From: Bdale Garbee Date: Thu, 25 Aug 2011 04:27:35 +0000 (-0600) Subject: more doc tweaking X-Git-Tag: 1.0~20 X-Git-Url: https://git.gag.com/?p=fw%2Faltos;a=commitdiff_plain;h=d4e1aa92b6ce2f3e4c51029595d1d44a7f2f14a0 more doc tweaking --- diff --git a/doc/altusmetrum.xsl b/doc/altusmetrum.xsl index 0fe0dc79..af892e0f 100644 --- a/doc/altusmetrum.xsl +++ b/doc/altusmetrum.xsl @@ -231,57 +231,56 @@ NAR #88757, TRA #12200 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 default 1/4 - wave UHF wire antenna attached to the center of the nose-cone end of - the board is about 7 inches long, and wiring for a power switch and + 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. Given all this, an ideal "simple" avionics + fin can end of the board, meaning an ideal "simple" avionics bay for TeleMetrum should have at least 10 inches of interior length. 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! The default 1/4 - wave UHF wire antenna attached to the center of the nose-cone end of + 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 - fin can end of the board. Given all this, an ideal "simple" avionics + other end of the board, meaning an ideal "simple" avionics bay for TeleMini should have at least 9 inches of interior length. - A typical TeleMetrum or TeleMini installation using the on-board devices and - default wire UHF antenna involves attaching only a suitable - Lithium Polymer battery, a single pole switch for power on/off, and - two pairs of wires connecting e-matches for the apogee and main ejection - charges. + 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. 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 up to 15V. + 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. Ejection charges are wired directly to the screw terminal block - at the aft end of the altimeter. This is very similar to what - most other altimeter vendors provide and so may be the most - familiar option. You'll need a very small straight blade - screwdriver to connect and disconnect the board in this case, - such as you might find in a jeweler's screwdriver set. + 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. 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 the switch. + directly to the board and can be connected directly to a switch. For most air-frames, the integrated antennas are more than - adequate However, if you are installing in a carbon-fiber - electronics bay which is opaque to RF signals, you may need to + 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 @@ -303,7 +302,8 @@ NAR #88757, TRA #12200 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. For TeleMini, "idle" mode is selected when the + 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. @@ -311,8 +311,8 @@ NAR #88757, TRA #12200 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 tests, and decides which - mode to enter next. + the altimeter completes initialization and self test, and decides + which mode to enter next. In flight or "pad" mode, the altimeter engages the flight @@ -330,44 +330,43 @@ NAR #88757, TRA #12200 flights, do what makes sense. - In idle mode, you will hear an audible "di-dit" or see two short flashes ("I" for idle), and - the normal flight state machine is disengaged, thus - no ejection charges will fire. The altimeters also listen on the RF - link when in idle mode for packet mode requests sent from TeleDongle. - Commands can be issued to a TeleMetrum in idle mode over either - USB or the RF link equivalently. TeleMini uses only the RF link. + 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 on the RF 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 RF link equivalently. TeleMini only has the RF 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. - One "neat trick" of particular value when the altimeter 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, use a TeleDongle to open - a packet connection, and issue a 'reset' command which will 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! + 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 RF 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!
GPS - TeleMetrum includes a complete GPS receiver. See a later section for - a brief explanation of how GPS works that will help you understand - the information in the telemetry stream. The bottom line is that - the TeleMetrum GPS receiver needs to lock onto at least four - satellites to obtain a solid 3 dimensional position fix and know - what time it is! + TeleMetrum 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. - TeleMetrum provides backup power to the GPS chip any time a Li-Po + 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 "cold start" - for the GPS receiver. In typical operations, powering up TeleMetrum + 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 @@ -383,29 +382,19 @@ NAR #88757, TRA #12200 An important aspect of preparing a rocket using electronic deployment for flight is ground testing the recovery system. Thanks to the bi-directional RF link central to the Altus Metrum system, - this can be accomplished in a TeleMetrum- or TeleMini- equipped rocket without as - much work as you may be accustomed to with other systems. It can - even be fun! + 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! Just prep the rocket for flight, then power up the altimeter in "idle" mode (placing air-frame horizontal for TeleMetrum or - starting the RF packet connection for TeleMini). This will cause the - firmware to go into "idle" mode, in which the normal flight + 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. Then, establish an RF packet connection from - a TeleDongle-equipped computer using the P command from a safe - distance. You can now command the altimeter to fire the apogee - or main charges to complete your testing. - - - 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'. + 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.
@@ -2333,6 +2322,15 @@ NAR #88757, TRA #12200 inside 'ao-view'. If this doesn't work, disconnect from the TeleDongle, unplug it, and try again after plugging it back in. + + 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'. + On TeleMetrum, the GPS will eventually find enough satellites, lock in on them, and 'ao-view' will both auditorily announce and visually indicate