From afc90f63c6a0c2a511fddc97b72537e0a6f40cfd Mon Sep 17 00:00:00 2001 From: Bdale Garbee Date: Sat, 30 Jan 2021 11:48:01 -0700 Subject: [PATCH] doc: add a brief note about TeleBT appearing inert until paired --- doc/altosdroid.inc | 4 +++ doc/motortest-configuration.inc | 18 ++++++++++++ doc/motortest-installation.inc | 51 +++++++++++++++++++++++++++++++++ doc/motortest-intro.inc | 26 +++++++++++++++++ doc/motortest-operation.inc | 15 ++++++++++ 5 files changed, 114 insertions(+) create mode 100644 doc/motortest-configuration.inc create mode 100644 doc/motortest-installation.inc create mode 100644 doc/motortest-intro.inc create mode 100644 doc/motortest-operation.inc diff --git a/doc/altosdroid.inc b/doc/altosdroid.inc index dce81c3b..08e0b7e9 100644 --- a/doc/altosdroid.inc +++ b/doc/altosdroid.inc @@ -36,6 +36,10 @@ === Connecting to TeleBT over Bluetooth™ + Note that when turning TeleBT on, you may see a brief LED + flash, but there will be no "activity" indicated until you + pair with the device from AltosDroid. + Press the Android 'Menu' button or soft-key to see the configuration options available. Select the 'Connect a device' option and then the 'Scan for devices' entry diff --git a/doc/motortest-configuration.inc b/doc/motortest-configuration.inc new file mode 100644 index 00000000..173e0a38 --- /dev/null +++ b/doc/motortest-configuration.inc @@ -0,0 +1,18 @@ +== Configuration + + There is very little that must be configured to make EasyMotor work. + In fact, the default configuration from the factory is typically + sufficient without change. + + === Connecting to a Unit + + To change any EasyMotor configuration, you need to attach + a battery and a power switch, then use a micro USB cable + to connect the board to a computer running AltosUI. + + === Changing the Configuration + + All available configuration options can be set using the + "Configure Altimeter" menu selection within the AltosUI + program. + diff --git a/doc/motortest-installation.inc b/doc/motortest-installation.inc new file mode 100644 index 00000000..8a4cd77f --- /dev/null +++ b/doc/motortest-installation.inc @@ -0,0 +1,51 @@ +== Installation + + EasyMotor needs to be rigidly attached in the airframe, and the + long axis of the circuit board needs to be aligned with the axis + of flight. By default, the round beeper on the board should be + "up" towards the nose cone, and the screw terminal strips should + be "down" towards the fins and motor nozzle end of the rocket. + + === Power Switch and Battery + + In addition to the circuit board itself, EasyMotor needs + a power switch and battery to operate. Unlike most other + Altus Metrum products, EasyMotor does not work with + single-cell LiPo batteries. That's because commonly + available inexpensive pressure sensors need 5V, which is + more than a single-cell LiPo provides. Any battery that + provides from 6.5 to about 15 volts should work. Good + choices are the common 9V alkaline battery, or the very + small and light A23 12V alkaline batteries. + + Because he often mounts EasyMotor to the motor's forward + bulkhead instead of to the airframe itself, Bdale often + uses a length of "shooter wire" from an e-match or used + motor igniter as a power switch, routing the wire out of + the typical fin can vent hole and using "twist and tape" + to power up the board. Whatever works! + + === Pressure Sensor + + The primary motivation for designing EasyMotor was to have + a reliable way of recording motor chamber pressure during + flight. To that end, EasyMotor supports attachment of a + low-cost analog pressure sensor. The board provides 5V + to power the sensor, and an input for measuring and + logging the output voltage from the sensor. + + The kind of sensor EasyMotor is designed to work with + takes 5V in and has a linear analog output that ranges + from 0.5V at 0 to 4.5V at the maximum pressure supported + by the sensor. Very inexpensive sensors that have a + "1/8 NPT" threaded input, a "Buick-style" 3-pin connector, + and typically ship with a short cable and mating + connector, are readily available on eBay and AliExpress. + + To log in-flight chamber pressure, a typical approach + might be to drill a 1/8" sampling hole all the way + through the center of the motor's forward closure, then + drill and tap partially through the closure with a "1/8 + NPT" pipe tap. Fill the touch hole with grease, screw in + the pressure sensor, and attach the sensor leads to + EasyMotor. diff --git a/doc/motortest-intro.inc b/doc/motortest-intro.inc new file mode 100644 index 00000000..9a8ea6de --- /dev/null +++ b/doc/motortest-intro.inc @@ -0,0 +1,26 @@ +== Introduction and Overview + +Welcome to the Altus Metrum community! Our circuits and software reflect +our passion for both hobby rocketry and Free Software. We hope their +capabilities and performance will delight you in every way, but by +releasing all of our hardware and software designs under open licenses, +we also hope to empower you to take as active a role in our collective +future as you wish! + +Thank you for your interest in EasyMotor, an in-flight motor data collection +board for hobby rockets. EasyMotor is a small circuit board that is meant +to log motor chamber pressure and rocket acceleration during flight. With +this data it's possible to determine whether a research motor is performing +as expected. With additional information about masses and airframe drag, +it is even possible to closely estimate complete motor performance. + +With EasyMotor, the dilemma of "do I burn this on a test stand to learn more +about how it actually works, or do I go fly it" is no more! You can fly your +motor and get real performance data about it too! + +Because documentation is just as prone as software to contain "bugs", and +can always be improved... If you have questions that aren't answered in this +manual, or just need a little help figuring things out, we strongly suggest +joining the Altus Metrum user email list, which you can do by visiting +https://lists.gag.com/mailman/listinfo/altusmetrum. + diff --git a/doc/motortest-operation.inc b/doc/motortest-operation.inc new file mode 100644 index 00000000..da0220f2 --- /dev/null +++ b/doc/motortest-operation.inc @@ -0,0 +1,15 @@ +== Operation + + Operating an EasyMotor board is pretty easy. Turn the power on + before launch, typically during the usual pre-flight electronics + checklist after the rocket is installed on a launch rail. + + The board will beep out a Morse code "P" every few seconds + indicating that it's in pad mode and ready to detect launch. + Once launch is detected, the board logs pressure and acceleration + data 100 times per second throughout the flight. + + After flight, AltosUI can be used to download the flight data, + then export it to a comma separated values (CSV) file. Such a + file can easily be loaded into a spreadsheet for analysis. + -- 2.30.2