the TeleDongle frequency selector, the window contains a few
+ significant pieces of information about the altimeter providing
+ the telemetry data stream:
+ </para>
<itemizedlist>
<listitem>
- <para>The TeleMetrum callsign</para>
+ <para>The configured call-sign</para>
</listitem>
<listitem>
- <para>The TeleMetrum serial number</para>
+ <para>The device serial number</para>
</listitem>
<listitem>
- <para>The flight number. Each TeleMetrum remembers how many
+ <para>The flight number. Each altimeter remembers how many
times it has flown.
</para>
</listitem>
The Received Signal Strength Indicator value. This lets
you know how strong a signal TeleDongle is receiving. The
radio inside TeleDongle operates down to about -99dBm;
- weaker signals may not be receiveable. The packet link uses
- error correction and detection techniques which prevent
+ weaker signals may not be receivable. The packet link uses
+ error detection and correction techniques which prevent
incorrect data from being reported.
</para>
</listitem>
+ <listitem>
+ <para>
+ The age of the displayed data, in seconds since the last
+ successfully received telemetry packet. In normal operation
+ this will stay in the low single digits. If the number starts
+ counting up, then you are no longer receiving data over the radio
+ link from the flight computer.
+ </para>
+ </listitem>
</itemizedlist>
<para>
Finally, the largest portion of the window contains a set of
They're arranged in 'flight order' so that as the flight
progresses, the selected tab automatically switches to display
data relevant to the current state of the flight. You can select
- other tabs at any time. The final 'table' tab contains all of
- the telemetry data in one place.
+ other tabs at any time. The final 'table' tab displays all of
+ the raw telemetry values in one place in a spreadsheet-like format.
</para>
<section>
<title>Launch Pad</title>
rocket is ready for flight. The first elements include red/green
indicators, if any of these is red, you'll want to evaluate
whether the rocket is ready to launch:
- <itemizedlist>
- <listitem>
- <para>
- Battery Voltage. This indicates whether the LiPo battery
- powering the TeleMetrum has sufficient charge to last for
- the duration of the flight. A value of more than
- 3.7V is required for a 'GO' status.
- </para>
- </listitem>
- <listitem>
- <para>
- Apogee Igniter Voltage. This indicates whether the apogee
- igniter has continuity. If the igniter has a low
- resistance, then the voltage measured here will be close
- to the LiPo battery voltage. A value greater than 3.2V is
- required for a 'GO' status.
- </para>
- </listitem>
- <listitem>
- <para>
- Main Igniter Voltage. This indicates whether the main
- igniter has continuity. If the igniter has a low
- resistance, then the voltage measured here will be close
- to the LiPo battery voltage. A value greater than 3.2V is
- required for a 'GO' status.
- </para>
- </listitem>
- <listitem>
- <para>
- GPS Locked. This indicates whether the GPS receiver is
- currently able to compute position information. GPS requires
- at least 4 satellites to compute an accurate position.
- </para>
- </listitem>
- <listitem>
- <para>
- GPS Ready. This indicates whether GPS has reported at least
- 10 consecutive positions without losing lock. This ensures
- that the GPS receiver has reliable reception from the
- satellites.
- </para>
- </listitem>
- </itemizedlist>
- <para>
- The LaunchPad tab also shows the computed launch pad position
- and altitude, averaging many reported positions to improve the
- accuracy of the fix.
- </para>
+ <variablelist>
+ <varlistentry>
+ <term>Battery Voltage</term>
+ <listitem>
+ <para>
+ This indicates whether the Li-Po battery
+ powering the TeleMetrum has sufficient charge to last for
+ the duration of the flight. A value of more than
+ 3.8V is required for a 'GO' status.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Apogee Igniter Voltage</term>
+ <listitem>
+ <para>
+ This indicates whether the apogee
+ igniter has continuity. If the igniter has a low
+ resistance, then the voltage measured here will be close
+ to the Li-Po battery voltage. A value greater than 3.2V is
+ required for a 'GO' status.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Main Igniter Voltage</term>
+ <listitem>
+ <para>
+ This indicates whether the main
+ igniter has continuity. If the igniter has a low
+ resistance, then the voltage measured here will be close
+ to the Li-Po battery voltage. A value greater than 3.2V is
+ required for a 'GO' status.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>On-board Data Logging</term>
+ <listitem>
+ <para>
+ This indicates whether there is
+ space remaining on-board to store flight data for the
+ upcoming flight. If you've downloaded data, but failed
+ to erase flights, there may not be any space
+ left. TeleMetrum can store multiple flights, depending
+ on the configured maximum flight log size. TeleMini
+ stores only a single flight, so it will need to be
+ downloaded and erased after each flight to capture
+ data. This only affects on-board flight logging; the
+ altimeter will still transmit telemetry and fire
+ ejection charges at the proper times.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>GPS Locked</term>
+ <listitem>
+ <para>
+ For a TeleMetrum or TeleMega device, this indicates whether the GPS receiver is
+ currently able to compute position information. GPS requires
+ at least 4 satellites to compute an accurate position.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>GPS Ready</term>
+ <listitem>
+ <para>
+ For a TeleMetrum or TeleMega device, this indicates whether GPS has reported at least
+ 10 consecutive positions without losing lock. This ensures
+ that the GPS receiver has reliable reception from the
+ satellites.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
</para>
+ <para>
+ The Launchpad tab also shows the computed launch pad position
+ and altitude, averaging many reported positions to improve the
+ accuracy of the fix.
+ </para>
</section>
<section>
<title>Ascent</title>
</para>
<para>
The height, speed and acceleration are shown along with the
- maxium values for each of them. This allows you to quickly
+ maximum values for each of them. This allows you to quickly
answer the most commonly asked questions you'll hear during
flight.
</para>
<para>
- The current latitude and longitude reported by the GPS are
+ The current latitude and longitude reported by the TeleMetrum GPS are
also shown. Note that under high acceleration, these values
may not get updated as the GPS receiver loses position
fix. Once the rocket starts coasting, the receiver should
<para>
To monitor whether the apogee charge operated correctly, the
current descent rate is reported along with the current
- height. Good descent rates generally range from 15-30m/s.
+ height. Good descent rates vary based on the choice of recovery
+ components, but generally range from 15-30m/s on drogue and should
+ be below 10m/s when under the main parachute in a dual-deploy flight.
</para>
<para>
- To help locate the rocket in the sky, use the elevation and
- bearing information to figure out where to look. Elevation is
- in degrees above the horizon. Bearing is reported in degrees
- relative to true north. Range can help figure out how big the
- rocket will appear. Note that all of these values are relative
- to the pad location. If the elevation is near 90°, the rocket
- is over the pad, not over you.
+ For TeleMetrum altimeters, you can locate the rocket in the
+ sky using the elevation and bearing information to figure
+ out where to look. Elevation is in degrees above the
+ horizon. Bearing is reported in degrees relative to true
+ north. Range can help figure out how big the rocket will
+ appear. Ground Distance shows how far it is to a point
+ directly under the rocket and can help figure out where the
+ rocket is likely to land. Note that all of these values are
+ relative to the pad location. If the elevation is near 90°,
+ the rocket is over the pad, not over you.
</para>
<para>
Finally, the igniter voltages are reported in this tab as
well, both to monitor the main charge as well as to see what
- the status of the apogee charge is.
+ the status of the apogee charge is. Note that some commercial
+ e-matches are designed to retain continuity even after being
+ fired, and will continue to show as green or return from red to
+ green after firing.
</para>
</section>
<section>
<title>Landed</title>
<para>
Once the rocket is on the ground, attention switches to
- recovery. While the radio signal is generally lost once the
+ recovery. While the radio signal is often lost once the
rocket is on the ground, the last reported GPS position is
generally within a short distance of the actual landing location.
</para>
The last reported GPS position is reported both by
latitude and longitude as well as a bearing and distance from
the launch pad. The distance should give you a good idea of
- whether you'll want to walk or hitch a ride. Take the reported
- latitude and longitude and enter them into your handheld GPS
+ whether to walk or hitch a ride. Take the reported
+ latitude and longitude and enter them into your hand-held GPS
unit and have that compute a track to the landing location.
</para>
+ <para>
+ Both TeleMini and TeleMetrum will continue to transmit RDF
+ tones after landing, allowing you to locate the rocket by
+ following the radio signal if necessary. You may need to get
+ away from the clutter of the flight line, or even get up on
+ a hill (or your neighbor's RV roof) to receive the RDF signal.
+ </para>
<para>
- Finally, the maximum height, speed and acceleration reported
+ The maximum height, speed and acceleration reported
during the flight are displayed for your admiring observers.
+ The accuracy of these immediate values depends on the quality
+ of your radio link and how many packets were received.
+ Recovering the on-board data after flight will likely yield
+ more precise results.
</para>
+ <para>
+ To get more detailed information about the flight, you can
+ click on the 'Graph Flight' button which will bring up a
+ graph window for the current flight.
+ </para>
</section>
<section>
<title>Site Map</title>
<para>
- When the rocket gets a GPS fix, the Site Map tab will map
+ When the TeleMetrum has a GPS fix, the Site Map tab will map
the rocket's position to make it easier for you to locate the
rocket, both while it is in the air, and when it has landed. The
- rocket's state is indicated by colour: white for pad, red for
+ rocket's state is indicated by color: white for pad, red for
boost, pink for fast, yellow for coast, light blue for drogue,
dark blue for main, and black for landed.
</para>
<para>
The map's scale is approximately 3m (10ft) per pixel. The map
can be dragged using the left mouse button. The map will attempt
- to keep the rocket roughly centred while data is being received.
+ to keep the rocket roughly centered while data is being received.
</para>
<para>
Images are fetched automatically via the Google Maps Static API,
- and are cached for reuse. If map images cannot be downloaded,
- the rocket's path will be traced on a dark grey background
+ and cached on disk for reuse. If map images cannot be downloaded,
+ the rocket's path will be traced on a dark gray background
instead.
</para>
+ <para>
+ You can pre-load images for your favorite launch sites
+ before you leave home; check out the 'Preload Maps' section below.
+ </para>
</section>
</section>
<section>
<title>Save Flight Data</title>
<para>
- TeleMetrum records flight data to its internal flash memory.
- This data is recorded at a much higher rate than the telemetry
+ The altimeter records flight data to its internal flash memory.
+ TeleMetrum data is recorded at a much higher rate than the telemetry
system can handle, and is not subject to radio drop-outs. As
such, it provides a more complete and precise record of the
flight. The 'Save Flight Data' button allows you to read the
- flash memory and write it to disk.
+ flash memory and write it to disk. As TeleMini has only a barometer, it
+ records data at the same rate as the telemetry signal, but there will be
+ no data lost due to telemetry drop-outs.
</para>
<para>
Clicking on the 'Save Flight Data' button brings up a list of
connected TeleMetrum and TeleDongle devices. If you select a
TeleMetrum device, the flight data will be downloaded from that
device directly. If you select a TeleDongle device, flight data
- will be downloaded from a TeleMetrum device connected via the
- packet command link to the specified TeleDongle. See the chapter
- on Packet Command Mode for more information about this.
+ will be downloaded from an altimeter over radio link via the
+ specified TeleDongle. See the chapter on Controlling An Altimeter
+ Over The Radio Link for more information.
</para>
<para>
After the device has been selected, a dialog showing the
select which flights to download and which to delete. With
version 0.9 or newer firmware, you must erase flights in order
for the space they consume to be reused by another
- flight. This prevents you from accidentally losing flight data
+ flight. This prevents accidentally losing flight data
if you neglect to download data before flying again. Note that
if there is no more space available in the device, then no
- data will be recorded for a flight.
+ data will be recorded during the next flight.
</para>
<para>
- The filename for each flight log is computed automatically
- from the recorded flight date, TeleMetrum serial number and
+ The file name for each flight log is computed automatically
+ from the recorded flight date, altimeter serial number and
flight number information.
</para>
</section>
<para>
Select this button and you are prompted to select a flight
record file, either a .telem file recording telemetry data or a
- .eeprom file containing flight data saved from the TeleMetrum
+ .eeprom file containing flight data saved from the altimeter
flash memory.
</para>
<para>
<para>
Select this button and you are prompted to select a flight
record file, either a .telem file recording telemetry data or a
- .eeprom file containing flight data saved from the TeleMetrum
+ .eeprom file containing flight data saved from
flash memory.
</para>
<para>
- Once a flight record is selected, the acceleration (blue),
- velocity (green) and altitude (red) of the flight are plotted and
- displayed, measured in metric units.
+ Once a flight record is selected, a window with multiple tabs is
+ opened.
+ <variablelist>
+ <varlistentry>
+ <term>Flight Graph</term>
+ <listitem>
+ <para>
+ By default, the graph contains acceleration (blue),
+ velocity (green) and altitude (red).
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Configure Graph</term>
+ <listitem>
+ <para>
+ This selects which graph elements to show, and, at the
+ very bottom, lets you switch between metric and
+ imperial units
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Flight Statistics</term>
+ <listitem>
+ <para>
+ Shows overall data computed from the flight.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Map</term>
+ <listitem>
+ <para>
+ Shows a satellite image of the flight area overlaid
+ with the path of the flight. The red concentric
+ circles mark the launch pad, the black concentric
+ circles mark the landing location.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
</para>
<para>
The graph can be zoomed into a particular area by clicking and
dragging down and to the right. Once zoomed, the graph can be
reset by clicking and dragging up and to the left. Holding down
control and clicking and dragging allows the graph to be panned.
- The right mouse button causes a popup menu to be displayed, giving
+ The right mouse button causes a pop-up menu to be displayed, giving
you the option save or print the plot.
</para>
<para>
Note that telemetry files will generally produce poor graphs
- due to the lower sampling rate and missed telemetry packets,
- and will also often have significant amounts of data received
- while the rocket was waiting on the pad. Use saved flight data
- for graphing where possible.
+ due to the lower sampling rate and missed telemetry packets.
+ Use saved flight data in .eeprom files for graphing where possible.
</para>
</section>
<section>
<title>Export Data</title>
<para>
This tool takes the raw data files and makes them available for
- external analysis. When you select this button, you are prompted to select a flight
+ external analysis. When you select this button, you are prompted to
+ select a flight
data file (either .eeprom or .telem will do, remember that
.eeprom files contain higher resolution and more continuous
data). Next, a second dialog appears which is used to select
This is a text file containing the data in a form suitable for
import into a spreadsheet or other external data analysis
tool. The first few lines of the file contain the version and
- configuration information from the TeleMetrum device, then
+ configuration information from the altimeter, then
there is a single header line which labels all of the
fields. All of these lines start with a '#' character which
- most tools can be configured to skip over.
+ many tools can be configured to skip over.
</para>
<para>
The remaining lines of the file contain the data, with each
<section>
<title>Keyhole Markup Language (for Google Earth)</title>
<para>
- This is the format used by
- Googleearth to provide an overlay within that
- application. With this, you can use Googleearth to see the
- whole flight path in 3D.
+ This is the format used by Google Earth to provide an overlay
+ within that application. With this, you can use Google Earth to
+ see the whole flight path in 3D.
</para>
</section>
</section>
<section>
- <title>Configure TeleMetrum</title>
+ <title>Configure Altimeter</title>
<para>
- Select this button and then select either a TeleMetrum or
+ Select this button and then select either an altimeter or
TeleDongle Device from the list provided. Selecting a TeleDongle
- device will use Packet Comamnd Mode to configure remote
- TeleMetrum device. Learn how to use this in the Packet Command
- Mode chapter.
+ device will use the radio link to configure a remote altimeter.
</para>
<para>
The first few lines of the dialog provide information about the
- connected TeleMetrum device, including the product name,
+ connected device, including the product name,
software version and hardware serial number. Below that are the
individual configuration entries.
</para>
<para>
At the bottom of the dialog, there are four buttons:
</para>
- <itemizedlist>
- <listitem>
- <para>
- Save. This writes any changes to the TeleMetrum
- configuration parameter block in flash memory. If you don't
- press this button, any changes you make will be lost.
- </para>
- </listitem>
- <listitem>
- <para>
- Reset. This resets the dialog to the most recently saved values,
- erasing any changes you have made.
- </para>
- </listitem>
- <listitem>
- <para>
- Reboot. This reboots the TeleMetrum device. Use this to
- switch from idle to pad mode by rebooting once the rocket is
- oriented for flight.
- </para>
- </listitem>
- <listitem>
- <para>
- Close. This closes the dialog. Any unsaved changes will be
- lost.
- </para>
- </listitem>
- </itemizedlist>
+ <variablelist>
+ <varlistentry>
+ <term>Save</term>
+ <listitem>
+ <para>
+ This writes any changes to the
+ configuration parameter block in flash memory. If you don't
+ press this button, any changes you make will be lost.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Reset</term>
+ <listitem>
+ <para>
+ This resets the dialog to the most recently saved values,
+ erasing any changes you have made.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Reboot</term>
+ <listitem>
+ <para>
+ This reboots the device. Use this to
+ switch from idle to pad mode by rebooting once the rocket is
+ oriented for flight, or to confirm changes you think you saved
+ are really saved.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Close</term>
+ <listitem>
+ <para>
+ This closes the dialog. Any unsaved changes will be
+ lost.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
<para>
The rest of the dialog contains the parameters to be configured.
</para>
<para>
When flying redundant electronics, it's often important to
ensure that multiple apogee charges don't fire at precisely
- the same time as that can overpressurize the apogee deployment
- bay and cause a structural failure of the airframe. The Apogee
+ the same time, as that can over pressurize the apogee deployment
+ bay and cause a structural failure of the air-frame. The Apogee
Delay parameter tells the flight computer to fire the apogee
charge a certain number of seconds after apogee has been
detected.
</para>
</section>
<section>
- <title>Radio Channel</title>
+ <title>Radio Frequency</title>
<para>
- This configures which of the 10 radio channels to use for both
+ This configures which of the frequencies to use for both
telemetry and packet command mode. Note that if you set this
- value via packet command mode, you will have to reconfigure
- the TeleDongle channel before you will be able to use packet
- command mode again.
+ value via packet command mode, the TeleDongle frequency will
+ also be automatically reconfigured to match so that
+ communication will continue afterwards.
</para>
</section>
<section>
- <title>Radio Calibration</title>
+ <title>RF Calibration</title>
<para>
The radios in every Altus Metrum device are calibrated at the
factory to ensure that they transmit and receive on the
- specified frequency for each channel. You can adjust that
- calibration by changing this value. To change the TeleDongle's
- calibration, you must reprogram the unit completely.
+ specified frequency. If you need to you can adjust the calibration
+ by changing this value. Do not do this without understanding what
+ the value means, read the appendix on calibration and/or the source
+ code for more information. To change a TeleDongle's calibration,
+ you must reprogram the unit completely.
</para>
</section>
+ <section>
+ <title>Telemetry/RDF/APRS Enable</title>
+ <para>
+ Enables the radio for transmission during flight. When
+ disabled, the radio will not transmit anything during flight
+ at all.
+ </para>
+ </section>
+ <section>
+ <title>APRS Interval</title>
+ <para>
+ How often to transmit GPS information via APRS. This option
+ is available on TeleMetrum v2 and TeleMega
+ boards. TeleMetrum v1 boards cannot transmit APRS
+ packets. Note that a single APRS packet takes nearly a full
+ second to transmit, so enabling this option will prevent
+ sending any other telemetry during that time.
+ </para>
+ </section>
<section>
<title>Callsign</title>
<para>
- This sets the callsign included in each telemetry packet. Set this
+ This sets the call sign included in each telemetry packet. Set this
as needed to conform to your local radio regulations.
</para>
</section>
size. A smaller value will allow more flights to be stored,
a larger value will record data from longer flights.
</para>
+ </section>
+ <section>
+ <title>Ignite Mode</title>
<para>
- During ascent, TeleMetrum records barometer and
- accelerometer values 100 times per second, other analog
- information (voltages and temperature) 6 times per second
- and GPS data once per second. During descent, the non-GPS
- data is recorded 1/10th as often. Each barometer +
- accelerometer record takes 8 bytes.
+ TeleMetrum and TeleMini provide two igniter channels as they
+ were originally designed as dual-deploy flight
+ computers. This configuration parameter allows the two
+ channels to be used in different configurations.
</para>
+ <variablelist>
+ <varlistentry>
+ <term>Dual Deploy</term>
+ <listitem>
+ <para>
+ This is the usual mode of operation; the
+ 'apogee' channel is fired at apogee and the 'main'
+ channel at the height above ground specified by the
+ 'Main Deploy Altitude' during descent.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Redundant Apogee</term>
+ <listitem>
+ <para>
+ This fires both channels at
+ apogee, the 'apogee' channel first followed after a two second
+ delay by the 'main' channel.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Redundant Main</term>
+ <listitem>
+ <para>
+ This fires both channels at the
+ height above ground specified by the Main Deploy
+ Altitude setting during descent. The 'apogee'
+ channel is fired first, followed after a two second
+ delay by the 'main' channel.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </section>
+ <section>
+ <title>Pad Orientation</title>
<para>
- The default, 192kB, will store over 200 seconds of data at
- the ascent rate, or over 2000 seconds of data at the descent
- rate. That's plenty for most flights. This leaves enough
- storage for five flights in a 1MB system, or 10 flights in a
- 2MB system.
+ Because it includes an accelerometer, TeleMetrum and
+ TeleMega are sensitive to the orientation of the board. By
+ default, it expects the antenna end to point forward. This
+ parameter allows that default to be changed, permitting the
+ board to be mounted with the antenna pointing aft instead.
</para>
+ <variablelist>
+ <varlistentry>
+ <term>Antenna Up</term>
+ <listitem>
+ <para>
+ In this mode, the antenna end of the
+ TeleMetrum board must point forward, in line with the
+ expected flight path.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Antenna Down</term>
+ <listitem>
+ <para>
+ In this mode, the antenna end of the
+ TeleMetrum board must point aft, in line with the
+ expected flight path.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </section>
+ <section>
+ <title>Configure Pyro Channels</title>
<para>
- The configuration block takes the last available block of
- memory, on v1.0 boards that's just 256 bytes. However, the
- flash part on the v1.1 boards uses 64kB for each block.
- </para>
+ This opens a separate window to configure the additional
+ pyro channels available on TeleMega. One column is
+ presented for each channel. Each row represents a single
+ parameter, if enabled the parameter must meet the specified
+ test for the pyro channel to be fired. See the Pyro Channels
+ section in the System Operation chapter above for a
+ description of these parameters.
+ </para>
+ <para>
+ Select conditions and set the related value; the pyro
+ channel will be activated when <emphasis>all</emphasis> of the
+ conditions are met. Each pyro channel has a separate set of
+ configuration values, so you can use different values for
+ the same condition with different channels.
+ </para>
+ <para>
+ Once you have selected the appropriate configuration for all
+ of the necessary pyro channels, you can save the pyro
+ configuration along with the rest of the flight computer
+ configuration by pressing the 'Save' button in the main
+ Configure Flight Computer window.
+ </para>
</section>
</section>
<section>
<section>
<title>Voice Settings</title>
<para>
- AltosUI provides voice annoucements during flight so that you
+ AltosUI provides voice announcements during flight so that you
can keep your eyes on the sky and still get information about
the current flight status. However, sometimes you don't want
to hear them.
<listitem>
<para>
Test Voice—Plays a short message allowing you to verify
- that the audio systme is working and the volume settings
+ that the audio system is working and the volume settings
are reasonable
</para>
</listitem>
<section>
<title>Callsign</title>
<para>
- This value is used in command packet mode and is transmitted
- in each packet sent from TeleDongle and received from
- TeleMetrum. It is not used in telemetry mode as that transmits
- packets only from TeleMetrum to TeleDongle. Configure this
- with the AltosUI operators callsign as needed to comply with
+ This value is transmitted in each command packet sent from
+ TeleDongle and received from an altimeter. It is not used in
+ telemetry mode, as the callsign configured in the altimeter board
+ is included in all telemetry packets. Configure this
+ with the AltosUI operators call sign as needed to comply with
your local radio regulations.
</para>
+ <para>
+ Note that to successfully command a flight computer over the radio
+ (to configure the altimeter, monitor idle, or fire pyro charges),
+ the callsign configured here must exactly match the callsign
+ configured in the flight computer. This matching is case
+ sensitive.
+ </para>
+ </section>
+ <section>
+ <title>Imperial Units</title>
+ <para>
+ This switches between metric units (meters) and imperial
+ units (feet and miles). This affects the display of values
+ use during flight monitoring, configuration, data graphing
+ and all of the voice announcements. It does not change the
+ units used when exporting to CSV files, those are always
+ produced in metric units.
+ </para>
+ </section>
+ <section>
+ <title>Font Size</title>
+ <para>
+ Selects the set of fonts used in the flight monitor
+ window. Choose between the small, medium and large sets.
+ </para>
</section>
<section>
<title>Serial Debug</title>
various serial communication issues.
</para>
</section>
+ <section>
+ <title>Manage Frequencies</title>
+ <para>
+ This brings up a dialog where you can configure the set of
+ frequencies shown in the various frequency menus. You can
+ add as many as you like, or even reconfigure the default
+ set. Changing this list does not affect the frequency
+ settings of any devices, it only changes the set of
+ frequencies shown in the menus.
+ </para>
+ </section>
+ </section>
+ <section>
+ <title>Configure Groundstation</title>
+ <para>
+ Select this button and then select a TeleDongle Device from the list provided.
+ </para>
+ <para>
+ The first few lines of the dialog provide information about the
+ connected device, including the product name,
+ software version and hardware serial number. Below that are the
+ individual configuration entries.
+ </para>
+ <para>
+ Note that the TeleDongle itself doesn't save any configuration
+ data, the settings here are recorded on the local machine in
+ the Java preferences database. Moving the TeleDongle to
+ another machine, or using a different user account on the same
+ machine will cause settings made here to have no effect.
+ </para>
+ <para>
+ At the bottom of the dialog, there are three buttons:
+ </para>
+ <variablelist>
+ <varlistentry>
+ <term>Save</term>
+ <listitem>
+ <para>
+ This writes any changes to the
+ local Java preferences file. If you don't
+ press this button, any changes you make will be lost.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Reset</term>
+ <listitem>
+ <para>
+ This resets the dialog to the most recently saved values,
+ erasing any changes you have made.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Close</term>
+ <listitem>
+ <para>
+ This closes the dialog. Any unsaved changes will be
+ lost.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ <para>
+ The rest of the dialog contains the parameters to be configured.
+ </para>
+ <section>
+ <title>Frequency</title>
+ <para>
+ This configures the frequency to use for both telemetry and
+ packet command mode. Set this before starting any operation
+ involving packet command mode so that it will use the right
+ frequency. Telemetry monitoring mode also provides a menu to
+ change the frequency, and that menu also sets the same Java
+ preference value used here.
+ </para>
+ </section>
+ <section>
+ <title>Radio Calibration</title>
+ <para>
+ The radios in every Altus Metrum device are calibrated at the
+ factory to ensure that they transmit and receive on the
+ specified frequency. To change a TeleDongle's calibration,
+ you must reprogram the unit completely, so this entry simply
+ shows the current value and doesn't allow any changes.
+ </para>
+ </section>
</section>
<section>
<title>Flash Image</title>
<para>
- This reprograms any Altus Metrum device by using a TeleMetrum or
- TeleDongle as a programming dongle. Please read the directions
- for connecting the programming cable in the main TeleMetrum
- manual before reading these instructions.
+ This reprograms Altus Metrum device with new
+ firmware. TeleMetrum v1.x, TeleDongle, TeleMini and TeleBT are
+ all reprogrammed by using another similar unit as a
+ programming dongle (pair programming). TeleMega, TeleMetrum v2
+ and EasyMini are all programmed directly over their USB ports
+ (self programming). Please read the directions for flashing
+ devices in the Updating Device Firmware chapter below.
+ </para>
+ <para>
+ For “self programming”, connect USB to the device to be
+ programmed and push the 'Flash Image' button. That will
+ present a dialog box listing all of the connected
+ devices. Carefully select the device to be programmed.
</para>
<para>
- Once you have the programmer and target devices connected,
- push the 'Flash Image' button. That will present a dialog box
- listing all of the connected devices. Carefully select the
- programmer device, not the device to be programmed.
+ For “pair programming”, once you have the programmer and
+ target devices connected, push the 'Flash Image' button. That
+ will present a dialog box listing all of the connected
+ devices. Carefully select the programmer device, not the
+ device to be programmed.
</para>
<para>
Next, select the image to flash to the device. These are named
</para>
<para>
When programming is complete, the target device will
- reboot. Note that if the target device is connected via USB, you
- will have to unplug it and then plug it back in for the USB
- connection to reset so that you can communicate with the device
- again.
+ reboot. Note that if a pair programmed target device is
+ connected via USB, you will have to unplug it and then plug it
+ back in for the USB connection to reset so that you can
+ communicate with the device again.
</para>
</section>
<section>
recovery systems deployment. Because this command can operate
over the Packet Command Link, you can prepare the rocket as
for flight and then test the recovery system without needing
- to snake wires inside the airframe.
+ to snake wires inside the air-frame.
</para>
<para>
Selecting the 'Fire Igniter' button brings up the usual device
selection dialog. Pick the desired TeleDongle or TeleMetrum
device. This brings up another window which shows the current
- continutity test status for both apogee and main charges.
+ continuity test status for both apogee and main charges.
</para>
<para>
Next, select the desired igniter to fire. This will enable the
selecting the desired igniter.
</para>
</section>
+ <section>
+ <title>Scan Channels</title>
+ <para>
+ This listens for telemetry packets on all of the configured
+ frequencies, displaying information about each device it
+ receives a packet from. You can select which of the three
+ telemetry formats should be tried; by default, it only listens
+ for the standard telemetry packets used in v1.0 and later
+ firmware.
+ </para>
+ </section>
+ <section>
+ <title>Load Maps</title>
+ <para>
+ Before heading out to a new launch site, you can use this to
+ load satellite images in case you don't have internet
+ connectivity at the site. This loads a fairly large area
+ around the launch site, which should cover any flight you're likely to make.
+ </para>
+ <para>
+ There's a drop-down menu of launch sites we know about; if
+ your favorites aren't there, please let us know the lat/lon
+ and name of the site. The contents of this list are actually
+ downloaded at run-time, so as new sites are sent in, they'll
+ get automatically added to this list.
+ </para>
+ <para>
+ If the launch site isn't in the list, you can manually enter the lat/lon values
+ </para>
+ <para>
+ Clicking the 'Load Map' button will fetch images from Google
+ Maps; note that Google limits how many images you can fetch at
+ once, so if you load more than one launch site, you may get
+ some gray areas in the map which indicate that Google is tired
+ of sending data to you. Try again later.
+ </para>
+ </section>
+ <section>
+ <title>Monitor Idle</title>
+ <para>
+ This brings up a dialog similar to the Monitor Flight UI,
+ except it works with the altimeter in “idle” mode by sending
+ query commands to discover the current state rather than
+ listening for telemetry packets. Because this uses command
+ mode, it needs to have the TeleDongle and flight computer
+ callsigns match exactly. If you can receive telemetry, but
+ cannot manage to run Monitor Idle, then it's very likely that
+ your callsigns are different in some way.
+ </para>
+ </section>
</chapter>
<chapter>
- <title>Using Altus Metrum Products</title>
+ <title>AltosDroid</title>
+ <para>
+ AltosDroid provides the same flight monitoring capabilities as
+ AltosUI, but runs on Android devices and is designed to connect
+ to a TeleBT receiver over Bluetooth™. Altos Droid monitors
+ telemetry data, logging it to internal storage in the Android
+ device, and presents that data in a UI the same way the 'Monitor
+ Flight' window does in AltosUI.
+ </para>
+ <para>
+ This manual will explain how to configure AltosDroid, connect
+ to TeleBT, operate the flight monitoring interface and describe
+ what the displayed data means.
+ </para>
<section>
- <title>Being Legal</title>
+ <title>Installing AltosDroid</title>
<para>
- First off, in the US, you need an <ulink url="http://www.altusmetrum.org/Radio/">amateur radio license</ulink> or
- other authorization to legally operate the radio transmitters that are part
- of our products.
+ AltosDroid is included in the Google Play store. To install
+ it on your Android device, open open the Google Play Store
+ application and search for “altosdroid”. Make sure you don't
+ have a space between “altos” and “droid” or you probably won't
+ find what you want. That should bring you to the right page
+ from which you can download and install the application.
+ </para>
+ </section>
+ <section>
+ <title>Connecting to TeleBT</title>
+ <para>
+ Press the Android 'Menu' button or soft-key to see the
+ configuration options available. Select the 'Connect a device'
+ option and then the 'Scan for devices' entry at the bottom to
+ look for your TeleBT device. Select your device, and when it
+ asks for the code, enter '1234'.
+ </para>
+ <para>
+ Subsequent connections will not require you to enter that
+ code, and your 'paired' device will appear in the list without
+ scanning.
+ </para>
+ </section>
+ <section>
+ <title>Configuring AltosDroid</title>
+ <para>
+ The only configuration option available for AltosDroid is
+ which frequency to listen on. Press the Android 'Menu' button
+ or soft-key and pick the 'Select radio frequency' entry. That
+ brings up a menu of pre-set radio frequencies; pick the one
+ which matches your altimeter.
+ </para>
+ </section>
+ <section>
+ <title>Altos Droid Flight Monitoring</title>
+ <para>
+ Altos Droid is designed to mimic the AltosUI flight monitoring
+ display, providing separate tabs for each stage of your rocket
+ flight along with a tab containing a map of the local area
+ with icons marking the current location of the altimeter and
+ the Android device.
</para>
- </section>
<section>
- <title>In the Rocket</title>
- <para>
- In the rocket itself, you just need a <ulink url="http://www.altusmetrum.org/TeleMetrum/">TeleMetrum</ulink> board and
- a LiPo rechargeable battery. An 860mAh battery weighs less than a 9V
- alkaline battery, and will run a <ulink url="http://www.altusmetrum.org/TeleMetrum/">TeleMetrum</ulink> for hours.
- </para>
+ <title>Pad</title>
<para>
- By default, we ship TeleMetrum with a simple wire antenna. If your
- electronics bay or the airframe it resides within is made of carbon fiber,
- which is opaque to RF signals, you may choose to have an SMA connector
- installed so that you can run a coaxial cable to an antenna mounted
- elsewhere in the rocket.
- </para>
+ The 'Launch Pad' tab shows information used to decide when the
+ rocket is ready for flight. The first elements include red/green
+ indicators, if any of these is red, you'll want to evaluate
+ whether the rocket is ready to launch:
+ <variablelist>
+ <varlistentry>
+ <term>Battery Voltage</term>
+ <listitem>
+ <para>
+ This indicates whether the Li-Po battery
+ powering the TeleMetrum has sufficient charge to last for
+ the duration of the flight. A value of more than
+ 3.8V is required for a 'GO' status.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Apogee Igniter Voltage</term>
+ <listitem>
+ <para>
+ This indicates whether the apogee
+ igniter has continuity. If the igniter has a low
+ resistance, then the voltage measured here will be close
+ to the Li-Po battery voltage. A value greater than 3.2V is
+ required for a 'GO' status.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>Main Igniter Voltage</term>
+ <listitem>
+ <para>
+ This indicates whether the main
+ igniter has continuity. If the igniter has a low
+ resistance, then the voltage measured here will be close
+ to the Li-Po battery voltage. A value greater than 3.2V is
+ required for a 'GO' status.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>On-board Data Logging</term>
+ <listitem>
+ <para>
+ This indicates whether there is
+ space remaining on-board to store flight data for the
+ upcoming flight. If you've downloaded data, but failed
+ to erase flights, there may not be any space
+ left. TeleMetrum can store multiple flights, depending
+ on the configured maximum flight log size. TeleMini
+ stores only a single flight, so it will need to be
+ downloaded and erased after each flight to capture
+ data. This only affects on-board flight logging; the
+ altimeter will still transmit telemetry and fire
+ ejection charges at the proper times.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>GPS Locked</term>
+ <listitem>
+ <para>
+ For a TeleMetrum or TeleMega device, this indicates whether the GPS receiver is
+ currently able to compute position information. GPS requires
+ at least 4 satellites to compute an accurate position.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>GPS Ready</term>
+ <listitem>
+ <para>
+ For a TeleMetrum or TeleMega device, this indicates whether GPS has reported at least
+ 10 consecutive positions without losing lock. This ensures
+ that the GPS receiver has reliable reception from the
+ satellites.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </para>
+ <para>
+ The Launchpad tab also shows the computed launch pad position
+ and altitude, averaging many reported positions to improve the
+ accuracy of the fix.
+ </para>
+ </section>
+ </section>
+ <section>
+ <title>Downloading Flight Logs</title>
+ <para>
+ Altos Droid always saves every bit of telemetry data it
+ receives. To download that to a computer for use with AltosUI,
+ simply remove the SD card from your Android device, or connect
+ your device to your computer's USB port and browse the files
+ on that device. You will find '.telem' files in the TeleMetrum
+ directory that will work with AltosUI directly.
+ </para>
+ </section>
+ </chapter>
+ <chapter>
+ <title>Using Altus Metrum Products</title>
+ <section>
+ <title>Being Legal</title>
+ <para>
+ First off, in the US, you need an <ulink url="http://www.altusmetrum.org/Radio/">amateur radio license</ulink> or
+ other authorization to legally operate the radio transmitters that are part
+ of our products.
+ </para>
+ </section>
+ <section>
+ <title>In the Rocket</title>
+ <para>
+ In the rocket itself, you just need a <ulink url="http://www.altusmetrum.org/TeleMetrum/">TeleMetrum</ulink> or
+ <ulink url="http://www.altusmetrum.org/TeleMini/">TeleMini</ulink> board and
+ a single-cell, 3.7 volt nominal Li-Po rechargeable battery. An
+ 850mAh battery weighs less than a 9V alkaline battery, and will
+ run a TeleMetrum for hours.
+ A 110mAh battery weighs less than a triple A battery and will run a TeleMetrum for
+ a few hours, or a TeleMini for much (much) longer.
+ </para>
+ <para>
+ By default, we ship the altimeters with a simple wire antenna. If your
+ electronics bay or the air-frame it resides within is made of carbon fiber,
+ which is opaque to RF signals, you may choose to have an SMA connector
+ installed so that you can run a coaxial cable to an antenna mounted
+ elsewhere in the rocket.
+ </para>
</section>
<section>
<title>On the Ground</title>
<para>
To receive the data stream from the rocket, you need an antenna and short
- feedline connected to one of our <ulink url="http://www.altusmetrum.org/TeleDongle/">TeleDongle</ulink> units. The
+ feed-line connected to one of our <ulink url="http://www.altusmetrum.org/TeleDongle/">TeleDongle</ulink> units. If possible, use an SMA to BNC
+ adapter instead of feedline between the antenna feedpoint and
+ TeleDongle, as this will give you the best performance. The
TeleDongle in turn plugs directly into the USB port on a notebook
computer. Because TeleDongle looks like a simple serial port, your computer
does not require special device drivers... just plug it in.
for Linux which can perform most of the same tasks.
</para>
<para>
- After the flight, you can use the RF link to extract the more detailed data
- logged in the rocket, or you can use a mini USB cable to plug into the
+ After the flight, you can use the radio link to extract the more detailed data
+ logged in either TeleMetrum or TeleMini devices, or you can use a mini USB cable to plug into the
TeleMetrum board directly. Pulling out the data without having to open up
- the rocket is pretty cool! A USB cable is also how you charge the LiPo
+ the rocket is pretty cool! A USB cable is also how you charge the Li-Po
battery, so you'll want one of those anyway... the same cable used by lots
of digital cameras and other modern electronic stuff will work fine.
</para>
<para>
- If your rocket lands out of sight, you may enjoy having a hand-held GPS
- receiver, so that you can put in a waypoint for the last reported rocket
+ If your TeleMetrum-equipped rocket lands out of sight, you may enjoy having a hand-held GPS
+ receiver, so that you can put in a way-point for the last reported rocket
position before touch-down. This makes looking for your rocket a lot like
- Geo-Cacheing... just go to the waypoint and look around starting from there.
+ Geo-Caching... just go to the way-point and look around starting from there.
</para>
<para>
- You may also enjoy having a ham radio "HT" that covers the 70cm band... you
+ You may also enjoy having a ham radio “HT” that covers the 70cm band... you
can use that with your antenna to direction-find the rocket on the ground
the same way you can use a Walston or Beeline tracker. This can be handy
if the rocket is hiding in sage brush or a tree, or if the last GPS position
doesn't get you close enough because the rocket dropped into a canyon, or
the wind is blowing it across a dry lake bed, or something like that... Keith
- and Bdale both currently own and use the Yaesu VX-7R at launches.
+ currently uses a Yaesu VX-7R, Bdale has a Baofung UV-5R
+ which isn't as nice, but was a whole lot cheaper.
</para>
<para>
So, to recap, on the ground the hardware you'll need includes:
<orderedlist inheritnum='inherit' numeration='arabic'>
<listitem>
- an antenna and feedline
+ <para>
+ an antenna and feed-line or adapter
+ </para>
</listitem>
<listitem>
- a TeleDongle
+ <para>
+ a TeleDongle
+ </para>
</listitem>
<listitem>
- a notebook computer
+ <para>
+ a notebook computer
+ </para>
</listitem>
<listitem>
- optionally, a handheld GPS receiver
+ <para>
+ optionally, a hand-held GPS receiver
+ </para>
</listitem>
<listitem>
- optionally, an HT or receiver covering 435 Mhz
+ <para>
+ optionally, an HT or receiver covering 435 MHz
+ </para>
</listitem>
</orderedlist>
</para>
Arrow Antennas.
</ulink>
The 440-3 and 440-5 are both good choices for finding a
- TeleMetrum-equipped rocket when used with a suitable 70cm HT.
+ TeleMetrum- or TeleMini- equipped rocket when used with a suitable
+ 70cm HT. TeleDongle and an SMA to BNC adapter fit perfectly
+ between the driven element and reflector of Arrow antennas.
</para>
</section>
<section>
<title>Data Analysis</title>
<para>
Our software makes it easy to log the data from each flight, both the
- telemetry received over the RF link during the flight itself, and the more
- complete data log recorded in the DataFlash memory on the TeleMetrum
- board. Once this data is on your computer, our postflight tools make it
+ telemetry received during the flight itself, and the more
+ complete data log recorded in the flash memory on the altimeter
+ board. Once this data is on your computer, our post-flight tools make it
easy to quickly get to the numbers everyone wants, like apogee altitude,
max acceleration, and max velocity. You can also generate and view a
standard set of plots showing the altitude, acceleration, and
- velocity of the rocket during flight. And you can even export a data file
- useable with Google Maps and Google Earth for visualizing the flight path
+ velocity of the rocket during flight. And you can even export a TeleMetrum data file
+ usable with Google Maps and Google Earth for visualizing the flight path
in two or three dimensions!
</para>
<para>
<section>
<title>Future Plans</title>
<para>
- In the future, we intend to offer "companion boards" for the rocket that will
- plug in to TeleMetrum to collect additional data, provide more pyro channels,
- and so forth. A reference design for a companion board will be documented
- soon, and will be compatible with open source Arduino programming tools.
+ In the future, we intend to offer “companion boards” for the rocket
+ that will plug in to TeleMetrum to collect additional data, provide
+ more pyro channels, and so forth.
+ </para>
+ <para>
+ Also under design is a new flight computer with more sensors, more
+ pyro channels, and a more powerful radio system designed for use
+ in multi-stage, complex, and extreme altitude projects.
</para>
<para>
- We are also working on the design of a hand-held ground terminal that will
- allow monitoring the rocket's status, collecting data during flight, and
- logging data after flight without the need for a notebook computer on the
- flight line. Particularly since it is so difficult to read most notebook
- screens in direct sunlight, we think this will be a great thing to have.
+ We are also working on alternatives to TeleDongle. One is a
+ a stand-alone, hand-held ground terminal that will allow monitoring
+ the rocket's status, collecting data during flight, and logging data
+ after flight without the need for a notebook computer on the
+ flight line. Particularly since it is so difficult to read most
+ notebook screens in direct sunlight, we think this will be a great
+ thing to have. We are also working on a TeleDongle variant with
+ Bluetooth that will work with Android phones and tablets.
</para>
<para>
- Because all of our work is open, both the hardware designs and the software,
- if you have some great idea for an addition to the current Altus Metrum family,
- feel free to dive in and help! Or let us know what you'd like to see that
- we aren't already working on, and maybe we'll get excited about it too...
+ Because all of our work is open, both the hardware designs and the
+ software, if you have some great idea for an addition to the current
+ Altus Metrum family, feel free to dive in and help! Or let us know
+ what you'd like to see that we aren't already working on, and maybe
+ we'll get excited about it too...
+ </para>
+ <para>
+ Watch our
+ <ulink url="http://altusmetrum.org/">web site</ulink> for more news
+ and information as our family of products evolves!
</para>
</section>
</chapter>
-</book>
+ <chapter>
+ <title>Altimeter Installation Recommendations</title>
+ <para>
+ Building high-power rockets that fly safely is hard enough. Mix
+ in some sophisticated electronics and a bunch of radio energy
+ and oftentimes you find few perfect solutions. This chapter
+ contains some suggestions about how to install Altus Metrum
+ products into the rocket air-frame, including how to safely and
+ reliably mix a variety of electronics into the same air-frame.
+ </para>
+ <section>
+ <title>Mounting the Altimeter</title>
+ <para>
+ The first consideration is to ensure that the altimeter is
+ securely fastened to the air-frame. For TeleMetrum, we use
+ nylon standoffs and nylon screws; they're good to at least 50G
+ and cannot cause any electrical issues on the board. For
+ TeleMini, we usually cut small pieces of 1/16 inch balsa to fit
+ under the screw holes, and then take 2x56 nylon screws and
+ screw them through the TeleMini mounting holes, through the
+ balsa and into the underlying material.
+ </para>
+ <orderedlist inheritnum='inherit' numeration='arabic'>
+ <listitem>
+ <para>
+ Make sure TeleMetrum is aligned precisely along the axis of
+ acceleration so that the accelerometer can accurately
+ capture data during the flight.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Watch for any metal touching components on the
+ board. Shorting out connections on the bottom of the board
+ can cause the altimeter to fail during flight.
+ </para>
+ </listitem>
+ </orderedlist>
+ </section>
+ <section>
+ <title>Dealing with the Antenna</title>
+ <para>
+ The antenna supplied is just a piece of solid, insulated,
+ wire. If it gets damaged or broken, it can be easily
+ replaced. It should be kept straight and not cut; bending or
+ cutting it will change the resonant frequency and/or
+ impedance, making it a less efficient radiator and thus
+ reducing the range of the telemetry signal.
+ </para>
+ <para>
+ Keeping metal away from the antenna will provide better range
+ and a more even radiation pattern. In most rockets, it's not
+ entirely possible to isolate the antenna from metal
+ components; there are often bolts, all-thread and wires from other
+ electronics to contend with. Just be aware that the more stuff
+ like this around the antenna, the lower the range.
+ </para>
+ <para>
+ Make sure the antenna is not inside a tube made or covered
+ with conducting material. Carbon fiber is the most common
+ culprit here -- CF is a good conductor and will effectively
+ shield the antenna, dramatically reducing signal strength and
+ range. Metallic flake paint is another effective shielding
+ material which is to be avoided around any antennas.
+ </para>
+ <para>
+ If the ebay is large enough, it can be convenient to simply
+ mount the altimeter at one end and stretch the antenna out
+ inside. Taping the antenna to the sled can keep it straight
+ under acceleration. If there are metal rods, keep the
+ antenna as far away as possible.
+ </para>
+ <para>
+ For a shorter ebay, it's quite practical to have the antenna
+ run through a bulkhead and into an adjacent bay. Drill a small
+ hole in the bulkhead, pass the antenna wire through it and
+ then seal it up with glue or clay. We've also used acrylic
+ tubing to create a cavity for the antenna wire. This works a
+ bit better in that the antenna is known to stay straight and
+ not get folded by recovery components in the bay. Angle the
+ tubing towards the side wall of the rocket and it ends up
+ consuming very little space.
+ </para>
+ <para>
+ If you need to place the antenna at a distance from the
+ altimeter, you can replace the antenna with an edge-mounted
+ SMA connector, and then run 50Ω coax from the board to the
+ antenna. Building a remote antenna is beyond the scope of this
+ manual.
+ </para>
+ </section>
+ <section>
+ <title>Preserving GPS Reception</title>
+ <para>
+ The GPS antenna and receiver in TeleMetrum are highly
+ sensitive and normally have no trouble tracking enough
+ satellites to provide accurate position information for
+ recovering the rocket. However, there are many ways to
+ attenuate the GPS signal.
+ <orderedlist inheritnum='inherit' numeration='arabic'>
+ <listitem>
+ <para>
+ Conductive tubing or coatings. Carbon fiber and metal
+ tubing, or metallic paint will all dramatically attenuate the
+ GPS signal. We've never heard of anyone successfully
+ receiving GPS from inside these materials.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Metal components near the GPS patch antenna. These will
+ de-tune the patch antenna, changing the resonant frequency
+ away from the L1 carrier and reduce the effectiveness of the
+ antenna. You can place as much stuff as you like beneath the
+ antenna as that's covered with a ground plane. But, keep
+ wires and metal out from above the patch antenna.
+ </para>
+ </listitem>
+ </orderedlist>
+ </para>
+ </section>
+ <section>
+ <title>Radio Frequency Interference</title>
+ <para>
+ Any altimeter will generate RFI; the digital circuits use
+ high-frequency clocks that spray radio interference across a
+ wide band. Altus Metrum altimeters generate intentional radio
+ signals as well, increasing the amount of RF energy around the board.
+ </para>
+ <para>
+ Rocketry altimeters also use precise sensors measuring air
+ pressure and acceleration. Tiny changes in voltage can cause
+ these sensor readings to vary by a huge amount. When the
+ sensors start mis-reporting data, the altimeter can either
+ fire the igniters at the wrong time, or not fire them at all.
+ </para>
+ <para>
+ Voltages are induced when radio frequency energy is
+ transmitted from one circuit to another. Here are things that
+ influence the induced voltage and current:
+ </para>
+ <itemizedlist>
+ <listitem>
+ <para>
+ Keep wires from different circuits apart. Moving circuits
+ further apart will reduce RFI.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Avoid parallel wires from different circuits. The longer two
+ wires run parallel to one another, the larger the amount of
+ transferred energy. Cross wires at right angles to reduce
+ RFI.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Twist wires from the same circuits. Two wires the same
+ distance from the transmitter will get the same amount of
+ induced energy which will then cancel out. Any time you have
+ a wire pair running together, twist the pair together to
+ even out distances and reduce RFI. For altimeters, this
+ includes battery leads, switch hookups and igniter
+ circuits.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Avoid resonant lengths. Know what frequencies are present
+ in the environment and avoid having wire lengths near a
+ natural resonant length. Altusmetrum products transmit on the
+ 70cm amateur band, so you should avoid lengths that are a
+ simple ratio of that length; essentially any multiple of ¼
+ of the wavelength (17.5cm).
+ </para>
+ </listitem>
+ </itemizedlist>
+ </section>
+ <section>
+ <title>The Barometric Sensor</title>
+ <para>
+ Altusmetrum altimeters measure altitude with a barometric
+ sensor, essentially measuring the amount of air above the
+ rocket to figure out how high it is. A large number of
+ measurements are taken as the altimeter initializes itself to
+ figure out the pad altitude. Subsequent measurements are then
+ used to compute the height above the pad.
+ </para>
+ <para>
+ To accurately measure atmospheric pressure, the ebay
+ containing the altimeter must be vented outside the
+ air-frame. The vent must be placed in a region of linear
+ airflow, have smooth edges, and away from areas of increasing or
+ decreasing pressure.
+ </para>
+ <para>
+ The barometric sensor in the altimeter is quite sensitive to
+ chemical damage from the products of APCP or BP combustion, so
+ make sure the ebay is carefully sealed from any compartment
+ which contains ejection charges or motors.
+ </para>
+ </section>
+ <section>
+ <title>Ground Testing</title>
+ <para>
+ The most important aspect of any installation is careful
+ ground testing. Bringing an air-frame up to the LCO table which
+ hasn't been ground tested can lead to delays or ejection
+ charges firing on the pad, or, even worse, a recovery system
+ failure.
+ </para>
+ <para>
+ Do a 'full systems' test that includes wiring up all igniters
+ without any BP and turning on all of the electronics in flight
+ mode. This will catch any mistakes in wiring and any residual
+ RFI issues that might accidentally fire igniters at the wrong
+ time. Let the air-frame sit for several minutes, checking for
+ adequate telemetry signal strength and GPS lock. If any igniters
+ fire unexpectedly, find and resolve the issue before loading any
+ BP charges!
+ </para>
+ <para>
+ Ground test the ejection charges. Prepare the rocket for
+ flight, loading ejection charges and igniters. Completely
+ assemble the air-frame and then use the 'Fire Igniters'
+ interface through a TeleDongle to command each charge to
+ fire. Make sure the charge is sufficient to robustly separate
+ the air-frame and deploy the recovery system.
+ </para>
+ </section>
+ </chapter>
+ <chapter>
+ <title>Updating Device Firmware</title>
+ <para>
+ TeleMega, TeleMetrum v2 and EasyMini are all programmed directly
+ over their USB connectors (self programming). TeleMetrum v1, TeleMini and
+ TeleDongle are all programmed by using another device as a
+ programmer (pair programming). It's important to recognize which
+ kind of devices you have before trying to reprogram them.
+ </para>
+ <para>
+ You may wish to begin by ensuring you have current firmware images.
+ These are distributed as part of the AltOS software bundle that
+ also includes the AltosUI ground station program. Newer ground
+ station versions typically work fine with older firmware versions,
+ so you don't need to update your devices just to try out new
+ software features. You can always download the most recent
+ version from <ulink url="http://www.altusmetrum.org/AltOS/"/>.
+ </para>
+ <para>
+ We recommend updating the altimeter first, before updating TeleDongle.
+ </para>
+ <para>
+ Self-programmable devices (TeleMega, TeleMetrum v2 and EasyMini)
+ are reprogrammed by connecting them to your computer over USB
+ </para>
+ <section>
+ <title>
+ Updating TeleMega, TeleMetrum v2 or EasyMini Firmware
+ </title>
+ <orderedlist inheritnum='inherit' numeration='arabic'>
+ <listitem>
+ <para>
+ Attach a battery and power switch to the target
+ device. Power up the device.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Using a Micro USB cable, connect the target device to your
+ computer's USB socket.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Run AltosUI, and select 'Flash Image' from the File menu.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Select the target device in the Device Selection dialog.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Select the image you want to flash to the device, which
+ should have a name in the form
+ <product>-v<product-version>-<software-version>.ihx, such
+ as TeleMega-v1.0-1.3.0.ihx.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Make sure the configuration parameters are reasonable
+ looking. If the serial number and/or RF configuration
+ values aren't right, you'll need to change them.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Hit the 'OK' button and the software should proceed to flash
+ the device with new firmware, showing a progress bar.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Verify that the device is working by using the 'Configure
+ Altimeter' item to check over the configuration.
+ </para>
+ </listitem>
+ </orderedlist>
+ <section>
+ <title>Recovering From Self-Flashing Failure</title>
+ <para>
+ If the firmware loading fails, it can leave the device
+ unable to boot. Not to worry, you can force the device to
+ start the boot loader instead, which will let you try to
+ flash the device again.
+ </para>
+ <para>
+ On each device, connecting two pins from one of the exposed
+ connectors will force the boot loader to start, even if the
+ regular operating system has been corrupted in some way.
+ </para>
+ <variablelist>
+ <varlistentry>
+ <term>TeleMega</term>
+ <listitem>
+ <para>
+ Connect pin 6 and pin 1 of the companion connector. Pin 1
+ can be identified by the square pad around it, and then
+ the pins could sequentially across the board. Be very
+ careful to <emphasis>not</emphasis> short pin 8 to
+ anything as that is connected directly to the battery. Pin
+ 7 carries 3.3V and the board will crash if that is
+ connected to pin 1, but shouldn't damage the board.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>TeleMetrum v2</term>
+ <listitem>
+ <para>
+ Connect pin 6 and pin 1 of the companion connector. Pin 1
+ can be identified by the square pad around it, and then
+ the pins could sequentially across the board. Be very
+ careful to <emphasis>not</emphasis> short pin 8 to
+ anything as that is connected directly to the battery. Pin
+ 7 carries 3.3V and the board will crash if that is
+ connected to pin 1, but shouldn't damage the board.
+ </para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term>EasyMini</term>
+ <listitem>
+ <para>
+ Connect pin 6 and pin 1 of the debug connector, which is
+ the six holes next to the beeper. Pin 1 can be identified
+ by the square pad around it, and then the pins could
+ sequentially across the board, making Pin 6 the one on the
+ other end of the row.
+ </para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </section>
+ </section>
+ <section>
+ <title>Pair Programming</title>
+ <para>
+ The big concept to understand is that you have to use a
+ TeleMega, TeleMetrum or TeleDongle as a programmer to update a
+ pair programmed device. Due to limited memory resources in the
+ cc1111, we don't support programming directly over USB for these
+ devices.
+ </para>
+ </section>
+ <section>
+ <title>Updating TeleMetrum v1.x Firmware</title>
+ <orderedlist inheritnum='inherit' numeration='arabic'>
+ <listitem>
+ <para>
+ Find the 'programming cable' that you got as part of the starter
+ kit, that has a red 8-pin MicroMaTch connector on one end and a
+ red 4-pin MicroMaTch connector on the other end.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Take the 2 screws out of the TeleDongle case to get access
+ to the circuit board.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Plug the 8-pin end of the programming cable to the
+ matching connector on the TeleDongle, and the 4-pin end to the
+ matching connector on the TeleMetrum.
+ Note that each MicroMaTch connector has an alignment pin that
+ goes through a hole in the PC board when you have the cable
+ oriented correctly.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Attach a battery to the TeleMetrum board.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Plug the TeleDongle into your computer's USB port, and power
+ up the TeleMetrum.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Run AltosUI, and select 'Flash Image' from the File menu.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Pick the TeleDongle device from the list, identifying it as the
+ programming device.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Select the image you want put on the TeleMetrum, which should have a
+ name in the form telemetrum-v1.2-1.0.0.ihx. It should be visible
+ in the default directory, if not you may have to poke around
+ your system to find it.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Make sure the configuration parameters are reasonable
+ looking. If the serial number and/or RF configuration
+ values aren't right, you'll need to change them.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Hit the 'OK' button and the software should proceed to flash
+ the TeleMetrum with new firmware, showing a progress bar.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Confirm that the TeleMetrum board seems to have updated OK, which you
+ can do by plugging in to it over USB and using a terminal program
+ to connect to the board and issue the 'v' command to check
+ the version, etc.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ If something goes wrong, give it another try.
+ </para>
+ </listitem>
+ </orderedlist>
+ </section>
+ <section>
+ <title>Updating TeleMini Firmware</title>
+ <orderedlist inheritnum='inherit' numeration='arabic'>
+ <listitem>
+<para>
+ You'll need a special 'programming cable' to reprogram the
+ TeleMini. It's available on the Altus Metrum web store, or
+ you can make your own using an 8-pin MicroMaTch connector on
+ one end and a set of four pins on the other.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Take the 2 screws out of the TeleDongle case to get access
+ to the circuit board.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Plug the 8-pin end of the programming cable to the matching
+ connector on the TeleDongle, and the 4-pins into the holes
+ in the TeleMini circuit board. Note that the MicroMaTch
+ connector has an alignment pin that goes through a hole in
+ the PC board when you have the cable oriented correctly, and
+ that pin 1 on the TeleMini board is marked with a square pad
+ while the other pins have round pads.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Attach a battery to the TeleMini board.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Plug the TeleDongle into your computer's USB port, and power
+ up the TeleMini
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Run AltosUI, and select 'Flash Image' from the File menu.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Pick the TeleDongle device from the list, identifying it as the
+ programming device.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Select the image you want put on the TeleMini, which should have a
+ name in the form telemini-v1.0-1.0.0.ihx. It should be visible
+ in the default directory, if not you may have to poke around
+ your system to find it.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Make sure the configuration parameters are reasonable
+ looking. If the serial number and/or RF configuration
+ values aren't right, you'll need to change them.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Hit the 'OK' button and the software should proceed to flash
+ the TeleMini with new firmware, showing a progress bar.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Confirm that the TeleMini board seems to have updated OK, which you
+ can do by configuring it over the radio link through the TeleDongle, or
+ letting it come up in “flight” mode and listening for telemetry.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ If something goes wrong, give it another try.
+ </para>
+</listitem>
+ </orderedlist>
+ </section>
+ <section>
+ <title>Updating TeleDongle Firmware</title>
+ <para>
+ Updating TeleDongle's firmware is just like updating TeleMetrum or TeleMini
+ firmware, but you use either a TeleMetrum or another TeleDongle as the programmer.
+ </para>
+ <orderedlist inheritnum='inherit' numeration='arabic'>
+ <listitem>
+<para>
+ Find the 'programming cable' that you got as part of the starter
+ kit, that has a red 8-pin MicroMaTch connector on one end and a
+ red 4-pin MicroMaTch connector on the other end.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Find the USB cable that you got as part of the starter kit, and
+ plug the “mini” end in to the mating connector on TeleMetrum or TeleDongle.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Take the 2 screws out of the TeleDongle case to get access
+ to the circuit board.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Plug the 8-pin end of the programming cable to the
+ matching connector on the programmer, and the 4-pin end to the
+ matching connector on the TeleDongle.
+ Note that each MicroMaTch connector has an alignment pin that
+ goes through a hole in the PC board when you have the cable
+ oriented correctly.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Attach a battery to the TeleMetrum board if you're using one.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Plug both the programmer and the TeleDongle into your computer's USB
+ ports, and power up the programmer.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Run AltosUI, and select 'Flash Image' from the File menu.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Pick the programmer device from the list, identifying it as the
+ programming device.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Select the image you want put on the TeleDongle, which should have a
+ name in the form teledongle-v0.2-1.0.0.ihx. It should be visible
+ in the default directory, if not you may have to poke around
+ your system to find it.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Make sure the configuration parameters are reasonable
+ looking. If the serial number and/or RF configuration
+ values aren't right, you'll need to change them. The TeleDongle
+ serial number is on the “bottom” of the circuit board, and can
+ usually be read through the translucent blue plastic case without
+ needing to remove the board from the case.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Hit the 'OK' button and the software should proceed to flash
+ the TeleDongle with new firmware, showing a progress bar.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ Confirm that the TeleDongle board seems to have updated OK, which you
+ can do by plugging in to it over USB and using a terminal program
+ to connect to the board and issue the 'v' command to check
+ the version, etc. Once you're happy, remove the programming cable
+ and put the cover back on the TeleDongle.
+ </para>
+</listitem>
+ <listitem>
+<para>
+ If something goes wrong, give it another try.
+ </para>
+</listitem>
+ </orderedlist>
+ <para>
+ Be careful removing the programming cable from the locking 8-pin
+ connector on TeleMetrum. You'll need a fingernail or perhaps a thin
+ screwdriver or knife blade to gently pry the locking ears out
+ slightly to extract the connector. We used a locking connector on
+ TeleMetrum to help ensure that the cabling to companion boards
+ used in a rocket don't ever come loose accidentally in flight.
+ </para>
+ </section>
+ </chapter>
+ <chapter>
+ <title>Hardware Specifications</title>
+ <section>
+ <title>
+ TeleMega Specifications
+ </title>
+ <itemizedlist>
+ <listitem>
+ <para>
+ Recording altimeter for model rocketry.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Supports dual deployment and four auxiliary pyro channels
+ (a total of 6 events).
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ 70cm 40mW ham-band transceiver for telemetry down-link.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Barometric pressure sensor good to 100k feet MSL.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ 1-axis high-g accelerometer for motor characterization, capable of
+ +/- 102g.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ 9-axis IMU including integrated 3-axis accelerometer,
+ 3-axis gyroscope and 3-axis magnetometer.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ On-board, integrated uBlox Max 7 GPS receiver with 5Hz update rate capability.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ On-board 8 Megabyte non-volatile memory for flight data storage.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ USB interface for battery charging, configuration, and data recovery.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Fully integrated support for Li-Po rechargeable batteries.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Uses Li-Po to fire e-matches, can be modified to support
+ optional separate pyro battery if needed.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ 3.25 x 1.25 inch board designed to fit inside 38mm air-frame coupler tube.
+ </para>
+ </listitem>
+ </itemizedlist>
+ </section>
+ <section>
+ <title>
+ TeleMetrum v2 Specifications
+ </title>
+ <itemizedlist>
+ <listitem>
+ <para>
+ Recording altimeter for model rocketry.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Supports dual deployment (can fire 2 ejection charges).
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ 70cm, 40mW ham-band transceiver for telemetry down-link.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Barometric pressure sensor good to 100k feet MSL.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ 1-axis high-g accelerometer for motor characterization, capable of
+ +/- 102g.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ On-board, integrated uBlox Max 7 GPS receiver with 5Hz update rate capability.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ On-board 8 Megabyte non-volatile memory for flight data storage.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ USB interface for battery charging, configuration, and data recovery.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Fully integrated support for Li-Po rechargeable batteries.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Uses Li-Po to fire e-matches, can be modified to support
+ optional separate pyro battery if needed.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ 2.75 x 1 inch board designed to fit inside 29mm air-frame coupler tube.
+ </para>
+ </listitem>
+ </itemizedlist>
+ </section>
+ <section>
+ <title>TeleMetrum v1 Specifications</title>
+ <itemizedlist>
+ <listitem>
+ <para>
+ Recording altimeter for model rocketry.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Supports dual deployment (can fire 2 ejection charges).
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ 70cm, 10mW ham-band transceiver for telemetry down-link.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Barometric pressure sensor good to 45k feet MSL.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ 1-axis high-g accelerometer for motor characterization, capable of
+ +/- 50g using default part.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ On-board, integrated GPS receiver with 5Hz update rate capability.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ On-board 1 megabyte non-volatile memory for flight data storage.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ USB interface for battery charging, configuration, and data recovery.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Fully integrated support for Li-Po rechargeable batteries.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Uses Li-Po to fire e-matches, can be modified to support
+ optional separate pyro battery if needed.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ 2.75 x 1 inch board designed to fit inside 29mm air-frame coupler tube.
+ </para>
+ </listitem>
+ </itemizedlist>
+ </section>
+ <section>
+ <title>
+ TeleMini v2.0 Specifications
+ </title>
+ <itemizedlist>
+ <listitem>
+ <para>
+ Recording altimeter for model rocketry.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Supports dual deployment (can fire 2 ejection charges).
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ 70cm, 10mW ham-band transceiver for telemetry down-link.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Barometric pressure sensor good to 100k feet MSL.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ On-board 1 megabyte non-volatile memory for flight data storage.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ USB interface for configuration, and data recovery.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Support for Li-Po rechargeable batteries (using an
+ external charger), or any 3.7-15V external battery.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Uses Li-Po to fire e-matches, can be modified to support
+ optional separate pyro battery if needed.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ 1.5 x .8 inch board designed to fit inside 24mm air-frame coupler tube.
+ </para>
+ </listitem>
+ </itemizedlist>
+ </section>
+ <section>
+ <title>
+ TeleMini v1.0 Specifications
+ </title>
+ <itemizedlist>
+ <listitem>
+ <para>
+ Recording altimeter for model rocketry.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Supports dual deployment (can fire 2 ejection charges).
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ 70cm, 10mW ham-band transceiver for telemetry down-link.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Barometric pressure sensor good to 45k feet MSL.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ On-board 5 kilobyte non-volatile memory for flight data storage.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ RF interface for configuration, and data recovery.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Support for Li-Po rechargeable batteries, using an external charger.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Uses Li-Po to fire e-matches, can be modified to support
+ optional separate pyro battery if needed.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ 1.5 x .5 inch board designed to fit inside 18mm air-frame coupler tube.
+ </para>
+ </listitem>
+ </itemizedlist>
+ </section>
+ <section>
+ <title>
+ EasyMini Specifications
+ </title>
+ <itemizedlist>
+ <listitem>
+ <para>
+ Recording altimeter for model rocketry.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Supports dual deployment (can fire 2 ejection charges).
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Barometric pressure sensor good to 100k feet MSL.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ On-board 1 megabyte non-volatile memory for flight data storage.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ USB interface for configuration, and data recovery.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Support for Li-Po rechargeable batteries (using an
+ external charger), or any 3.7-15V external battery.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ Uses Li-Po to fire e-matches, can be modified to support
+ optional separate pyro battery if needed.
+ </para>
+ </listitem>
+ <listitem>
+ <para>
+ 1.5 x .8 inch board designed to fit inside 24mm air-frame coupler tube.
+ </para>
+ </listitem>
+ </itemizedlist>
+ </section>
+ </chapter>
+ <chapter>
+ <title>FAQ</title>
+ <para>
+ TeleMetrum seems to shut off when disconnected from the
+ computer. Make sure the battery is adequately charged. Remember the
+ unit will pull more power than the USB port can deliver before the
+ GPS enters “locked” mode. The battery charges best when TeleMetrum
+ is turned off.
+ </para>
+ <para>
+ It's impossible to stop the TeleDongle when it's in “p” mode, I have
+ to unplug the USB cable? Make sure you have tried to “escape out” of
+ this mode. If this doesn't work the reboot procedure for the
+ TeleDongle *is* to simply unplug it. 'cu' however will retain it's
+ outgoing buffer IF your “escape out” ('~~') does not work.
+ At this point using either 'ao-view' (or possibly
+ 'cutemon') instead of 'cu' will 'clear' the issue and allow renewed
+ communication.
+ </para>
+ <para>
+ The amber LED (on the TeleMetrum) lights up when both
+ battery and USB are connected. Does this mean it's charging?
+ Yes, the yellow LED indicates the charging at the 'regular' rate.
+ If the led is out but the unit is still plugged into a USB port,
+ then the battery is being charged at a 'trickle' rate.
+ </para>
+ <para>
+ There are no “dit-dah-dah-dit” sound or lights like the manual mentions?
+ That's the “pad” mode. Weak batteries might be the problem.
+ It is also possible that the TeleMetrum is horizontal and the output
+ is instead a “dit-dit” meaning 'idle'. For TeleMini, it's possible that
+ it received a command packet which would have left it in “pad” mode.
+ </para>
+ <para>
+ How do I save flight data?
+ Live telemetry is written to file(s) whenever AltosUI is connected
+ to the TeleDongle. The file area defaults to ~/TeleMetrum
+ but is easily changed using the menus in AltosUI. The files that
+ are written end in '.telem'. The after-flight
+ data-dumped files will end in .eeprom and represent continuous data
+ unlike the .telem files that are subject to losses
+ along the RF data path.
+ See the above instructions on what and how to save the eeprom stored
+ data after physically retrieving your altimeter. Make sure to save
+ the on-board data after each flight; while the TeleMetrum can store
+ multiple flights, you never know when you'll lose the altimeter...
+ </para>
+ </chapter>
+ <appendix>
+ <title>Notes for Older Software</title>
+ <para>
+ <emphasis>
+ Before AltosUI was written, using Altus Metrum devices required
+ some finesse with the Linux command line. There was a limited
+ GUI tool, ao-view, which provided functionality similar to the
+ Monitor Flight window in AltosUI, but everything else was a
+ fairly 80's experience. This appendix includes documentation for
+ using that software.
+ </emphasis>
+ </para>
+ <para>
+ Both TeleMetrum and TeleDongle can be directly communicated
+ with using USB ports. The first thing you should try after getting
+ both units plugged into to your computer's USB port(s) is to run
+ 'ao-list' from a terminal-window to see what port-device-name each
+ device has been assigned by the operating system.
+ You will need this information to access the devices via their
+ respective on-board firmware and data using other command line
+ programs in the AltOS software suite.
+ </para>
+ <para>
+ TeleMini can be communicated with through a TeleDongle device
+ over the radio link. When first booted, TeleMini listens for a
+ TeleDongle device and if it receives a packet, it goes into
+ 'idle' mode. Otherwise, it goes into 'pad' mode and waits to be
+ launched. The easiest way to get it talking is to start the
+ communication link on the TeleDongle and the power up the
+ TeleMini board.
+ </para>
+ <para>
+ To access the device's firmware for configuration you need a terminal
+ program such as you would use to talk to a modem. The software
+ authors prefer using the program 'cu' which comes from the UUCP package
+ on most Unix-like systems such as Linux. An example command line for
+ cu might be 'cu -l /dev/ttyACM0', substituting the correct number
+ indicated from running the
+ ao-list program. Another reasonable terminal program for Linux is
+ 'cutecom'. The default 'escape'
+ character used by CU (i.e. the character you use to
+ issue commands to cu itself instead of sending the command as input
+ to the connected device) is a '~'. You will need this for use in
+ only two different ways during normal operations. First is to exit
+ the program by sending a '~.' which is called a 'escape-disconnect'
+ and allows you to close-out from 'cu'. The
+ second use will be outlined later.
+ </para>
+ <para>
+ All of the Altus Metrum devices share the concept of a two level
+ command set in their firmware.
+ The first layer has several single letter commands. Once
+ you are using 'cu' (or 'cutecom') sending (typing) a '?'
+ returns a full list of these
+ commands. The second level are configuration sub-commands accessed
+ using the 'c' command, for
+ instance typing 'c?' will give you this second level of commands
+ (all of which require the
+ letter 'c' to access). Please note that most configuration options
+ are stored only in Flash memory; TeleDongle doesn't provide any storage
+ for these options and so they'll all be lost when you unplug it.
+ </para>
+ <para>
+ Try setting these configuration ('c' or second level menu) values. A good
+ place to start is by setting your call sign. By default, the boards
+ use 'N0CALL' which is cute, but not exactly legal!
+ Spend a few minutes getting comfortable with the units, their
+ firmware, and 'cu' (or possibly 'cutecom').
+ For instance, try to send
+ (type) a 'c r 2' and verify the channel change by sending a 'c s'.
+ Verify you can connect and disconnect from the units while in your
+ terminal program by sending the escape-disconnect mentioned above.
+ </para>
+ <para>
+ To set the radio frequency, use the 'c R' command to specify the
+ radio transceiver configuration parameter. This parameter is computed
+ using the desired frequency, 'F', the radio calibration parameter, 'C' (showed by the 'c s' command) and
+ the standard calibration reference frequency, 'S', (normally 434.550MHz):
+ <programlisting>
+ R = F / S * C
+ </programlisting>
+ Round the result to the nearest integer value.
+ As with all 'c' sub-commands, follow this with a 'c w' to write the
+ change to the parameter block in the on-board flash on
+ your altimeter board if you want the change to stay in place across reboots.
+ </para>
+ <para>
+ To set the apogee delay, use the 'c d' command.
+ As with all 'c' sub-commands, follow this with a 'c w' to write the
+ change to the parameter block in the on-board DataFlash chip.
+ </para>
+ <para>
+ To set the main deployment altitude, use the 'c m' command.
+ As with all 'c' sub-commands, follow this with a 'c w' to write the
+ change to the parameter block in the on-board DataFlash chip.
+ </para>
+ <para>
+ To calibrate the radio frequency, connect the UHF antenna port to a
+ frequency counter, set the board to 434.550MHz, and use the 'C'
+ command to generate a CW carrier. Wait for the transmitter temperature
+ to stabilize and the frequency to settle down.
+ Then, divide 434.550 MHz by the
+ measured frequency and multiply by the current radio cal value show
+ in the 'c s' command. For an unprogrammed board, the default value
+ is 1186611. Take the resulting integer and program it using the 'c f'
+ command. Testing with the 'C' command again should show a carrier
+ within a few tens of Hertz of the intended frequency.
+ As with all 'c' sub-commands, follow this with a 'c w' to write the
+ change to the parameter block in the on-board DataFlash chip.
+ </para>
+ <para>
+ Note that the 'reboot' command, which is very useful on the altimeters,
+ will likely just cause problems with the dongle. The *correct* way
+ to reset the dongle is just to unplug and re-plug it.
+ </para>
+ <para>
+ A fun thing to do at the launch site and something you can do while
+ learning how to use these units is to play with the radio link access
+ between an altimeter and the TeleDongle. Be aware that you *must* create
+ some physical separation between the devices, otherwise the link will
+ not function due to signal overload in the receivers in each device.
+ </para>
+ <para>
+ Now might be a good time to take a break and read the rest of this
+ manual, particularly about the two “modes” that the altimeters
+ can be placed in. TeleMetrum uses the position of the device when booting
+ up will determine whether the unit is in “pad” or “idle” mode. TeleMini
+ enters “idle” mode when it receives a command packet within the first 5 seconds
+ of being powered up, otherwise it enters “pad” mode.
+ </para>
+ <para>
+ You can access an altimeter in idle mode from the TeleDongle's USB
+ connection using the radio link
+ by issuing a 'p' command to the TeleDongle. Practice connecting and
+ disconnecting ('~~' while using 'cu') from the altimeter. If
+ you cannot escape out of the “p” command, (by using a '~~' when in
+ CU) then it is likely that your kernel has issues. Try a newer version.
+ </para>
+ <para>
+ Using this radio link allows you to configure the altimeter, test
+ fire e-matches and igniters from the flight line, check pyro-match
+ continuity and so forth. You can leave the unit turned on while it
+ is in 'idle mode' and then place the
+ rocket vertically on the launch pad, walk away and then issue a
+ reboot command. The altimeter will reboot and start sending data
+ having changed to the “pad” mode. If the TeleDongle is not receiving
+ this data, you can disconnect 'cu' from the TeleDongle using the
+ procedures mentioned above and THEN connect to the TeleDongle from
+ inside 'ao-view'. If this doesn't work, disconnect from the
+ TeleDongle, unplug it, and try again after plugging it back in.
+ </para>
+ <para>
+ In order to reduce the chance of accidental firing of pyrotechnic
+ charges, the command to fire a charge is intentionally somewhat
+ difficult to type, and the built-in help is slightly cryptic to
+ prevent accidental echoing of characters from the help text back at
+ the board from firing a charge. The command to fire the apogee
+ drogue charge is 'i DoIt drogue' and the command to fire the main
+ charge is 'i DoIt main'.
+ </para>
+ <para>
+ On TeleMetrum, the GPS will eventually find enough satellites, lock in on them,
+ and 'ao-view' will both auditorily announce and visually indicate
+ that GPS is ready.
+ Now you can launch knowing that you have a good data path and
+ good satellite lock for flight data and recovery. Remember
+ you MUST tell ao-view to connect to the TeleDongle explicitly in
+ order for ao-view to be able to receive data.
+ </para>
+ <para>
+ The altimeters provide RDF (radio direction finding) tones on
+ the pad, during descent and after landing. These can be used to
+ locate the rocket using a directional antenna; the signal
+ strength providing an indication of the direction from receiver to rocket.
+ </para>
+ <para>
+ TeleMetrum also provides GPS tracking data, which can further simplify
+ locating the rocket once it has landed. (The last good GPS data
+ received before touch-down will be on the data screen of 'ao-view'.)
+ </para>
+ <para>
+ Once you have recovered the rocket you can download the eeprom
+ contents using either 'ao-dumplog' (or possibly 'ao-eeprom'), over
+ either a USB cable or over the radio link using TeleDongle.
+ And by following the man page for 'ao-postflight' you can create
+ various data output reports, graphs, and even KML data to see the
+ flight trajectory in Google-earth. (Moving the viewing angle making
+ sure to connect the yellow lines while in Google-earth is the proper
+ technique.)
+ </para>
+ <para>
+ As for ao-view.... some things are in the menu but don't do anything
+ very useful. The developers have stopped working on ao-view to focus
+ on a new, cross-platform ground station program. So ao-view may or
+ may not be updated in the future. Mostly you just use
+ the Log and Device menus. It has a wonderful display of the incoming
+ flight data and I am sure you will enjoy what it has to say to you
+ once you enable the voice output!
+ </para>
+ </appendix>
+ <appendix>
+ <title>Drill Templates</title>
+ <para>
+ These images, when printed, provide precise templates for the
+ mounting holes in Altus Metrum flight computers
+ </para>
+ <section>
+ <title>TeleMega template</title>
+ <para>
+ TeleMega has overall dimensions of 1.250 x 3.250 inches, and
+ the mounting holes are sized for use with 4-40 or M3 screws.
+ </para>
+ <mediaobject id="TeleMegaTemplate">
+ <imageobject>
+ <imagedata format="SVG" fileref="telemega-outline.svg"/>
+ </imageobject>
+ </mediaobject>
+ </section>
+ <section>
+ <title>TeleMetrum template</title>
+ <para>
+ TeleMetrum has overall dimensions of 1.000 x 2.750 inches, and the
+ mounting holes are sized for use with 4-40 or M3 screws.
+ </para>
+ <mediaobject id="TeleMetrumTemplate">
+ <imageobject>
+ <imagedata format="SVG" fileref="telemetrum.svg"/>
+ </imageobject>
+ </mediaobject>
+ </section>
+ <section>
+ <title>TeleMini v2/EasyMini template</title>
+ <para>
+ TeleMini v2 and EasyMini have overall dimensions of 0.800 x 1.500 inches, and the
+ mounting holes are sized for use with 4-40 or M3 screws.
+ </para>
+ <mediaobject id="MiniTemplate">
+ <imageobject>
+ <imagedata format="SVG" fileref="easymini-outline.svg"/>
+ </imageobject>
+ </mediaobject>
+ </section>
+ <section>
+ <title>TeleMini v1 template</title>
+ <para>
+ TeleMini has overall dimensions of 0.500 x 1.500 inches, and the
+ mounting holes are sized for use with 2-56 or M2 screws.
+ </para>
+ <mediaobject id="TeleMiniTemplate">
+ <imageobject>
+ <imagedata format="SVG" fileref="telemini.svg"/>
+ </imageobject>
+ </mediaobject>
+ </section>
+ </appendix>
+ <appendix>
+ <title>Calibration</title>
+ <para>
+ There are only two calibrations required for TeleMetrum and
+ TeleMega, and only one for TeleDongle, TeleMini and EasyMini.
+ All boards are shipped from the factory pre-calibrated, but
+ the procedures are documented here in case they are ever
+ needed. Re-calibration is not supported by AltosUI, you must
+ connect to the board with a serial terminal program and
+ interact directly with the on-board command interpreter to
+ effect calibration.
+ </para>
+ <section>
+ <title>Radio Frequency</title>
+ <para>
+ The radio frequency is synthesized from a clock based on the
+ crystal on the board. The actual frequency of this oscillator
+ must be measured to generate a calibration constant. While our
+ GFSK modulation
+ bandwidth is wide enough to allow boards to communicate even when
+ their oscillators are not on exactly the same frequency, performance
+ is best when they are closely matched.
+ Radio frequency calibration requires a calibrated frequency counter.
+ Fortunately, once set, the variation in frequency due to aging and
+ temperature changes is small enough that re-calibration by customers
+ should generally not be required.
+ </para>
+ <para>
+ To calibrate the radio frequency, connect the UHF antenna
+ port to a frequency counter, set the board to 434.550MHz,
+ and use the 'C' command in the on-board command interpreter
+ to generate a CW carrier. For USB-enabled boards, this is
+ best done over USB. For TeleMini v1, note that the only way
+ to escape the 'C' command is via power cycle since the board
+ will no longer be listening for commands once it starts
+ generating a CW carrier.
+ </para>
+ <para>
+ Wait for the transmitter temperature to stabilize and the frequency
+ to settle down. Then, divide 434.550 MHz by the
+ measured frequency and multiply by the current radio cal value show
+ in the 'c s' command. For an unprogrammed board, the default value
+ is 1186611. Take the resulting integer and program it using the 'c f'
+ command. Testing with the 'C' command again should show a carrier
+ within a few tens of Hertz of the intended frequency.
+ As with all 'c' sub-commands, follow this with a 'c w' to write the
+ change to the parameter block in the on-board storage chip.
+ </para>
+ <para>
+ Note that any time you re-do the radio frequency calibration, the
+ radio frequency is reset to the default 434.550 Mhz. If you want
+ to use another frequency, you will have to set that again after
+ calibration is completed.
+ </para>
+ </section>
+ <section>
+ <title>TeleMetrum and TeleMega Accelerometers</title>
+ <para>
+ While barometric sensors are factory-calibrated,
+ accelerometers are not, and so each must be calibrated once
+ installed in a flight computer. Explicitly calibrating the
+ accelerometers also allows us to load any compatible device.
+ We perform a two-point calibration using gravity.
+ </para>
+ <para>
+ To calibrate the acceleration sensor, use the 'c a 0' command. You
+ will be prompted to orient the board vertically with the UHF antenna
+ up and press a key, then to orient the board vertically with the
+ UHF antenna down and press a key. Note that the accuracy of this
+ calibration depends primarily on how perfectly vertical and still
+ the board is held during the cal process. As with all 'c'
+ sub-commands, follow this with a 'c w' to write the
+ change to the parameter block in the on-board DataFlash chip.
+ </para>
+ <para>
+ The +1g and -1g calibration points are included in each telemetry
+ frame and are part of the header stored in onboard flash to be
+ downloaded after flight. We always store and return raw ADC
+ samples for each sensor... so nothing is permanently “lost” or
+ “damaged” if the calibration is poor.
+ </para>
+ <para>
+ In the unlikely event an accel cal goes badly, it is possible
+ that TeleMetrum or TeleMega may always come up in 'pad mode'
+ and as such not be listening to either the USB or radio link.
+ If that happens, there is a special hook in the firmware to
+ force the board back in to 'idle mode' so you can re-do the
+ cal. To use this hook, you just need to ground the SPI clock
+ pin at power-on. This pin is available as pin 2 on the 8-pin
+ companion connector, and pin 1 is ground. So either
+ carefully install a fine-gauge wire jumper between the two
+ pins closest to the index hole end of the 8-pin connector, or
+ plug in the programming cable to the 8-pin connector and use
+ a small screwdriver or similar to short the two pins closest
+ to the index post on the 4-pin end of the programming cable,
+ and power up the board. It should come up in 'idle mode'
+ (two beeps), allowing a re-cal.
+ </para>
+ </section>
+ </appendix>
+ <appendix>
+ <title>Release Notes</title>
+ <simplesect>
+ <title>Version 1.3</title>
+ <xi:include
+ xmlns:xi="http://www.w3.org/2001/XInclude"
+ href="release-notes-1.3.xsl"
+ xpointer="xpointer(/article/*)"/>
+ </simplesect>
+ <simplesect>
+ <title>Version 1.2.1</title>
+ <xi:include
+ xmlns:xi="http://www.w3.org/2001/XInclude"
+ href="release-notes-1.2.1.xsl"
+ xpointer="xpointer(/article/*)"/>
+ </simplesect>
+ <simplesect>
+ <title>Version 1.2</title>
+ <xi:include
+ xmlns:xi="http://www.w3.org/2001/XInclude"
+ href="release-notes-1.2.xsl"
+ xpointer="xpointer(/article/*)"/>
+ </simplesect>
+ <simplesect>
+ <title>Version 1.1.1</title>
+ <xi:include
+ xmlns:xi="http://www.w3.org/2001/XInclude"
+ href="release-notes-1.1.1.xsl"
+ xpointer="xpointer(/article/*)"/>
+ </simplesect>
+ <simplesect>
+ <title>Version 1.1</title>
+ <xi:include
+ xmlns:xi="http://www.w3.org/2001/XInclude"
+ href="release-notes-1.1.xsl"
+ xpointer="xpointer(/article/*)"/>
+ </simplesect>
+ <simplesect>
+ <title>Version 1.0.1</title>
+ <xi:include
+ xmlns:xi="http://www.w3.org/2001/XInclude"
+ href="release-notes-1.0.1.xsl"
+ xpointer="xpointer(/article/*)"/>
+ </simplesect>
+ <simplesect>
+ <title>Version 0.9.2</title>
+ <xi:include
+ xmlns:xi="http://www.w3.org/2001/XInclude"
+ href="release-notes-0.9.2.xsl"
+ xpointer="xpointer(/article/*)"/>
+ </simplesect>
+ <simplesect>
+ <title>Version 0.9</title>
+ <xi:include
+ xmlns:xi="http://www.w3.org/2001/XInclude"
+ href="release-notes-0.9.xsl"
+ xpointer="xpointer(/article/*)"/>
+ </simplesect>
+ <simplesect>
+ <title>Version 0.8</title>
+ <xi:include
+ xmlns:xi="http://www.w3.org/2001/XInclude"
+ href="release-notes-0.8.xsl"
+ xpointer="xpointer(/article/*)"/>
+ </simplesect>
+ <simplesect>
+ <title>Version 0.7.1</title>
+ <xi:include
+ xmlns:xi="http://www.w3.org/2001/XInclude"
+ href="release-notes-0.7.1.xsl"
+ xpointer="xpointer(/article/*)"/>
+ </simplesect>
+ </appendix>
+</book>
+
+<!-- LocalWords: Altusmetrum
+-->
\ No newline at end of file
projects / fw / altos / blobdiff