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diff --git a/doc/altusmetrum.xsl b/doc/altusmetrum.xsl new file mode 100644 index 00000000..8339ca43 --- /dev/null +++ b/doc/altusmetrum.xsl @@ -0,0 +1,2495 @@ +<?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, TeleMini and TeleDongle Devices</subtitle> + <bookinfo> + <author> + <firstname>Bdale</firstname> + <surname>Garbee</surname> + </author> + <author> + <firstname>Keith</firstname> + <surname>Packard</surname> + </author> + <author> + <firstname>Bob</firstname> + <surname>Finch</surname> + </author> + <author> + <firstname>Anthony</firstname> + <surname>Towns</surname> + </author> + <copyright> + <year>2011</year> + <holder>Bdale Garbee and Keith Packard</holder> + </copyright> + <legalnotice> + <para> + This document is released under the terms of the + <ulink url="http://creativecommons.org/licenses/by-sa/3.0/"> + Creative Commons ShareAlike 3.0 + </ulink> + license. + </para> + </legalnotice> + <revhistory> + <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> + <revremark>Updated for software version 0.8 </revremark> + </revision> + </revhistory> + </bookinfo> + <acknowledgements> + <para> + 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 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 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! + </para> + <para> + Have fun using these products, and we hope to meet all of you + out on the rocket flight line somewhere. + <literallayout> +Bdale Garbee, KB0G +NAR #87103, TRA #12201 + +Keith Packard, KD7SQG +NAR #88757, TRA #12200 + </literallayout> + </para> + </acknowledgements> + <chapter> + <title>Introduction and Overview</title> + <para> + Welcome to the Altus Metrum community! Our circuits and software reflect + our passion for both hobby rocketry and Free Software. We hope their + capabilities and performance will delight you in every way, but by + releasing all of our hardware and software designs under open licenses, + we also hope to empower you to take as active a role in our collective + future as you wish! + </para> + <para> + 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. + </para> + <para> + The newest device is TeleMini, a dual deploy altimeter with + radio telemetry and radio direction finding. This device is only + 13mm by 38mm (½ inch by 1½ inches) and can fit easily in an 18mm + air-frame. + </para> + <para> + Complementing TeleMetrum and TeleMini is TeleDongle, a USB to RF + interface 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> + 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. + </para> + <para> + The TeleMetrum battery can be charged 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. + </para> + <para> + 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> + The TeleMini battery can be charged by disconnecting it from the + TeleMini board and plugging it into a standalone battery charger + board, and connecting that via a USB cable to a laptop or other USB + power source + </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. 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> + Next you should obtain and install the AltOS software. These include + the AltosUI ground station program, current firmware images for + TeleMetrum, TeleMini and TeleDongle, 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> + </chapter> + <chapter> + <title>Handling Precautions</title> + <para> + 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 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 air-frame. We + often wrap them in suitable scraps of closed-cell packing foam before + strapping them down, for example. + </para> + <para> + The barometric sensors used on both TeleMetrum and TeleMini are + sensitive to sunlight. In normal TeleMetrum mounting situations, it + 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 an air-frame with a + see-through plastic payload bay. It is particularly important to + consider this with TeleMini, 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 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, and also by having a + suitable static vent to outside air. + </para> + <para> + 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>Hardware Overview</title> + <para> + TeleMetrum is a 1 inch by 2.75 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 1/4 + 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> + <para> + TeleMini is a 0.5 inch by 1.5 inch circuit board. 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 1/4 + wave UHF wire antenna attached to the center of one 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 + other end of the board, meaning an ideal "simple" avionics + bay for TeleMini should have at least 9 inches of interior length. + </para> + <para> + A typical TeleMetrum or TeleMini installation 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. All Altus Metrum products are + designed for use with single-cell batteries with 3.7 volts nominal. + </para> + <para> + By default, we use the unregulated output of the Li-Po 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> + 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> + TeleMetrum also uses the screw terminal block for the power + switch leads. On TeleMini, 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, you can unplug the integrated GPS + antenna and select an appropriate off-board GPS antenna with + cable terminating in a U.FL connector. + </para> + </chapter> + <chapter> + <title>System Operation</title> + <section> + <title>Firmware Modes </title> + <para> + 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 doesn't have an accelerometer we can + use to determine orientation, "idle" mode is selected when the + board receives a command packet within the first five seconds + of operation; if no packet is received, the board enters + "flight" mode. + </para> + <para> + 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 to a TeleMetrum in idle mode + over either + USB or the radio link equivalently. TeleMini 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 is 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> + </section> + <section> + <title>GPS </title> + <para> + TeleMetrum includes 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 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. + </para> + <para> + TeleMetrum provides 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 TeleMetrum + 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> + <title>Controlling An Altimeter Over The Radio Link</title> + <para> + 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 radio + link. TeleMini 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 + 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, 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> + <para> + Save Flight Data—Recover flight data from the rocket without + opening it up. + </para> + </listitem> + <listitem> + <para> + Configure altimeter apogee delays or main deploy heights + to respond to changing launch conditions. You can also + 'reboot' the altimeter. Use this to remotely enable the + flight computer by turning TeleMetrum 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 air-frame. Simply assembly the + rocket as if for flight with the apogee and main charges + loaded, then remotely command the altimeter to fire the + igniters. + </para> + </listitem> + </itemizedlist> + <para> + 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> + TeleMetrum only enables radio commanding 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. + </para> + <para> + 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> + 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 tramsitted, while the green LED will light up on TeleDongle when + it is waiting to receive a packet from the altimeter. + </para> + </section> + <section> + <title>Ground Testing </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 radio link central to the Altus Metrum system, + this can be accomplished in a TeleMetrum or TeleMini equipped rocket + with less work than you may be accustomed to with other systems. It + can even be fun! + </para> + <para> + Just prep the rocket for flight, then power up the altimeter + in "idle" mode (placing air-frame horizontal for TeleMetrum or + selected 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 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> + 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 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 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 great 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 over time, and would of course appreciate customer feedback + on performance in higher altitude flights! + </para> + </section> + <section> + <title>Configurable Parameters</title> + <para> + Configuring an Altus Metrum altimeter for flight is very + simple. Even on our baro-only TeleMini board, 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> + TeleMetrum version 1.1 and 1.2 have 2MB of on-board flash storage, + enough to hold over 40 minutes of data at full data rate + (100 samples/second). TeleMetrum 1.0 has 1MB of on-board + storage. As data are stored at a reduced rate during descent + (10 samples/second), there's plenty of space to store many + flights worth of data. + </para> + <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 TeleMetrum can store more + flights. + </para> + <para> + All of the configuration data is also stored in the flash + memory, which consumes 64kB on TeleMetrum v1.1/v1.2 and 256B on + TeleMetrum v1.0. This configuration space is not available + for storing flight log data. + </para> + <para> + To compute the amount of space needed for a single flight, + you can multiply the expected ascent time (in seconds) by + 800, multiply the expected descent time (in seconds) by 80 + and add the two together. That will slightly under-estimate + the storage (in bytes) needed for the flight. For instance, + a flight spending 20 seconds in ascent and 150 seconds in + descent will take about (20 * 800) + (150 * 80) = 28000 + bytes of storage. You could store dozens of these flights in + the on-board flash. + </para> + <para> + The default size, 192kB, allows for 10 flights of storage on + TeleMetrum v1.1/v1.2 and 5 flights on TeleMetrum v1.0. This + ensures that you won't need to erase the memory before + flying each time while still allowing more than sufficient + storage for each flight. + </para> + <para> + As TeleMini does not contain an accelerometer, it stores + data at 10 samples per second during ascent and one sample + per second during descent. Each sample is a two byte reading + from the barometer. These are stored in 5kB of + on-chip flash memory which can hold 256 seconds at the + ascent rate or 2560 seconds at the descent rate. Because of + the limited storage, TeleMini cannot hold data for more than + one flight, and so must be erased after each flight or it + will not capture data for subsequent flights. + </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 + TeleMetrum computers, 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 measures 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, TeleMetrum must be + explicitly configured for either Antenna Up or Antenna + Down. The default, Antenna Up, expects the end of the + TeleMetrum 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> + + </chapter> + <chapter> + + <title>AltosUI</title> + <para> + The AltosUI program provides a graphical user interface for + interacting with the Altus Metrum product family, including + TeleMetrum, TeleMini and TeleDongle. AltosUI can monitor telemetry data, + configure TeleMetrum, TeleMini 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>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 configured call-sign</para> + </listitem> + <listitem> + <para>The device serial number</para> + </listitem> + <listitem> + <para>The flight number. Each altimeter remembers how many + times it has flown. + </para> + </listitem> + <listitem> + <para> + The rocket flight state. Each flight passes through several + states including Pad, Boost, Fast, Coast, Drogue, Main and + Landed. + </para> + </listitem> + <listitem> + <para> + 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 receivable. The packet link uses + error detection and correction techniques which prevent + incorrect data from being reported. + </para> + </listitem> + </itemizedlist> + <para> + Finally, the largest portion of the window contains a set of + tabs, each of which contain some information about the rocket. + 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 displays all of + the raw telemetry values in one place in a spreadsheet-like format. + </para> + <section> + <title>Launch Pad</title> + <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: + <itemizedlist> + <listitem> + <para> + Battery Voltage. 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 + 3.7V 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 Li-Po 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 Li-Po battery voltage. A value greater than 3.2V is + required for a 'GO' status. + </para> + </listitem> + <listitem> + <para> + On-board Data Logging. 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> + <listitem> + <para> + GPS Locked. For a TeleMetrum 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> + <listitem> + <para> + GPS Ready. For a TeleMetrum 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> + </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> + </para> + </section> + <section> + <title>Ascent</title> + <para> + This tab is shown during Boost, Fast and Coast + phases. The information displayed here helps monitor the + rocket as it heads towards apogee. + </para> + <para> + The height, speed and acceleration are shown along with the + 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 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 + start reporting position again. + </para> + <para> + Finally, the current igniter voltages are reported as in the + Launch Pad tab. This can help diagnose deployment failures + caused by wiring which comes loose under high acceleration. + </para> + </section> + <section> + <title>Descent</title> + <para> + Once the rocket has reached apogee and (we hope) activated the + apogee charge, attention switches to tracking the rocket on + the way back to the ground, and for dual-deploy flights, + waiting for the main charge to fire. + </para> + <para> + To monitor whether the apogee charge operated correctly, the + current descent rate is reported along with the current + 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> + 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. 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. 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 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> + <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 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> + 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 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 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 centered while data is being received. + </para> + <para> + Images are fetched automatically via the Google Maps Static API, + 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> + 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. 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 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 + flight data saved in the device will be shown allowing you to + 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 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 during the next flight. + </para> + <para> + The file name for each flight log is computed automatically + from the recorded flight date, altimeter serial number and + flight number information. + </para> + </section> + <section> + <title>Replay Flight</title> + <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 altimeter + flash memory. + </para> + <para> + Once a flight record is selected, the flight monitor interface + is displayed and the flight is re-enacted in real time. Check + the Monitor Flight chapter above to learn how this window operates. + </para> + </section> + <section> + <title>Graph Data</title> + <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 + flash memory. + </para> + <para> + Once a flight record is selected, a window with two tabs is + opened. The first tab contains a graph with acceleration + (blue), velocity (green) and altitude (red) of the flight, + measured in metric units. The + apogee(yellow) and main(magenta) igniter voltages are also + displayed; high voltages indicate continuity, low voltages + indicate open circuits. The second tab contains some basic + flight statistics. + </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 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. + 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 + 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 + where to write the resulting file. It has a selector to choose + between CSV and KML file formats. + </para> + <section> + <title>Comma Separated Value Format</title> + <para> + 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 altimeter, then + there is a single header line which labels all of the + fields. All of these lines start with a '#' character which + many tools can be configured to skip over. + </para> + <para> + The remaining lines of the file contain the data, with each + field separated by a comma and at least one space. All of + the sensor values are converted to standard units, with the + barometric data reported in both pressure, altitude and + height above pad units. + </para> + </section> + <section> + <title>Keyhole Markup Language (for Google Earth)</title> + <para> + 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 Altimeter</title> + <para> + Select this button and then select either a TeleMetrum or + TeleDongle Device from the list provided. Selecting a TeleDongle + 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 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 + 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 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> + <listitem> + <para> + Close. This closes the dialog. Any unsaved changes will be + lost. + </para> + </listitem> + </itemizedlist> + <para> + The rest of the dialog contains the parameters to be configured. + </para> + <section> + <title>Main Deploy Altitude</title> + <para> + This sets the altitude (above the recorded pad altitude) at + which the 'main' igniter will fire. The drop-down menu shows + some common values, but you can edit the text directly and + choose whatever you like. If the apogee charge fires below + this altitude, then the main charge will fire two seconds + after the apogee charge fires. + </para> + </section> + <section> + <title>Apogee Delay</title> + <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 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 Frequency</title> + <para> + This configures which of the configured 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 frequency before you will be able to use packet + command mode again. + </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. 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>Callsign</title> + <para> + This sets the call sign included in each telemetry packet. Set this + as needed to conform to your local radio regulations. + </para> + </section> + <section> + <title>Maximum Flight Log Size</title> + <para> + This sets the space (in kilobytes) allocated for each flight + log. The available space will be divided into chunks of this + 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> + 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> + <itemizedlist> + <listitem> + <para> + Dual Deploy. 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> + <listitem> + <para> + Redundant Apogee. This fires both channels at + apogee, the 'apogee' channel first followed after a two second + delay by the 'main' channel. + </para> + </listitem> + <listitem> + <para> + Redundant Main. 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> + </itemizedlist> + </section> + <section> + <title>Pad Orientation</title> + <para> + Because it includes an accelerometer, TeleMetrum is + 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> + <itemizedlist> + <listitem> + <para> + Antenna Up. In this mode, the antenna end of the + TeleMetrum board must point forward, in line with the + expected flight path. + </para> + </listitem> + <listitem> + <para> + Antenna Down. In this mode, the antenna end of the + TeleMetrum board must point aft, in line with the + expected flight path. + </para> + </listitem> + </itemizedlist> + </section> + </section> + <section> + <title>Configure AltosUI</title> + <para> + This button presents a dialog so that you can configure the AltosUI global settings. + </para> + <section> + <title>Voice Settings</title> + <para> + 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. + </para> + <itemizedlist> + <listitem> + <para>Enable—turns all voice announcements on and off</para> + </listitem> + <listitem> + <para> + Test Voice—Plays a short message allowing you to verify + that the audio system is working and the volume settings + are reasonable + </para> + </listitem> + </itemizedlist> + </section> + <section> + <title>Log Directory</title> + <para> + AltosUI logs all telemetry data and saves all TeleMetrum flash + data to this directory. This directory is also used as the + staring point when selecting data files for display or export. + </para> + <para> + Click on the directory name to bring up a directory choosing + dialog, select a new directory and click 'Select Directory' to + change where AltosUI reads and writes data files. + </para> + </section> + <section> + <title>Callsign</title> + <para> + 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> + </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> + <para> + This causes all communication with a connected device to be + dumped to the console from which AltosUI was started. If + you've started it from an icon or menu entry, the output + will simply be discarded. This mode can be useful to debug + 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>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 flashing devices in the Updating Device + Firmware chapter below. + </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. + </para> + <para> + Next, select the image to flash to the device. These are named + with the product name and firmware version. The file selector + will start in the directory containing the firmware included + with the AltosUI package. Navigate to the directory containing + the desired firmware if it isn't there. + </para> + <para> + Next, a small dialog containing the device serial number and + RF calibration values should appear. If these values are + incorrect (possibly due to a corrupted image in the device), + enter the correct values here. + </para> + <para> + Finally, a dialog containing a progress bar will follow the + programming process. + </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. + </para> + </section> + <section> + <title>Fire Igniter</title> + <para> + This activates the igniter circuits in TeleMetrum to help test + 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 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 + continuity test status for both apogee and main charges. + </para> + <para> + Next, select the desired igniter to fire. This will enable the + 'Arm' button. + </para> + <para> + Select the 'Arm' button. This enables the 'Fire' button. The + word 'Arm' is replaced by a countdown timer indicating that + you have 10 seconds to press the 'Fire' button or the system + will deactivate, at which point you start over again at + 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. + </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 + feed-line connected to one of our <ulink url="http://www.altusmetrum.org/TeleDongle/">TeleDongle</ulink> units. 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. + </para> + <para> + The GUI tool, AltosUI, is written in Java and runs across + Linux, Mac OS and Windows. There's also a suite of C tools + for Linux which can perform most of the same tasks. + </para> + <para> + 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 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 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-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 + 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. + </para> + <para> + So, to recap, on the ground the hardware you'll need includes: + <orderedlist inheritnum='inherit' numeration='arabic'> + <listitem> + an antenna and feed-line + </listitem> + <listitem> + a TeleDongle + </listitem> + <listitem> + a notebook computer + </listitem> + <listitem> + optionally, a hand-held GPS receiver + </listitem> + <listitem> + optionally, an HT or receiver covering 435 MHz + </listitem> + </orderedlist> + </para> + <para> + The best hand-held commercial directional antennas we've found for radio + direction finding rockets are from + <ulink url="http://www.arrowantennas.com/" > + Arrow Antennas. + </ulink> + The 440-3 and 440-5 are both good choices for finding a + TeleMetrum- or TeleMini- equipped rocket when used with a suitable 70cm HT. + </para> + </section> + <section> + <title>Data Analysis</title> + <para> + Our software makes it easy to log the data from each flight, both the + 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 TeleMetrum data file + usable with Google Maps and Google Earth for visualizing the flight path + in two or three dimensions! + </para> + <para> + Our ultimate goal is to emit a set of files for each flight that can be + published as a web page per flight, or just viewed on your local disk with + a web browser. + </para> + </section> + <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. + </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. + </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... + </para> + </section> + </chapter> + <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" 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> + Make sure TeleMetrum is aligned precisely along the axis of + acceleration so that the accelerometer can accurately + capture data during the flight. + </listitem> + <listitem> + 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. + </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> + 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. + </listitem> + <listitem> + 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. + </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> + Keep wires from different circuits apart. Moving circuits + further apart will reduce RFI. + </listitem> + <listitem> + 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. + </listitem> + <listitem> + 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. + </listitem> + <listitem> + 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 1/4 + of the wavelength (17.5cm). + </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> + The big concept to understand is that you have to use a + TeleDongle as a programmer to update a TeleMetrum or TeleMini, + and a TeleMetrum or other TeleDongle to program the TeleDongle + Due to limited memory resources in the cc1111, we don't support + programming 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 the altimeter 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-v1.2-1.0.0.ihx. It should be visible + in the default directory, if not you may have to poke around + your system to find it. + </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 TeleMini Firmware</title> + <orderedlist inheritnum='inherit' numeration='arabic'> + <listitem> + 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. + </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-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. + </listitem> + <listitem> + Attach a battery to the TeleMini board. + </listitem> + <listitem> + Plug the TeleDongle into your computer's USB port, and power + up the TeleMini + </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 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. + </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 TeleMini with new firmware, showing a progress bar. + </listitem> + <listitem> + 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. + </listitem> + <listitem> + If something goes wrong, give it another try. + </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> + 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 or TeleDongle. + </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 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. + </listitem> + <listitem> + Attach a battery to the TeleMetrum board if you're using one. + </listitem> + <listitem> + Plug both the programmer and the TeleDongle into your computer's USB + ports, and power up the programmer. + </listitem> + <listitem> + Run AltosUI, and select 'Flash Image' from the File menu. + </listitem> + <listitem> + Pick the programmer 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-v0.2-1.0.0.ihx. It should be visible + in the default directory, if not you may have to poke around + your system to find it. + </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> + <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>TeleMetrum 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 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 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 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 battery charging, 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> + </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>Calibration</title> + <para> + There are only two calibrations required for a TeleMetrum board, and + only one for TeleDongle and TeleMini. 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 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 434.550MHz, and use the 'C' + command in the on-board command interpreter to generate a CW + carrier. For TeleMetrum, this is best done over USB. For TeleMini, + 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 DataFlash 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 Accelerometer</title> + <para> + The TeleMetrum 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 ratio-metric to + the ADC converter, and calibration is required. Explicitly + calibrating the accelerometers also allows us to load any device + 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. 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 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 + xmlns:xi="http://www.w3.org/2001/XInclude"> + <title>Release Notes</title> + <xi:include href="release-notes-1.1.xsl" xpointer="xpointer(/article/*)"/> + <xi:include href="release-notes-1.0.1.xsl" xpointer="xpointer(/article/*)"/> + <xi:include href="release-notes-0.9.2.xsl" xpointer="xpointer(/article/*)"/> + <xi:include href="release-notes-0.9.xsl" xpointer="xpointer(/article/*)"/> + <xi:include href="release-notes-0.8.xsl" xpointer="xpointer(/article/*)"/> + <xi:include href="release-notes-0.7.1.xsl" xpointer="xpointer(/article/*)"/> + </appendix> +</book> + +<!-- LocalWords: Altusmetrum +--> |