<revhistory>
<revision>
<revnumber>1.0</revnumber>
- <date>10 August 2011</date>
+ <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.
+ telemetry format change, meaning both ends of a link
+ (TeleMetrum/TeleMini and TeleDongle) must be updated or
+ communications will fail.
</revremark>
</revision>
<revision>
<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 has turned into the Getting Started chapter in this
- book. Bob was one of our first customers for a production
- TeleMetrum, and the enthusiasm that led to his contribution of
- this section is immensely gratifying and highly appreciated!
+ Kit" which formed the basis of the original Getting Started chapter
+ in this manual. Bob was one of our first customers for a production
+ TeleMetrum, and his continued enthusiasm and contributions
+ are immensely gratifying and highly appreciated!
</para>
<para>
- And thanks to Anthony (AJ) Towns for contributing the
- AltosUI graphing and site map code and documentation. Free
- software means that our customers and friends can become our
+ And thanks to Anthony (AJ) Towns for major contributions including
+ the AltosUI graphing and site map code and associated documentation.
+ Free software means that our customers and friends can become our
collaborators, and we certainly appreciate this level of
- contribution.
+ contribution!
</para>
<para>
Have fun using these products, and we hope to meet all of you
<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.
+ 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
+ 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
ugly bugs in some earlier versions.
</para>
<para>
- Next you should obtain and install the AltOS utilities. These include
+ 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 Debian
- Linux, Microsoft Windows, and recent MacOSX versions. Full source code
- and build instructions for some other Linux variants are also available.
+ 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>
<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, like all electronic
+ will deliver impressive results. However, as with all electronic
devices, there are some precautions you must take.
</para>
<para>
</para>
<para>
In flight or "pad" mode, the altimeter engages the flight
- state machine, goes into transmit-only mode on the RF link
- sending telemetry, and waits for launch to be detected.
+ 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.
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
+ 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 RF link equivalently. TeleMini only has the RF link.
+ 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.
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
+ 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
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 packet command mode in 'idle' mode, so
+ make sure you have TeleMetrum lying horizontally when you turn
+ it on. Otherwise, TeleMetrum will start in 'pad' mode ready for
+ flight and will not be listening for command packets from TeleDongle.
+ </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>
+ When packet command mode is enabled, you can monitor the link
+ by watching the lights on the
+ devices. The red LED will flash each time they
+ transmit a packet while the green LED will light up
+ on TeleDongle while 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 RF link central to the Altus Metrum system,
+ 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!
link.
</para>
<para>
- By design, the altimeter firmware listens for an RF connection when
+ By design, the altimeter firmware listens for the radio link when
it's in "idle mode", which
- allows us to use the RF link to configure the rocket, do things like
+ 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 and out over
- the RF link in case the rocket crashes and we aren't able to extract
+ 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 because they're just too
- inefficient. The GFSK modulation we use is just FSK with the
+ 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 good reception, and calculations
- suggest we should be good to well over 40k feet AGL with a 5-element yagi on
- the ground. We hope to fly boards to higher altitudes soon, and would
- of course appreciate customer feedback on performance in higher
- altitude flights!
+ 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. Through the use of a Kalman filter, there is no need
- to set a "mach delay" . The few configurable parameters can
- all be set using a simple terminal program over the USB port
- or RF link via TeleDongle.
+ 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 Frequencies</title>
<para>
The Altus Metrum boards support frequencies in the 70cm
band. By default, the configuration interface provides a
- list of 10 common frequencies -- 100kHz channels starting at
- 434.550MHz. However, you can configure the firmware to use
+ list of 10 common 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 who will use each
frequency and when to avoid interference. And of course, both
<para>
In the unlikely event an accel cal that goes badly, it is possible
that TeleMetrum may always come up in 'pad mode' and as such not be
- listening to either the USB or radio interfaces. If that happens,
+ 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
</listitem>
<listitem>
Confirm that the TeleMini board seems to have updated OK, which you
- can do by configuring it over the RF link through the TeleDongle, or
+ 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>
</para>
</section>
</section>
- <section>
- <title>Packet Command Mode</title>
- <subtitle>Controlling An Altimeter Over The Radio Link</subtitle>
- <para>
- One of the unique features of the Altus Metrum environment is
- the ability to create a two way command link between TeleDongle
- and an altimeter using the digital radio transceivers built into
- each device. This allows you to interact with the altimeter from
- afar, as if it were directly connected to the computer.
- </para>
- <para>
- Any operation which can be performed with TeleMetrum can
- either be done with TeleMetrum directly connected to the
- computer via the USB cable, or through the packet
- link. TeleMini doesn't provide a USB connector and so it can
- only be controlled through the packet link. Select the
- appropriate TeleDongle device when the list of devices is
- presented and AltosUI will use packet command mode.
- </para>
- <para>
- One oddity in the current interface is how AltosUI selects the
- frequency for packet mode communications. Instead of providing
- an interface to specifically configure the frequency, it uses
- whatever frequency was most recently selected for the target
- TeleDongle device in Monitor Flight mode. If you haven't ever
- used that mode with the TeleDongle in question, select the
- Monitor Flight button from the top level UI, pick the
- appropriate TeleDongle device. Once the flight monitoring
- window is open, select the desired frequency and then close it
- down again. All Packet Command Mode operations 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>
- Packet command mode uses the same RF frequencies as telemetry
- mode. Configure the desired TeleDongle frequency using the
- flight monitor window frequency selector and then close that
- window before performing the desired operation.
- </para>
- <para>
- TeleMetrum only enables packet command mode in 'idle' mode, so
- make sure you have TeleMetrum lying horizontally when you turn
- it on. Otherwise, TeleMetrum will start in 'pad' mode ready for
- flight and will not be listening for command packets from TeleDongle.
- </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>
- When packet command mode is enabled, you can monitor the link
- by watching the lights on the
- devices. The red LED will flash each time they
- transmit a packet while the green LED will light up
- on TeleDongle while it is waiting to receive a packet from
- the altimeter.
- </para>
- </section>
<section>
<title>Save Flight Data</title>
<para>
for Linux which can perform most of the same tasks.
</para>
<para>
- After the flight, you can use the RF link to extract the more detailed data
+ 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
<title>Data Analysis</title>
<para>
Our software makes it easy to log the data from each flight, both the
- telemetry received over the RF link during the flight itself, and the more
+ 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,
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 RF-linked .telem files that are subject to losses
+ 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
</para>
<para>
A fun thing to do at the launch site and something you can do while
- learning how to use these units is to play with the RF-link access
+ 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>
You can access an altimeter in idle mode from the TeleDongle's USB
- connection using the RF link
+ 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 RF link allows you to configure the altimeter, test
+ 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
projects / fw / altos / blobdiff