1 <?xml version="1.0" encoding="utf-8" ?>
2 <!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook XML V4.5//EN"
3 "/usr/share/xml/docbook/schema/dtd/4.5/docbookx.dtd">
5 <title>The Altus Metrum System</title>
6 <subtitle>An Owner's Manual for TeleMetrum, TeleMini and TeleDongle Devices</subtitle>
9 <firstname>Bdale</firstname>
10 <surname>Garbee</surname>
13 <firstname>Keith</firstname>
14 <surname>Packard</surname>
17 <firstname>Bob</firstname>
18 <surname>Finch</surname>
21 <firstname>Anthony</firstname>
22 <surname>Towns</surname>
26 <holder>Bdale Garbee and Keith Packard</holder>
30 This document is released under the terms of the
31 <ulink url="http://creativecommons.org/licenses/by-sa/3.0/">
32 Creative Commons ShareAlike 3.0
39 <revnumber>1.0</revnumber>
40 <date>10 August 2011</date>
42 Updated for software version 1.0. Note that 1.0 represents a
43 telemetry format change, meaning both ends of a link (TeleMetrum/TeleMini and
44 TeleDongle) must be updated or communications will fail.
48 <revnumber>0.9</revnumber>
49 <date>18 January 2011</date>
51 Updated for software version 0.9. Note that 0.9 represents a
52 telemetry format change, meaning both ends of a link (TeleMetrum and
53 TeleDongle) must be updated or communications will fail.
57 <revnumber>0.8</revnumber>
58 <date>24 November 2010</date>
59 <revremark>Updated for software version 0.8 </revremark>
65 Thanks to Bob Finch, W9YA, NAR 12965, TRA 12350 for writing "The
66 Mere-Mortals Quick Start/Usage Guide to the Altus Metrum Starter
67 Kit" which has turned into the Getting Started chapter in this
68 book. Bob was one of our first customers for a production
69 TeleMetrum, and the enthusiasm that led to his contribution of
70 this section is immensely gratifying and highy appreciated!
73 And thanks to Anthony (AJ) Towns for contributing the
74 AltosUI graphing and site map code and documentation. Free
75 software means that our customers and friends can become our
76 collaborators, and we certainly appreciate this level of
80 Have fun using these products, and we hope to meet all of you
81 out on the rocket flight line somewhere.
84 NAR #87103, TRA #12201
87 NAR #88757, TRA #12200
92 <title>Introduction and Overview</title>
94 Welcome to the Altus Metrum community! Our circuits and software reflect
95 our passion for both hobby rocketry and Free Software. We hope their
96 capabilities and performance will delight you in every way, but by
97 releasing all of our hardware and software designs under open licenses,
98 we also hope to empower you to take as active a role in our collective
102 The first device created for our community is TeleMetrum, a dual
103 deploy altimeter with fully integrated GPS and radio telemetry
104 as standard features, and a "companion interface" that will
105 support optional capabilities in the future.
108 The newest device is TeleMini, a dual deploy altimeter with
109 radio telemetry and radio direction finding. This device is only
110 13mm by 38mm (½ inch by 1½ inches) and can fit easily in an 18mm airframe.
113 Complementing TeleMetrum and TeleMini is TeleDongle, a USB to RF interface for
114 communicating with the altimeters. Combined with your choice of antenna and
115 notebook computer, TeleDongle and our associated user interface software
116 form a complete ground station capable of logging and displaying in-flight
117 telemetry, aiding rocket recovery, then processing and archiving flight
118 data for analysis and review.
121 More products will be added to the Altus Metrum family over time, and
122 we currently envision that this will be a single, comprehensive manual
123 for the entire product family.
127 <title>Getting Started</title>
129 The first thing to do after you check the inventory of parts in your
130 "starter kit" is to charge the battery.
133 The TeleMetrum battery can be charged by plugging it into the
134 corresponding socket of the TeleMetrum and then using the USB A to
136 cable to plug the Telemetrum into your computer's USB socket. The
137 TeleMetrum circuitry will charge the battery whenever it is plugged
138 in, because the TeleMetrum's on-off switch does NOT control the
142 When the GPS chip is initially searching for
143 satellites, TeleMetrum will consume more current than it can pull
144 from the usb port, so the battery must be attached in order to get
145 satellite lock. Once GPS is locked, the current consumption goes back
146 down enough to enable charging while
147 running. So it's a good idea to fully charge the battery as your
148 first item of business so there is no issue getting and maintaining
149 satellite lock. The yellow charge indicator led will go out when the
150 battery is nearly full and the charger goes to trickle charge. It
151 can take several hours to fully recharge a deeply discharged battery.
154 The TeleMini battery can be charged by disconnecting it from the
155 TeleMini board and plugging it into the battery charger board,
156 and connecting that via a USB cable to a laptop or other USB
160 The other active device in the starter kit is the TeleDongle USB to
161 RF interface. If you plug it in to your Mac or Linux computer it should
162 "just work", showing up as a serial port device. Windows systems need
163 driver information that is part of the AltOS download to know that the
164 existing USB modem driver will work. If you are using Linux and are
165 having problems, try moving to a fresher kernel (2.6.33 or newer), as
166 the USB serial driver had ugly bugs in some earlier versions.
169 Next you should obtain and install the AltOS utilities. These include
170 the AltosUI ground station program, current firmware images for
171 TeleMetrum, TeleMini and TeleDongle, and a number of standalone utilities that
172 are rarely needed. Pre-built binary packages are available for Debian
173 Linux, Microsoft Windows, and recent MacOSX versions. Full sourcecode
174 and build instructions for some other Linux variants are also available.
175 The latest version may always be downloaded from
176 <ulink url="http://altusmetrum.org/AltOS"/>.
180 <title>Handling Precautions</title>
182 All Altus Metrum products are sophisticated electronic device. When handled gently and
183 properly installed in an airframe, theywill deliver impressive results.
184 However, like all electronic devices, there are some precautions you
188 The Lithium Polymer rechargeable batteries have an
189 extraordinary power density. This is great because we can fly with
190 much less battery mass than if we used alkaline batteries or previous
191 generation rechargeable batteries... but if they are punctured
192 or their leads are allowed to short, they can and will release their
194 Thus we recommend that you take some care when handling our batteries
195 and consider giving them some extra protection in your airframe. We
196 often wrap them in suitable scraps of closed-cell packing foam before
197 strapping them down, for example.
200 The barometric sensor is sensitive to sunlight. In normal
201 mounting situations, it and all of the other surface mount components
202 are "down" towards whatever the underlying mounting surface is, so
203 this is not normally a problem. Please consider this, though, when
204 designing an installation, for example, in an airframe with a
205 see-through plastic payload bay.
208 The barometric sensor sampling port must be able to
210 both by not being covered by foam or tape or other materials that might
211 directly block the hole on the top of the sensor, but also by having a
212 suitable static vent to outside air.
215 As with all other rocketry electronics, Altus Metrum altimeters must be protected
216 from exposure to corrosive motor exhaust and ejection charge gasses.
220 <title>Hardware Overview</title>
222 TeleMetrum is a 1 inch by 2.75 inch circuit board. It was designed to
223 fit inside coupler for 29mm airframe tubing, but using it in a tube that
224 small in diameter may require some creativity in mounting and wiring
225 to succeed! The default 1/4
226 wave UHF wire antenna attached to the center of the nose-cone end of
227 the board is about 7 inches long, and wiring for a power switch and
228 the e-matches for apogee and main ejection charges depart from the
229 fin can end of the board. Given all this, an ideal "simple" avionics
230 bay for TeleMetrum should have at least 10 inches of interior length.
233 TeleMini is a 0.5 inch by 1.5 inch circuit board. It was designed to
234 fit inside an 18mm airframe tube, but using it in a tube that
235 small in diameter may require some creativity in mounting and wiring
236 to succeed! The default 1/4
237 wave UHF wire antenna attached to the center of the nose-cone end of
238 the board is about 7 inches long, and wiring for a power switch and
239 the e-matches for apogee and main ejection charges depart from the
240 fin can end of the board. Given all this, an ideal "simple" avionics
241 bay for TeleMini should have at least 9 inches of interior length.
244 A typical TeleMetrum or TeleMini installation using the on-board devices and
245 default wire UHF antenna involves attaching only a suitable
246 Lithium Polymer battery, a single pole switch for power on/off, and
247 two pairs of wires connecting e-matches for the apogee and main ejection
251 By default, we use the unregulated output of the LiPo battery directly
252 to fire ejection charges. This works marvelously with standard
253 low-current e-matches like the J-Tek from MJG Technologies, and with
254 Quest Q2G2 igniters. However, if you
255 want or need to use a separate pyro battery, check out the "External Pyro Battery"
256 section in this manual for instructions on how to wire that up. The
257 altimeters are designed to work with an external pyro battery of up to 15V.
260 Ejection charges are wired directly to the screw terminal block
261 at the aft end of the altimeter. This is very similar to what
262 most other altimeter vendors provide and so may be the most
263 familiar option. You'll need a very small straight blade
264 screwdriver to connect and disconnect the board in this case,
265 such as you might find in a jeweler's screwdriver set.
268 TeleMetrum also uses the screw terminal block for the power
269 switch leads. On TeleMini, the power switch leads are soldered
270 directly to the board and can be connected directly to the switch.
273 For most airframes, the integrated antennas are more than
274 adequate However, if you are installing in a carbon-fiber
275 electronics bay which is opaque to RF signals, you may need to
276 use off-board external antennas instead. In this case, you can
277 order an altimeter with an SMA connector for the UHF antenna
278 connection, and, on TeleMetrum, you can unplug the integrated GPS
279 antenna and select an appropriate off-board GPS antenna with
280 cable terminating in a U.FL connector.
284 <title>System Operation</title>
286 <title>Firmware Modes </title>
288 The AltOS firmware build for the altimeters has two
289 fundamental modes, "idle" and "flight". Which of these modes
290 the firmware operates in is determined at startup time. For
291 TeleMetrum, the mode is controlled by the orientation of the
292 rocket (well, actually the board, of course...) at the time
293 power is switched on. If the rocket is "nose up", then
294 TeleMetrum assumes it's on a rail or rod being prepared for
295 launch, so the firmware chooses flight mode. However, if the
296 rocket is more or less horizontal, the firmware instead enters
297 idle mode. For TeleMini, "idle" mode is selected when the
298 board receives a command packet within the first five seconds
299 of operation; if no packet is received, the board enters
303 At power on, you will hear three beeps or see three flashes
304 ("S" in Morse code for startup) and then a pause while
305 the altimeter completes initialization and self tests, and decides which
309 In flight or "pad" mode, the altimeter engages the flight
310 state machine, goes into transmit-only mode on the RF link
311 sending telemetry, and waits for launch to be detected.
312 Flight mode is indicated by an "di-dah-dah-dit" ("P" for pad)
313 on the beeper or lights, followed by beeps or flashes
314 indicating the state of the pyrotechnic igniter continuity.
315 One beep/flash indicates apogee continuity, two beeps/flashes
316 indicate main continuity, three beeps/flashes indicate both
317 apogee and main continuity, and one longer "brap" sound or
318 rapidly alternating lights indicates no continuity. For a
319 dual deploy flight, make sure you're getting three beeps or
320 flashes before launching! For apogee-only or motor eject
321 flights, do what makes sense.
324 In idle mode, you will hear an audible "di-dit" or see two short flashes ("I" for idle), and
325 the normal flight state machine is disengaged, thus
326 no ejection charges will fire. The altimeters also listen on the RF
327 link when in idle mode for packet mode requests sent from TeleDongle.
328 Commands can be issued to a TeleMetrum in idle mode over either
329 USB or the RF link equivalently. TeleMini uses only the RF link.
330 Idle mode is useful for configuring the altimeter, for extracting data
331 from the on-board storage chip after flight, and for ground testing
335 One "neat trick" of particular value when the altimeter is used with very
336 large airframes, is that you can power the board up while the rocket
337 is horizontal, such that it comes up in idle mode. Then you can
338 raise the airframe to launch position, use a TeleDongle to open
339 a packet connection, and issue a 'reset' command which will cause
340 the altimeter to reboot and come up in
341 flight mode. This is much safer than standing on the top step of a
342 rickety step-ladder or hanging off the side of a launch tower with
343 a screw-driver trying to turn on your avionics before installing
350 TeleMetrum includes a complete GPS receiver. See a later section for
351 a brief explanation of how GPS works that will help you understand
352 the information in the telemetry stream. The bottom line is that
353 the TeleMetrum GPS receiver needs to lock onto at least four
354 satellites to obtain a solid 3 dimensional position fix and know
358 TeleMetrum provides backup power to the GPS chip any time a LiPo
359 battery is connected. This allows the receiver to "warm start" on
360 the launch rail much faster than if every power-on were a "cold start"
361 for the GPS receiver. In typical operations, powering up TeleMetrum
362 on the flight line in idle mode while performing final airframe
363 preparation will be sufficient to allow the GPS receiver to cold
364 start and acquire lock. Then the board can be powered down during
365 RSO review and installation on a launch rod or rail. When the board
366 is turned back on, the GPS system should lock very quickly, typically
367 long before igniter installation and return to the flight line are
372 <title>Ground Testing </title>
374 An important aspect of preparing a rocket using electronic deployment
375 for flight is ground testing the recovery system. Thanks
376 to the bi-directional RF link central to the Altus Metrum system,
377 this can be accomplished in a TeleMetrum- or TeleMini- equipped rocket without as
378 much work as you may be accustomed to with other systems. It can
382 Just prep the rocket for flight, then power up the altimeter
383 in "idle" mode (placing airframe horizontal for TeleMetrum or
384 starting the RF packet connection for TeleMini). This will cause the
385 firmware to go into "idle" mode, in which the normal flight
386 state machine is disabled and charges will not fire without
387 manual command. Then, establish an RF packet connection from
388 a TeleDongle-equipped computer using the P command from a safe
389 distance. You can now command the altimeter to fire the apogee
390 or main charges to complete your testing.
393 In order to reduce the chance of accidental firing of pyrotechnic
394 charges, the command to fire a charge is intentionally somewhat
395 difficult to type, and the built-in help is slightly cryptic to
396 prevent accidental echoing of characters from the help text back at
397 the board from firing a charge. The command to fire the apogee
398 drogue charge is 'i DoIt drogue' and the command to fire the main
399 charge is 'i DoIt main'.
403 <title>Radio Link </title>
405 The chip our boards are based on incorporates an RF transceiver, but
406 it's not a full duplex system... each end can only be transmitting or
407 receiving at any given moment. So we had to decide how to manage the
411 By design, the altimeter firmware listens for an RF connection when
412 it's in "idle mode", which
413 allows us to use the RF link to configure the rocket, do things like
414 ejection tests, and extract data after a flight without having to
415 crack open the airframe. However, when the board is in "flight
416 mode", the altimeter only
417 transmits and doesn't listen at all. That's because we want to put
418 ultimate priority on event detection and getting telemetry out of
419 the rocket and out over
420 the RF link in case the rocket crashes and we aren't able to extract
424 We don't use a 'normal packet radio' mode because they're just too
425 inefficient. The GFSK modulation we use is just FSK with the
426 baseband pulses passed through a
427 Gaussian filter before they go into the modulator to limit the
428 transmitted bandwidth. When combined with the hardware forward error
429 correction support in the cc1111 chip, this allows us to have a very
430 robust 38.4 kilobit data link with only 10 milliwatts of transmit power,
431 a whip antenna in the rocket, and a hand-held Yagi on the ground. We've
432 had flights to above 21k feet AGL with good reception, and calculations
433 suggest we should be good to well over 40k feet AGL with a 5-element yagi on
434 the ground. We hope to fly boards to higher altitudes soon, and would
435 of course appreciate customer feedback on performance in higher
440 <title>Configurable Parameters</title>
442 Configuring an Altus Metrum altimeter for flight is very
443 simple. Through the use of a Kalman filter, there is no need
444 to set a "mach delay" . The few configurable parameters can
445 all be set using a simple terminal program over the USB port
446 or RF link via TeleDongle.
449 <title>Radio Frequencies</title>
451 The Altus Metrum boards support frequencies in the 70cm
452 band. By default, the configuration interface provides a
453 list of 10 common frequencies -- 100kHz channels starting at
454 434.550MHz. However, you can configure the firmware to use
455 any 50kHz multiple within the 70cm band. At any given
456 launch, we highly recommend coordinating who will use each
457 frequency and when to avoid interference. And of course, both
458 altimeter and TeleDongle must be configured to the same
459 frequency to successfully communicate with each other.
462 To set the radio frequency, use the 'c R' command to specify the
463 radio transceiver configuration parameter. This parameter is computed
464 using the desired frequency, 'F', the radio calibration parameter, 'C' (showed by the 'c s' command) and
465 the standard calibration reference frequency, 'S', (normally 434.550Mhz):
469 Round the result to the nearest integer value.
470 As with all 'c' sub-commands, follow this with a 'c w' to write the
471 change to the parameter block in the on-board flash on
472 your altimeter board if you want the change to stay in place across reboots.
476 <title>Apogee Delay</title>
478 Apogee delay is the number of seconds after the altimeter detects flight
479 apogee that the drogue charge should be fired. In most cases, this
480 should be left at the default of 0. However, if you are flying
481 redundant electronics such as for an L3 certification, you may wish
482 to set one of your altimeters to a positive delay so that both
483 primary and backup pyrotechnic charges do not fire simultaneously.
486 To set the apogee delay, use the 'c d' command.
487 As with all 'c' sub-commands, follow this with a 'c w' to write the
488 change to the parameter block in the on-board DataFlash chip.
491 Please note that the Altus Metrum apogee detection algorithm
492 fires exactly at apogee. If you are also flying an
493 altimeter like the PerfectFlite MAWD, which only supports
494 selecting 0 or 1 seconds of apogee delay, you may wish to
495 set the MAWD to 0 seconds delay and set the TeleMetrum to
496 fire your backup 2 or 3 seconds later to avoid any chance of
497 both charges firing simultaneously. We've flown several
498 airframes this way quite happily, including Keith's
503 <title>Main Deployment Altitude</title>
505 By default, the altimeter will fire the main deployment charge at an
506 elevation of 250 meters (about 820 feet) above ground. We think this
507 is a good elevation for most airframes, but feel free to change this
508 to suit. In particular, if you are flying two altimeters, you may
510 deployment elevation for the backup altimeter to be something lower
511 than the primary so that both pyrotechnic charges don't fire
515 To set the main deployment altitude, use the 'c m' command.
516 As with all 'c' sub-commands, follow this with a 'c w' to write the
517 change to the parameter block in the on-board DataFlash chip.
522 <title>Calibration</title>
524 There are only two calibrations required for a TeleMetrum board, and
525 only one for TeleDongle and TeleMini.
528 <title>Radio Frequency</title>
530 The radio frequency is synthesized from a clock based on the 48 Mhz
531 crystal on the board. The actual frequency of this oscillator must be
532 measured to generate a calibration constant. While our GFSK modulation
533 bandwidth is wide enough to allow boards to communicate even when
534 their oscillators are not on exactly the same frequency, performance
535 is best when they are closely matched.
536 Radio frequency calibration requires a calibrated frequency counter.
537 Fortunately, once set, the variation in frequency due to aging and
538 temperature changes is small enough that re-calibration by customers
539 should generally not be required.
542 To calibrate the radio frequency, connect the UHF antenna port to a
543 frequency counter, set the board to 434.550MHz, and use the 'C'
544 command to generate a CW carrier. Wait for the transmitter temperature
545 to stabilize and the frequency to settle down.
546 Then, divide 434.550 Mhz by the
547 measured frequency and multiply by the current radio cal value show
548 in the 'c s' command. For an unprogrammed board, the default value
549 is 1186611. Take the resulting integer and program it using the 'c f'
550 command. Testing with the 'C' command again should show a carrier
551 within a few tens of Hertz of the intended frequency.
552 As with all 'c' sub-commands, follow this with a 'c w' to write the
553 change to the parameter block in the on-board DataFlash chip.
556 when the radio calibration value is changed, the radio
557 frequency value is reset to the same value, so you'll need
558 to recompute and reset the radio frequency value using the
559 new radio calibration value.
563 <title>TeleMetrum Accelerometer</title>
565 The TeleMerum accelerometer we use has its own 5 volt power supply and
566 the output must be passed through a resistive voltage divider to match
567 the input of our 3.3 volt ADC. This means that unlike the barometric
568 sensor, the output of the acceleration sensor is not ratiometric to
569 the ADC converter, and calibration is required. We also support the
570 use of any of several accelerometers from a Freescale family that
571 includes at least +/- 40g, 50g, 100g, and 200g parts. Using gravity,
572 a simple 2-point calibration yields acceptable results capturing both
573 the different sensitivities and ranges of the different accelerometer
574 parts and any variation in power supply voltages or resistor values
575 in the divider network.
578 To calibrate the acceleration sensor, use the 'c a 0' command. You
579 will be prompted to orient the board vertically with the UHF antenna
580 up and press a key, then to orient the board vertically with the
581 UHF antenna down and press a key.
582 As with all 'c' sub-commands, follow this with a 'c w' to write the
583 change to the parameter block in the on-board DataFlash chip.
586 The +1g and -1g calibration points are included in each telemetry
587 frame and are part of the header extracted by ao-dumplog after flight.
588 Note that we always store and return raw ADC samples for each
589 sensor... nothing is permanently "lost" or "damaged" if the
593 In the unlikely event an accel cal that goes badly, it is possible
594 that TeleMetrum may always come up in 'pad mode' and as such not be
595 listening to either the USB or radio interfaces. If that happens,
596 there is a special hook in the firmware to force the board back
597 in to 'idle mode' so you can re-do the cal. To use this hook, you
598 just need to ground the SPI clock pin at power-on. This pin is
599 available as pin 2 on the 8-pin companion connector, and pin 1 is
600 ground. So either carefully install a fine-gauge wire jumper
601 between the two pins closest to the index hole end of the 8-pin
602 connector, or plug in the programming cable to the 8-pin connector
603 and use a small screwdriver or similar to short the two pins closest
604 to the index post on the 4-pin end of the programming cable, and
605 power up the board. It should come up in 'idle mode' (two beeps).
610 <title>Updating Device Firmware</title>
612 The big conceptual thing to realize is that you have to use a
613 TeleDongle as a programmer to update a TeleMetrum or TeleMini,
614 and a TeleMetrum or other TeleDongle to program the TeleDongle
615 Due to limited memory resources in the cc1111, we don't support
616 programming directly over USB.
619 You may wish to begin by ensuring you have current firmware images.
620 These are distributed as part of the AltOS software bundle that
621 also includes the AltosUI ground station program. Newer ground
622 station versions typically work fine with older firmware versions,
623 so you don't need to update your devices just to try out new
624 software features. You can always download the most recent
625 version from <ulink url="http://www.altusmetrum.org/AltOS/"/>.
628 We recommend updating the altimeter first, before updating TeleDongle.
631 <title>Updating TeleMetrum Firmware</title>
632 <orderedlist inheritnum='inherit' numeration='arabic'>
634 Find the 'programming cable' that you got as part of the starter
635 kit, that has a red 8-pin MicroMaTch connector on one end and a
636 red 4-pin MicroMaTch connector on the other end.
639 Take the 2 screws out of the TeleDongle case to get access
640 to the circuit board.
643 Plug the 8-pin end of the programming cable to the
644 matching connector on the TeleDongle, and the 4-pin end to the
645 matching connector on the TeleMetrum.
646 Note that each MicroMaTch connector has an alignment pin that
647 goes through a hole in the PC board when you have the cable
651 Attach a battery to the TeleMetrum board.
654 Plug the TeleDongle into your computer's USB port, and power
658 Run AltosUI, and select 'Flash Image' from the File menu.
661 Pick the TeleDongle device from the list, identifying it as the
665 Select the image you want put on the TeleMetrum, which should have a
666 name in the form telemetrum-v1.1-1.0.0.ihx. It should be visible
667 in the default directory, if not you may have to poke around
668 your system to find it.
671 Make sure the configuration parameters are reasonable
672 looking. If the serial number and/or RF configuration
673 values aren't right, you'll need to change them.
676 Hit the 'OK' button and the software should proceed to flash
677 the TeleMetrum with new firmware, showing a progress bar.
680 Confirm that the TeleMetrum board seems to have updated ok, which you
681 can do by plugging in to it over USB and using a terminal program
682 to connect to the board and issue the 'v' command to check
686 If something goes wrong, give it another try.
691 <title>Updating TeleMini Firmware</title>
692 <orderedlist inheritnum='inherit' numeration='arabic'>
694 You'll need a special 'programming cable' to reprogram the
695 TeleMini. It's available on the Altus Metrum web store, or
696 you can make your own using an 8-pin MicroMaTch connector on
697 one end and a set of four pins on the other.
700 Take the 2 screws out of the TeleDongle case to get access
701 to the circuit board.
704 Plug the 8-pin end of the programming cable to the matching
705 connector on the TeleDongle, and the 4-pins into the holes
706 in the TeleMini circuit board. Note that the MicroMaTch
707 connector has an alignment pin that goes through a hole in
708 the PC board when you have the cable oriented correctly, and
709 that pin 1 on the TeleMini board is marked with a square pad
710 while the other pins have round pads.
713 Attach a battery to the TeleMini board.
716 Plug the TeleDongle into your computer's USB port, and power
720 Run AltosUI, and select 'Flash Image' from the File menu.
723 Pick the TeleDongle device from the list, identifying it as the
727 Select the image you want put on the TeleMini, which should have a
728 name in the form telemini-v1.0-1.0.0.ihx. It should be visible
729 in the default directory, if not you may have to poke around
730 your system to find it.
733 Make sure the configuration parameters are reasonable
734 looking. If the serial number and/or RF configuration
735 values aren't right, you'll need to change them.
738 Hit the 'OK' button and the software should proceed to flash
739 the TeleMini with new firmware, showing a progress bar.
742 Confirm that the TeleMini board seems to have updated ok, which you
743 can do by configuring it over the RF link through the TeleDongle, or
744 letting it come up in "flight" mode and listening for telemetry.
747 If something goes wrong, give it another try.
752 <title>Updating TeleDongle Firmware</title>
754 Updating TeleDongle's firmware is just like updating TeleMetrum or TeleMini
755 firmware, but you use either a TeleMetrum or another TeleDongle as the programmer.
757 <orderedlist inheritnum='inherit' numeration='arabic'>
759 Find the 'programming cable' that you got as part of the starter
760 kit, that has a red 8-pin MicroMaTch connector on one end and a
761 red 4-pin MicroMaTch connector on the other end.
764 Find the USB cable that you got as part of the starter kit, and
765 plug the "mini" end in to the mating connector on TeleMetrum or TeleDongle.
768 Take the 2 screws out of the TeleDongle case to get access
769 to the circuit board.
772 Plug the 8-pin end of the programming cable to the
773 matching connector on the programmer, and the 4-pin end to the
774 matching connector on the TeleDongle.
775 Note that each MicroMaTch connector has an alignment pin that
776 goes through a hole in the PC board when you have the cable
780 Attach a battery to the TeleMetrum board if you're using one.
783 Plug both the programmer and the TeleDongle into your computer's USB
784 ports, and power up the programmer.
787 Run AltosUI, and select 'Flash Image' from the File menu.
790 Pick the programmer device from the list, identifying it as the
794 Select the image you want put on the TeleDongle, which should have a
795 name in the form teledongle-v0.2-1.0.0.ihx. It should be visible
796 in the default directory, if not you may have to poke around
797 your system to find it.
800 Make sure the configuration parameters are reasonable
801 looking. If the serial number and/or RF configuration
802 values aren't right, you'll need to change them. The TeleDongle
803 serial number is on the "bottom" of the circuit board, and can
804 usually be read through the translucent blue plastic case without
805 needing to remove the board from the case.
808 Hit the 'OK' button and the software should proceed to flash
809 the TeleDongle with new firmware, showing a progress bar.
812 Confirm that the TeleDongle board seems to have updated ok, which you
813 can do by plugging in to it over USB and using a terminal program
814 to connect to the board and issue the 'v' command to check
815 the version, etc. Once you're happy, remove the programming cable
816 and put the cover back on the TeleDongle.
819 If something goes wrong, give it another try.
823 Be careful removing the programming cable from the locking 8-pin
824 connector on TeleMetrum. You'll need a fingernail or perhaps a thin
825 screwdriver or knife blade to gently pry the locking ears out
826 slightly to extract the connector. We used a locking connector on
827 TeleMetrum to help ensure that the cabling to companion boards
828 used in a rocket don't ever come loose accidentally in flight.
836 <title>AltosUI</title>
838 The AltosUI program provides a graphical user interface for
839 interacting with the Altus Metrum product family, including
840 TeleMetrum, TeleMini and TeleDongle. AltosUI can monitor telemetry data,
841 configure TeleMetrum, TeleMini and TeleDongle devices and many other
842 tasks. The primary interface window provides a selection of
843 buttons, one for each major activity in the system. This manual
844 is split into chapters, each of which documents one of the tasks
845 provided from the top-level toolbar.
848 <title>Monitor Flight</title>
849 <subtitle>Receive, Record and Display Telemetry Data</subtitle>
851 Selecting this item brings up a dialog box listing all of the
852 connected TeleDongle devices. When you choose one of these,
853 AltosUI will create a window to display telemetry data as
854 received by the selected TeleDongle device.
857 All telemetry data received are automatically recorded in
858 suitable log files. The name of the files includes the current
859 date and rocket serial and flight numbers.
862 The radio frequency being monitored by the TeleDongle device is
863 displayed at the top of the window. You can configure the
864 frequecy by clicking on the frequency box and selecting the desired
865 frequency. AltosUI remembers the last frequency selected for each
866 TeleDongle and selects that automatically the next time you use
870 Below the TeleDongle frequency selector, the window contains a few
871 significant pieces of information about the altimeter providing
872 the telemetry data stream:
876 <para>The configured callsign</para>
879 <para>The device serial number</para>
882 <para>The flight number. Each altimeter remembers how many
888 The rocket flight state. Each flight passes through several
889 states including Pad, Boost, Fast, Coast, Drogue, Main and
895 The Received Signal Strength Indicator value. This lets
896 you know how strong a signal TeleDongle is receiving. The
897 radio inside TeleDongle operates down to about -99dBm;
898 weaker signals may not be receiveable. The packet link uses
899 error correction and detection techniques which prevent
900 incorrect data from being reported.
905 Finally, the largest portion of the window contains a set of
906 tabs, each of which contain some information about the rocket.
907 They're arranged in 'flight order' so that as the flight
908 progresses, the selected tab automatically switches to display
909 data relevant to the current state of the flight. You can select
910 other tabs at any time. The final 'table' tab contains all of
911 the telemetry data in one place.
914 <title>Launch Pad</title>
916 The 'Launch Pad' tab shows information used to decide when the
917 rocket is ready for flight. The first elements include red/green
918 indicators, if any of these is red, you'll want to evaluate
919 whether the rocket is ready to launch:
923 Battery Voltage. This indicates whether the LiPo battery
924 powering the TeleMetrum has sufficient charge to last for
925 the duration of the flight. A value of more than
926 3.7V is required for a 'GO' status.
931 Apogee Igniter Voltage. This indicates whether the apogee
932 igniter has continuity. If the igniter has a low
933 resistance, then the voltage measured here will be close
934 to the LiPo battery voltage. A value greater than 3.2V is
935 required for a 'GO' status.
940 Main Igniter Voltage. This indicates whether the main
941 igniter has continuity. If the igniter has a low
942 resistance, then the voltage measured here will be close
943 to the LiPo battery voltage. A value greater than 3.2V is
944 required for a 'GO' status.
949 GPS Locked. For a TeleMetrum device, this indicates whether the GPS receiver is
950 currently able to compute position information. GPS requires
951 at least 4 satellites to compute an accurate position.
956 GPS Ready. For a TeleMetrum device, this indicates whether GPS has reported at least
957 10 consecutive positions without losing lock. This ensures
958 that the GPS receiver has reliable reception from the
964 The LaunchPad tab also shows the computed launch pad position
965 and altitude, averaging many reported positions to improve the
971 <title>Ascent</title>
973 This tab is shown during Boost, Fast and Coast
974 phases. The information displayed here helps monitor the
975 rocket as it heads towards apogee.
978 The height, speed and acceleration are shown along with the
979 maxium values for each of them. This allows you to quickly
980 answer the most commonly asked questions you'll hear during
984 The current latitude and longitude reported by the TeleMetrum GPS are
985 also shown. Note that under high acceleration, these values
986 may not get updated as the GPS receiver loses position
987 fix. Once the rocket starts coasting, the receiver should
988 start reporting position again.
991 Finally, the current igniter voltages are reported as in the
992 Launch Pad tab. This can help diagnose deployment failures
993 caused by wiring which comes loose under high acceleration.
997 <title>Descent</title>
999 Once the rocket has reached apogee and (we hope) activated the
1000 apogee charge, attention switches to tracking the rocket on
1001 the way back to the ground, and for dual-deploy flights,
1002 waiting for the main charge to fire.
1005 To monitor whether the apogee charge operated correctly, the
1006 current descent rate is reported along with the current
1007 height. Good descent rates generally range from 15-30m/s.
1010 For TeleMetrum altimeters, you can locate the rocket in the sky
1011 using the elevation and
1012 bearing information to figure out where to look. Elevation is
1013 in degrees above the horizon. Bearing is reported in degrees
1014 relative to true north. Range can help figure out how big the
1015 rocket will appear. Note that all of these values are relative
1016 to the pad location. If the elevation is near 90°, the rocket
1017 is over the pad, not over you.
1020 Finally, the igniter voltages are reported in this tab as
1021 well, both to monitor the main charge as well as to see what
1022 the status of the apogee charge is.
1026 <title>Landed</title>
1028 Once the rocket is on the ground, attention switches to
1029 recovery. While the radio signal is generally lost once the
1030 rocket is on the ground, the last reported GPS position is
1031 generally within a short distance of the actual landing location.
1034 The last reported GPS position is reported both by
1035 latitude and longitude as well as a bearing and distance from
1036 the launch pad. The distance should give you a good idea of
1037 whether you'll want to walk or hitch a ride. Take the reported
1038 latitude and longitude and enter them into your handheld GPS
1039 unit and have that compute a track to the landing location.
1042 Both TeleMini and TeleMetrum will continue to transmit RDF
1043 tones after landing, allowing you to locate the rocket by
1044 following the radio signal. You may need to get away from
1045 the clutter of the flight line, or even get up on a hill (or
1046 your neighbor's RV) to receive the RDF signal.
1049 The maximum height, speed and acceleration reported
1050 during the flight are displayed for your admiring observers.
1053 To get more detailed information about the flight, you can
1054 click on the 'Graph Flight' button which will bring up a
1055 graph window for the current flight.
1059 <title>Site Map</title>
1061 When the TeleMetrum gets a GPS fix, the Site Map tab will map
1062 the rocket's position to make it easier for you to locate the
1063 rocket, both while it is in the air, and when it has landed. The
1064 rocket's state is indicated by colour: white for pad, red for
1065 boost, pink for fast, yellow for coast, light blue for drogue,
1066 dark blue for main, and black for landed.
1069 The map's scale is approximately 3m (10ft) per pixel. The map
1070 can be dragged using the left mouse button. The map will attempt
1071 to keep the rocket roughly centred while data is being received.
1074 Images are fetched automatically via the Google Maps Static API,
1075 and are cached for reuse. If map images cannot be downloaded,
1076 the rocket's path will be traced on a dark grey background
1080 You can pre-load images for your favorite launch sites
1081 before you leave home; check out the 'Preload Maps' section below.
1086 <title>Packet Command Mode</title>
1087 <subtitle>Controlling An Altimeter Over The Radio Link</subtitle>
1089 One of the unique features of the Altus Metrum environment is
1090 the ability to create a two way command link between TeleDongle
1091 and an altimeter using the digital radio transceivers built into
1092 each device. This allows you to interact with the altimeter from
1093 afar, as if it were directly connected to the computer.
1096 Any operation which can be performed with TeleMetrum
1097 can either be done with TeleMetrum directly connected to
1098 the computer via the USB cable, or through the packet
1099 link. Simply select the appropriate TeleDongle device when
1100 the list of devices is presented and AltosUI will use packet
1104 One oddity in the current interface is how AltosUI selects the
1105 frequency for packet mode communications. Instead of providing
1106 an interface to specifically configure the frequency, it uses
1107 whatever frequency was most recently selected for the target
1108 TeleDongle device in Monitor Flight mode. If you haven't ever
1109 used that mode with the TeleDongle in question, select the
1110 Monitor Flight button from the top level UI, pick the
1111 appropriate TeleDongle device. Once the flight monitoring
1112 window is open, select the desired frequency and then close it
1113 down again. All Packet Command Mode operations will now use
1119 Save Flight Data—Recover flight data from the rocket without
1125 Configure altimeter apogee delays or main deploy heights
1126 to respond to changing launch conditions. You can also
1127 'reboot' the altimeter. Use this to remotely enable the
1128 flight computer by turning TeleMetrum on in "idle" mode,
1129 then once the airframe is oriented for launch, you can
1130 reboot the altimeter and have it restart in pad mode
1131 without having to climb the scary ladder.
1136 Fire Igniters—Test your deployment charges without snaking
1137 wires out through holes in the airframe. Simply assembly the
1138 rocket as if for flight with the apogee and main charges
1139 loaded, then remotely command the altimeter to fire the
1145 Packet command mode uses the same RF frequencies as telemetry
1146 mode. Configure the desired TeleDongle frequency using the
1147 flight monitor window frequency selector and then close that
1148 window before performing the desired operation.
1151 TeleMetrum only enables packet command mode in 'idle' mode, so
1152 make sure you have TeleMetrum lying horizontally when you turn
1153 it on. Otherwise, TeleMetrum will start in 'pad' mode ready for
1154 flight and will not be listening for command packets from TeleDongle.
1157 TeleMini listens for a command packet for five seconds after
1158 first being turned on, if it doesn't hear anything, it enters
1159 'pad' mode, ready for flight and will no longer listen for
1163 When packet command mode is enabled, you can monitor the link
1164 by watching the lights on the
1165 devices. The red LED will flash each time they
1166 transmit a packet while the green LED will light up
1167 on TeleDongle while it is waiting to receive a packet from
1172 <title>Save Flight Data</title>
1174 The altimeter records flight data to its internal flash memory.
1175 The TeleMetrum data is recorded at a much higher rate than the telemetry
1176 system can handle, and is not subject to radio drop-outs. As
1177 such, it provides a more complete and precise record of the
1178 flight. The 'Save Flight Data' button allows you to read the
1179 flash memory and write it to disk. As TeleMini has only a barometer, it
1180 records data at the same rate as the telemetry signal, but there will be
1181 no data lost due to telemetry drop-outs.
1184 Clicking on the 'Save Flight Data' button brings up a list of
1185 connected TeleMetrum and TeleDongle devices. If you select a
1186 TeleMetrum device, the flight data will be downloaded from that
1187 device directly. If you select a TeleDongle device, flight data
1188 will be downloaded from a TeleMetrum or TeleMini device connected via the
1189 packet command link to the specified TeleDongle. See the chapter
1190 on Packet Command Mode for more information about this.
1193 After the device has been selected, a dialog showing the
1194 flight data saved in the device will be shown allowing you to
1195 select which flights to download and which to delete. With
1196 version 0.9 or newer firmware, you must erase flights in order
1197 for the space they consume to be reused by another
1198 flight. This prevents you from accidentally losing flight data
1199 if you neglect to download data before flying again. Note that
1200 if there is no more space available in the device, then no
1201 data will be recorded for a flight.
1204 The filename for each flight log is computed automatically
1205 from the recorded flight date, altimeter serial number and
1206 flight number information.
1210 <title>Replay Flight</title>
1212 Select this button and you are prompted to select a flight
1213 record file, either a .telem file recording telemetry data or a
1214 .eeprom file containing flight data saved from the altimeter
1218 Once a flight record is selected, the flight monitor interface
1219 is displayed and the flight is re-enacted in real time. Check
1220 the Monitor Flight chapter above to learn how this window operates.
1224 <title>Graph Data</title>
1226 Select this button and you are prompted to select a flight
1227 record file, either a .telem file recording telemetry data or a
1228 .eeprom file containing flight data saved from
1232 Once a flight record is selected, a window with two tabs is
1233 opened. The first tab contains a graph with acceleration
1234 (blue), velocity (green) and altitude (red) of the flight are
1235 plotted and displayed, measured in metric units. The
1236 apogee(yellow) and main(magenta) igniter voltages are also
1237 displayed; high voltages indicate continuity, low voltages
1238 indicate open circuits. The second tab contains some basic
1242 The graph can be zoomed into a particular area by clicking and
1243 dragging down and to the right. Once zoomed, the graph can be
1244 reset by clicking and dragging up and to the left. Holding down
1245 control and clicking and dragging allows the graph to be panned.
1246 The right mouse button causes a popup menu to be displayed, giving
1247 you the option save or print the plot.
1250 Note that telemetry files will generally produce poor graphs
1251 due to the lower sampling rate and missed telemetry packets.
1252 Use saved flight data for graphing where possible.
1256 <title>Export Data</title>
1258 This tool takes the raw data files and makes them available for
1259 external analysis. When you select this button, you are prompted to select a flight
1260 data file (either .eeprom or .telem will do, remember that
1261 .eeprom files contain higher resolution and more continuous
1262 data). Next, a second dialog appears which is used to select
1263 where to write the resulting file. It has a selector to choose
1264 between CSV and KML file formats.
1267 <title>Comma Separated Value Format</title>
1269 This is a text file containing the data in a form suitable for
1270 import into a spreadsheet or other external data analysis
1271 tool. The first few lines of the file contain the version and
1272 configuration information from the altimeter, then
1273 there is a single header line which labels all of the
1274 fields. All of these lines start with a '#' character which
1275 most tools can be configured to skip over.
1278 The remaining lines of the file contain the data, with each
1279 field separated by a comma and at least one space. All of
1280 the sensor values are converted to standard units, with the
1281 barometric data reported in both pressure, altitude and
1282 height above pad units.
1286 <title>Keyhole Markup Language (for Google Earth)</title>
1288 This is the format used by
1289 Googleearth to provide an overlay within that
1290 application. With this, you can use Googleearth to see the
1291 whole flight path in 3D.
1296 <title>Configure Altimeter</title>
1298 Select this button and then select either a TeleMetrum or
1299 TeleDongle Device from the list provided. Selecting a TeleDongle
1300 device will use Packet Comamnd Mode to configure a remote
1301 altimeter. Learn how to use this in the Packet Command
1305 The first few lines of the dialog provide information about the
1306 connected device, including the product name,
1307 software version and hardware serial number. Below that are the
1308 individual configuration entries.
1311 At the bottom of the dialog, there are four buttons:
1316 Save. This writes any changes to the
1317 configuration parameter block in flash memory. If you don't
1318 press this button, any changes you make will be lost.
1323 Reset. This resets the dialog to the most recently saved values,
1324 erasing any changes you have made.
1329 Reboot. This reboots the device. Use this to
1330 switch from idle to pad mode by rebooting once the rocket is
1331 oriented for flight.
1336 Close. This closes the dialog. Any unsaved changes will be
1342 The rest of the dialog contains the parameters to be configured.
1345 <title>Main Deploy Altitude</title>
1347 This sets the altitude (above the recorded pad altitude) at
1348 which the 'main' igniter will fire. The drop-down menu shows
1349 some common values, but you can edit the text directly and
1350 choose whatever you like. If the apogee charge fires below
1351 this altitude, then the main charge will fire two seconds
1352 after the apogee charge fires.
1356 <title>Apogee Delay</title>
1358 When flying redundant electronics, it's often important to
1359 ensure that multiple apogee charges don't fire at precisely
1360 the same time as that can overpressurize the apogee deployment
1361 bay and cause a structural failure of the airframe. The Apogee
1362 Delay parameter tells the flight computer to fire the apogee
1363 charge a certain number of seconds after apogee has been
1368 <title>Radio Frequency</title>
1370 This configures which of the configured frequencies to use for both
1371 telemetry and packet command mode. Note that if you set this
1372 value via packet command mode, you will have to reconfigure
1373 the TeleDongle frequency before you will be able to use packet
1378 <title>Radio Calibration</title>
1380 The radios in every Altus Metrum device are calibrated at the
1381 factory to ensure that they transmit and receive on the
1382 specified frequency. You can adjust that
1383 calibration by changing this value. To change the TeleDongle's
1384 calibration, you must reprogram the unit completely.
1388 <title>Callsign</title>
1390 This sets the callsign included in each telemetry packet. Set this
1391 as needed to conform to your local radio regulations.
1395 <title>Maximum Flight Log Size</title>
1397 This sets the space (in kilobytes) allocated for each flight
1398 log. The available space will be divided into chunks of this
1399 size. A smaller value will allow more flights to be stored,
1400 a larger value will record data from longer flights.
1403 During ascent, TeleMetrum records barometer and
1404 accelerometer values 100 times per second, other analog
1405 information (voltages and temperature) 6 times per second
1406 and GPS data once per second. During descent, the non-GPS
1407 data is recorded 1/10th as often. Each barometer +
1408 accelerometer record takes 8 bytes.
1411 The default, 192kB, will store over 200 seconds of data at
1412 the ascent rate, or over 2000 seconds of data at the descent
1413 rate. That's plenty for most flights. This leaves enough
1414 storage for five flights in a 1MB system, or 10 flights in a
1418 The configuration block takes the last available block of
1419 memory, on v1.0 boards that's just 256 bytes. However, the
1420 flash part on the v1.1 boards uses 64kB for each block.
1423 TeleMini has 5kB of on-board storage, which is plenty for a
1424 single flight. Make sure you download and delete the data
1425 before a subsequent flight or it will not log any data.
1429 <title>Ignite Mode</title>
1431 TeleMetrum and TeleMini provide two igniter channels as they
1432 were originally designed as dual-deploy flight
1433 computers. This configuration parameter allows the two
1434 channels to be used in different configurations.
1439 Dual Deploy. This is the usual mode of operation; the
1440 'apogee' channel is fired at apogee and the 'main'
1441 channel at the height above ground specified by the
1442 'Main Deploy Altitude' during descent.
1447 Redundant Apogee. This fires both channels at
1448 apogee, the 'apogee' channel first followed after a two second
1449 delay by the 'main' channel.
1454 Redundant Main. This fires both channels at the
1455 height above ground specified by the Main Deploy
1456 Altitude setting during descent. The 'apogee'
1457 channel is fired first, followed after a two second
1458 delay by the 'main' channel.
1464 <title>Pad Orientation</title>
1466 Because it includes an accelerometer, TeleMetrum is
1467 sensitive to the orientation of the board. By default, it
1468 expects the antenna end to point forward. This parameter
1469 allows that default to be changed, permitting the board to
1470 be mounted with the antenna pointing aft instead.
1475 Antenna Up. In this mode, the antenna end of the
1476 TeleMetrum board must point forward, in line with the
1477 expected flight path.
1482 Antenna Down. In this mode, the antenna end of the
1483 TeleMetrum board must point aft, in line with the
1484 expected flight path.
1491 <title>Configure AltosUI</title>
1493 This button presents a dialog so that you can configure the AltosUI global settings.
1496 <title>Voice Settings</title>
1498 AltosUI provides voice annoucements during flight so that you
1499 can keep your eyes on the sky and still get information about
1500 the current flight status. However, sometimes you don't want
1505 <para>Enable—turns all voice announcements on and off</para>
1509 Test Voice—Plays a short message allowing you to verify
1510 that the audio systme is working and the volume settings
1517 <title>Log Directory</title>
1519 AltosUI logs all telemetry data and saves all TeleMetrum flash
1520 data to this directory. This directory is also used as the
1521 staring point when selecting data files for display or export.
1524 Click on the directory name to bring up a directory choosing
1525 dialog, select a new directory and click 'Select Directory' to
1526 change where AltosUI reads and writes data files.
1530 <title>Callsign</title>
1532 This value is used in command packet mode and is transmitted
1533 in each packet sent from TeleDongle and received from
1534 TeleMetrum. It is not used in telemetry mode as that transmits
1535 packets only from TeleMetrum to TeleDongle. Configure this
1536 with the AltosUI operators callsign as needed to comply with
1537 your local radio regulations.
1541 <title>Serial Debug</title>
1543 This causes all communication with a connected device to be
1544 dumped to the console from which AltosUI was started. If
1545 you've started it from an icon or menu entry, the output
1546 will simply be discarded. This mode can be useful to debug
1547 various serial communication issues.
1551 <title>Manage Frequencies</title>
1553 This brings up a dialog where you can configure the set of
1554 frequencies shown in the various frequency menus. You can
1555 add as many as you like, or even reconfigure the default
1556 set. Changing this list does not affect the frequency
1557 settings of any devices, it only changes the set of
1558 frequencies shown in the menus.
1563 <title>Flash Image</title>
1565 This reprograms any Altus Metrum device by using a TeleMetrum
1566 or TeleDongle as a programming dongle. Please read the
1567 directions for flashing devices in the Updating Device
1568 Firmware section above
1571 Once you have the programmer and target devices connected,
1572 push the 'Flash Image' button. That will present a dialog box
1573 listing all of the connected devices. Carefully select the
1574 programmer device, not the device to be programmed.
1577 Next, select the image to flash to the device. These are named
1578 with the product name and firmware version. The file selector
1579 will start in the directory containing the firmware included
1580 with the AltosUI package. Navigate to the directory containing
1581 the desired firmware if it isn't there.
1584 Next, a small dialog containing the device serial number and
1585 RF calibration values should appear. If these values are
1586 incorrect (possibly due to a corrupted image in the device),
1587 enter the correct values here.
1590 Finally, a dialog containing a progress bar will follow the
1591 programming process.
1594 When programming is complete, the target device will
1595 reboot. Note that if the target device is connected via USB, you
1596 will have to unplug it and then plug it back in for the USB
1597 connection to reset so that you can communicate with the device
1602 <title>Fire Igniter</title>
1604 This activates the igniter circuits in TeleMetrum to help test
1605 recovery systems deployment. Because this command can operate
1606 over the Packet Command Link, you can prepare the rocket as
1607 for flight and then test the recovery system without needing
1608 to snake wires inside the airframe.
1611 Selecting the 'Fire Igniter' button brings up the usual device
1612 selection dialog. Pick the desired TeleDongle or TeleMetrum
1613 device. This brings up another window which shows the current
1614 continutity test status for both apogee and main charges.
1617 Next, select the desired igniter to fire. This will enable the
1621 Select the 'Arm' button. This enables the 'Fire' button. The
1622 word 'Arm' is replaced by a countdown timer indicating that
1623 you have 10 seconds to press the 'Fire' button or the system
1624 will deactivate, at which point you start over again at
1625 selecting the desired igniter.
1629 <title>Scan Channels</title>
1631 This listens for telemetry packets on all of the configured
1632 frequencies, displaying information about each device it
1633 receives a packet from. You can select which of the three
1634 telemetry formats should be tried; by default, it only listens
1635 for the standard telemetry packets used in v1.0 and later
1640 <title>Load Maps</title>
1642 Before heading out to a new launch site, you can use this to
1643 load satellite images in case you don't have internet
1644 connectivity at the site. This loads a fairly large area
1645 around the launch site, which should cover any flight you're likely to make.
1648 There's a drop-down menu of launch sites we know about; if
1649 your favorites aren't there, please let us know the lat/lon
1650 and name of the site. The contents of this list are actually
1651 downloaded at run-time, so as new sites are sent in, they'll
1652 get automatically added to this list.
1655 If the launch site isn't in the list, you can manually enter the lat/lon values
1658 Clicking the 'Load Map' button will fetch images from Google
1659 Maps; note that Google limits how many images you can fetch at
1660 once, so if you load more than one launch site, you may get
1661 some gray areas in the map which indicate that Google is tired
1662 of sending data to you. Try again later.
1666 <title>Monitor Idle</title>
1668 This brings up a dialog similar to the Monitor Flight UI,
1669 except it works with the altimeter in "idle" mode by sending
1670 query commands to discover the current state rather than
1671 listening for telemetry packets.
1676 <title>Using Altus Metrum Products</title>
1678 <title>Being Legal</title>
1680 First off, in the US, you need an <ulink url="http://www.altusmetrum.org/Radio/">amateur radio license</ulink> or
1681 other authorization to legally operate the radio transmitters that are part
1686 <title>In the Rocket</title>
1688 In the rocket itself, you just need a <ulink url="http://www.altusmetrum.org/TeleMetrum/">TeleMetrum</ulink> or
1689 <ulink url="http://www.altusmetrum.org/TeleMini/">TeleMini</ulink> board and
1690 a LiPo rechargeable battery. An 860mAh battery weighs less than a 9V
1691 alkaline battery, and will run a TeleMetrum for hours.
1692 A 110mAh battery weighs less than a triple A battery and will run a TeleMetrum for
1693 a few hours, or a TeleMini for much (much) longer.
1696 By default, we ship the altimeters with a simple wire antenna. If your
1697 electronics bay or the airframe it resides within is made of carbon fiber,
1698 which is opaque to RF signals, you may choose to have an SMA connector
1699 installed so that you can run a coaxial cable to an antenna mounted
1700 elsewhere in the rocket.
1704 <title>On the Ground</title>
1706 To receive the data stream from the rocket, you need an antenna and short
1707 feedline connected to one of our <ulink url="http://www.altusmetrum.org/TeleDongle/">TeleDongle</ulink> units. The
1708 TeleDongle in turn plugs directly into the USB port on a notebook
1709 computer. Because TeleDongle looks like a simple serial port, your computer
1710 does not require special device drivers... just plug it in.
1713 The GUI tool, AltosUI, is written in Java and runs across
1714 Linux, Mac OS and Windows. There's also a suite of C tools
1715 for Linux which can perform most of the same tasks.
1718 After the flight, you can use the RF link to extract the more detailed data
1719 logged in either TeleMetrum or TeleMini devices, or you can use a mini USB cable to plug into the
1720 TeleMetrum board directly. Pulling out the data without having to open up
1721 the rocket is pretty cool! A USB cable is also how you charge the LiPo
1722 battery, so you'll want one of those anyway... the same cable used by lots
1723 of digital cameras and other modern electronic stuff will work fine.
1726 If your TeleMetrum-equiped rocket lands out of sight, you may enjoy having a hand-held GPS
1727 receiver, so that you can put in a waypoint for the last reported rocket
1728 position before touch-down. This makes looking for your rocket a lot like
1729 Geo-Cacheing... just go to the waypoint and look around starting from there.
1732 You may also enjoy having a ham radio "HT" that covers the 70cm band... you
1733 can use that with your antenna to direction-find the rocket on the ground
1734 the same way you can use a Walston or Beeline tracker. This can be handy
1735 if the rocket is hiding in sage brush or a tree, or if the last GPS position
1736 doesn't get you close enough because the rocket dropped into a canyon, or
1737 the wind is blowing it across a dry lake bed, or something like that... Keith
1738 and Bdale both currently own and use the Yaesu VX-7R at launches.
1741 So, to recap, on the ground the hardware you'll need includes:
1742 <orderedlist inheritnum='inherit' numeration='arabic'>
1744 an antenna and feedline
1753 optionally, a handheld GPS receiver
1756 optionally, an HT or receiver covering 435 Mhz
1761 The best hand-held commercial directional antennas we've found for radio
1762 direction finding rockets are from
1763 <ulink url="http://www.arrowantennas.com/" >
1766 The 440-3 and 440-5 are both good choices for finding a
1767 TeleMetrum- or TeleMini- equipped rocket when used with a suitable 70cm HT.
1771 <title>Data Analysis</title>
1773 Our software makes it easy to log the data from each flight, both the
1774 telemetry received over the RF link during the flight itself, and the more
1775 complete data log recorded in the flash memory on the altimeter
1776 board. Once this data is on your computer, our postflight tools make it
1777 easy to quickly get to the numbers everyone wants, like apogee altitude,
1778 max acceleration, and max velocity. You can also generate and view a
1779 standard set of plots showing the altitude, acceleration, and
1780 velocity of the rocket during flight. And you can even export a TeleMetrum data file
1781 useable with Google Maps and Google Earth for visualizing the flight path
1782 in two or three dimensions!
1785 Our ultimate goal is to emit a set of files for each flight that can be
1786 published as a web page per flight, or just viewed on your local disk with
1791 <title>Future Plans</title>
1793 In the future, we intend to offer "companion boards" for the rocket that will
1794 plug in to TeleMetrum to collect additional data, provide more pyro channels,
1795 and so forth. A reference design for a companion board will be documented
1796 soon, and will be compatible with open source Arduino programming tools.
1799 We are also working on the design of a hand-held ground terminal that will
1800 allow monitoring the rocket's status, collecting data during flight, and
1801 logging data after flight without the need for a notebook computer on the
1802 flight line. Particularly since it is so difficult to read most notebook
1803 screens in direct sunlight, we think this will be a great thing to have.
1806 Because all of our work is open, both the hardware designs and the software,
1807 if you have some great idea for an addition to the current Altus Metrum family,
1808 feel free to dive in and help! Or let us know what you'd like to see that
1809 we aren't already working on, and maybe we'll get excited about it too...
1814 <title>Hardware Specifications</title>
1816 <title>TeleMetrum Specifications</title>
1820 Recording altimeter for model rocketry.
1825 Supports dual deployment (can fire 2 ejection charges).
1830 70cm ham-band transceiver for telemetry downlink.
1835 Barometric pressure sensor good to 45k feet MSL.
1840 1-axis high-g accelerometer for motor characterization, capable of
1841 +/- 50g using default part.
1846 On-board, integrated GPS receiver with 5hz update rate capability.
1851 On-board 1 megabyte non-volatile memory for flight data storage.
1856 USB interface for battery charging, configuration, and data recovery.
1861 Fully integrated support for LiPo rechargeable batteries.
1866 Uses LiPo to fire e-matches, can be modiied to support
1867 optional separate pyro battery if needed.
1872 2.75 x 1 inch board designed to fit inside 29mm airframe coupler tube.
1878 <title>TeleMini Specifications</title>
1882 Recording altimeter for model rocketry.
1887 Supports dual deployment (can fire 2 ejection charges).
1892 70cm ham-band transceiver for telemetry downlink.
1897 Barometric pressure sensor good to 45k feet MSL.
1902 On-board 5 kilobyte non-volatile memory for flight data storage.
1907 RF interface for battery charging, configuration, and data recovery.
1912 Support for LiPo rechargeable batteries, using an external charger.
1917 Uses LiPo to fire e-matches, can be modiied to support
1918 optional separate pyro battery if needed.
1923 1.5 x .5 inch board designed to fit inside 18mm airframe coupler tube.
1932 TeleMetrum seems to shut off when disconnected from the
1933 computer. Make sure the battery is adequately charged. Remember the
1934 unit will pull more power than the USB port can deliver before the
1935 GPS enters "locked" mode. The battery charges best when TeleMetrum
1939 It's impossible to stop the TeleDongle when it's in "p" mode, I have
1940 to unplug the USB cable? Make sure you have tried to "escape out" of
1941 this mode. If this doesn't work the reboot procedure for the
1942 TeleDongle *is* to simply unplug it. 'cu' however will retain it's
1943 outgoing buffer IF your "escape out" ('~~') does not work.
1944 At this point using either 'ao-view' (or possibly
1945 'cutemon') instead of 'cu' will 'clear' the issue and allow renewed
1949 The amber LED (on the TeleMetrum) lights up when both
1950 battery and USB are connected. Does this mean it's charging?
1951 Yes, the yellow LED indicates the charging at the 'regular' rate.
1952 If the led is out but the unit is still plugged into a USB port,
1953 then the battery is being charged at a 'trickle' rate.
1956 There are no "dit-dah-dah-dit" sound or lights like the manual mentions?
1957 That's the "pad" mode. Weak batteries might be the problem.
1958 It is also possible that the Telemetrum is horizontal and the output
1959 is instead a "dit-dit" meaning 'idle'. For TeleMini, it's possible that
1960 it received a command packet which would have left it in "pad" mode.
1963 How do I save flight data?
1964 Live telemetry is written to file(s) whenever AltosUI is connected
1965 to the TeleDongle. The file area defaults to ~/TeleMetrum
1966 but is easily changed using the menus in AltosUI. The files that
1967 are written end in '.telem'. The after-flight
1968 data-dumped files will end in .eeprom and represent continuous data
1969 unlike the rf-linked .telem files that are subject to losses
1970 along the rf data path.
1971 See the above instructions on what and how to save the eeprom stored
1972 data after physically retrieving your altimeter. Make sure to save
1973 the on-board data after each flight; while the TeleMetrum can store
1974 multiple flights, you never know when you'll lose the altimeter...
1978 <title>Notes for Older Software</title>
1981 Before AltosUI was written, using Altus Metrum devices required
1982 some finesse with the Linux command line. There was a limited
1983 GUI tool, ao-view, which provided functionality similar to the
1984 Monitor Flight window in AltosUI, but everything else was a
1985 fairly 80's experience. This appendix includes documentation for
1986 using that software.
1990 Both Telemetrum and TeleDongle can be directly communicated
1991 with using USB ports. The first thing you should try after getting
1992 both units plugged into to your computer's usb port(s) is to run
1993 'ao-list' from a terminal-window to see what port-device-name each
1994 device has been assigned by the operating system.
1995 You will need this information to access the devices via their
1996 respective on-board firmware and data using other command line
1997 programs in the AltOS software suite.
2000 TeleMini can be communicated with through a TeleDongle device
2001 over the radio link. When first booted, TeleMini listens for a
2002 TeleDongle device and if it receives a packet, it goes into
2003 'idle' mode. Otherwise, it goes into 'pad' mode and waits to be
2004 launched. The easiest way to get it talking is to start the
2005 communication link on the TeleDongle and the power up the
2009 To access the device's firmware for configuration you need a terminal
2010 program such as you would use to talk to a modem. The software
2011 authors prefer using the program 'cu' which comes from the UUCP package
2012 on most Unix-like systems such as Linux. An example command line for
2013 cu might be 'cu -l /dev/ttyACM0', substituting the correct number
2014 indicated from running the
2015 ao-list program. Another reasonable terminal program for Linux is
2016 'cutecom'. The default 'escape'
2017 character used by CU (i.e. the character you use to
2018 issue commands to cu itself instead of sending the command as input
2019 to the connected device) is a '~'. You will need this for use in
2020 only two different ways during normal operations. First is to exit
2021 the program by sending a '~.' which is called a 'escape-disconnect'
2022 and allows you to close-out from 'cu'. The
2023 second use will be outlined later.
2026 All of the Altus Metrum devices share the concept of a two level
2027 command set in their firmware.
2028 The first layer has several single letter commands. Once
2029 you are using 'cu' (or 'cutecom') sending (typing) a '?'
2030 returns a full list of these
2031 commands. The second level are configuration sub-commands accessed
2032 using the 'c' command, for
2033 instance typing 'c?' will give you this second level of commands
2034 (all of which require the
2035 letter 'c' to access). Please note that most configuration options
2036 are stored only in Flash memory; TeleDongle doesn't provide any storage
2037 for these options and so they'll all be lost when you unplug it.
2040 Try setting these config ('c' or second level menu) values. A good
2041 place to start is by setting your call sign. By default, the boards
2042 use 'N0CALL' which is cute, but not exactly legal!
2043 Spend a few minutes getting comfortable with the units, their
2044 firmware, and 'cu' (or possibly 'cutecom').
2045 For instance, try to send
2046 (type) a 'c r 2' and verify the channel change by sending a 'c s'.
2047 Verify you can connect and disconnect from the units while in your
2048 terminal program by sending the escape-disconnect mentioned above.
2051 Note that the 'reboot' command, which is very useful on the altimeters,
2052 will likely just cause problems with the dongle. The *correct* way
2053 to reset the dongle is just to unplug and re-plug it.
2056 A fun thing to do at the launch site and something you can do while
2057 learning how to use these units is to play with the rf-link access
2058 between an altimeter and the TeleDongle. Be aware that you *must* create
2059 some physical separation between the devices, otherwise the link will
2060 not function due to signal overload in the receivers in each device.
2063 Now might be a good time to take a break and read the rest of this
2064 manual, particularly about the two "modes" that the altimeters
2065 can be placed in. TeleMetrum uses the position of the device when booting
2066 up will determine whether the unit is in "pad" or "idle" mode. TeleMini
2067 enters "idle" mode when it receives a command packet within the first 5 seconds
2068 of being powered up, otherwise it enters "pad" mode.
2071 You can access an altimeter in idle mode from the Teledongle's USB
2072 connection using the rf link
2073 by issuing a 'p' command to the TeleDongle. Practice connecting and
2074 disconnecting ('~~' while using 'cu') from the altimeter. If
2075 you cannot escape out of the "p" command, (by using a '~~' when in
2076 CU) then it is likely that your kernel has issues. Try a newer version.
2079 Using this rf link allows you to configure the altimeter, test
2080 fire e-matches and igniters from the flight line, check pyro-match
2081 continuity and so forth. You can leave the unit turned on while it
2082 is in 'idle mode' and then place the
2083 rocket vertically on the launch pad, walk away and then issue a
2084 reboot command. The altimeter will reboot and start sending data
2085 having changed to the "pad" mode. If the TeleDongle is not receiving
2086 this data, you can disconnect 'cu' from the Teledongle using the
2087 procedures mentioned above and THEN connect to the TeleDongle from
2088 inside 'ao-view'. If this doesn't work, disconnect from the
2089 TeleDongle, unplug it, and try again after plugging it back in.
2092 On TeleMetrum, the GPS will eventually find enough satellites, lock in on them,
2093 and 'ao-view' will both auditorially announce and visually indicate
2095 Now you can launch knowing that you have a good data path and
2096 good satellite lock for flight data and recovery. Remember
2097 you MUST tell ao-view to connect to the TeleDongle explicitly in
2098 order for ao-view to be able to receive data.
2101 The altimeters provide RDF (radio direction finding) tones on
2102 the pad, during descent and after landing. These can be used to
2103 locate the rocket using a directional antenna; the signal
2104 strength providing an indication of the direction from receiver to rocket.
2107 TeleMetrum also provides GPS trekking data, which can further simplify
2108 locating the rocket once it has landed. (The last good GPS data
2109 received before touch-down will be on the data screen of 'ao-view'.)
2112 Once you have recovered the rocket you can download the eeprom
2113 contents using either 'ao-dumplog' (or possibly 'ao-eeprom'), over
2114 either a USB cable or over the radio link using TeleDongle.
2115 And by following the man page for 'ao-postflight' you can create
2116 various data output reports, graphs, and even kml data to see the
2117 flight trajectory in google-earth. (Moving the viewing angle making
2118 sure to connect the yellow lines while in google-earth is the proper
2122 As for ao-view.... some things are in the menu but don't do anything
2123 very useful. The developers have stopped working on ao-view to focus
2124 on a new, cross-platform ground station program. So ao-view may or
2125 may not be updated in the future. Mostly you just use
2126 the Log and Device menus. It has a wonderful display of the incoming
2127 flight data and I am sure you will enjoy what it has to say to you
2128 once you enable the voice output!
2132 xmlns:xi="http://www.w3.org/2001/XInclude">
2133 <title>Release Notes</title>
2134 <xi:include href="release-notes-1.0.xsl" xpointer="xpointer(/article/*)"/>
2135 <xi:include href="release-notes-0.9.2.xsl" xpointer="xpointer(/article/*)"/>
2136 <xi:include href="release-notes-0.9.xsl" xpointer="xpointer(/article/*)"/>
2137 <xi:include href="release-notes-0.8.xsl" xpointer="xpointer(/article/*)"/>
2138 <xi:include href="release-notes-0.7.1.xsl" xpointer="xpointer(/article/*)"/>