I have been thinking about building a radio based telemetry setup for a while and I finally decided to take the plunge with my son. Previous posts have provided a lot of good insight, but I havent seen any exactly like what I am considering. I was inspired last weekend from watching a few student groups struggle to get telemetry from a laptop station (in the dirt), while launching big rockets for the NASA challenge.
The initial plan would be to have a package on the rocket tracking all significant activity using an Arduino, GPS, barometer, accelerometer/gyro (MPU6050), logging everything to memory and SD, and transmitting via radio to a hand-held Arduino base station box. The first version wouldnt be used for dual deploy, but as I got more confident in the system it could be used for dual deploy charges and other sensing (e.g., mag switches to detect separation).
The handheld unit would also utilize an Arduino, TFT display (or something faster), a serial radio, SD card, GPS, and Im considering speaker/MP3 player output for voice notification (similar to Kate). An Arduino might not have the power for the ground-based handheld, so I might switch to a Raspberry Pi, but Ill take a run at using a fast Arduino first.
At a minimum, I want to capture all the basics: launch detect, periodic altitude, speed intervals, top speed, top gs, apogee, deploy detect, descent rate, GPS location, distance, etc. The idea would be to capture locally on the rocket at a high resolution and send packets down at intervals during launch (e.g., every x thousand feet) and then on descent transmit more data, so the hand-held has everything before it lands. The local Arduino on the rocket would log to memory and then to SD card. The hand held Arduino would display critical information on a screen and log radio traffic to the SD card. The handheld could also graph the flight data, provide simple map/direction tracking, etc.
I have a lot of experience with Arduinos, various screens/output, SD cards, etc. I have also bench tested a few different 433Mhz radios with serial transmission. Ive also put a barometer, MPU6050, and GPS through code unit testing, but I havent started putting things together yet.
I dont need the package to be super tiny. I dont plan on flying it on anything less than 4, but it would be nice to keep things as small and light as possible.
Any advice on the following would be appreciated:
1) GPS - I recall that GPS units are either fast or high, but not allowed to be both. Any recommendations on devices, antennas, or placement? I have had failures on space balloons with GPS units turning over. Any thoughts about using two GPS devices - one up one down for descent?
2) Radios - I have my Amateur Radio license, but good (high wattage) options are still limited. Small TTY serial radios in the 2M or 70cm bands around 2W would be ideal.
3) Sample code - if anyone already has good sample code that integrates the logic across the devices (e.g., compare accelerometer data to barometer for apogee detect).
Im happy to open source and share the learnings when I have something complete. Given how cheap the components have become, this should be a relatively inexpensive way to have streaming flight data.
Thanks,
Mike
The initial plan would be to have a package on the rocket tracking all significant activity using an Arduino, GPS, barometer, accelerometer/gyro (MPU6050), logging everything to memory and SD, and transmitting via radio to a hand-held Arduino base station box. The first version wouldnt be used for dual deploy, but as I got more confident in the system it could be used for dual deploy charges and other sensing (e.g., mag switches to detect separation).
The handheld unit would also utilize an Arduino, TFT display (or something faster), a serial radio, SD card, GPS, and Im considering speaker/MP3 player output for voice notification (similar to Kate). An Arduino might not have the power for the ground-based handheld, so I might switch to a Raspberry Pi, but Ill take a run at using a fast Arduino first.
At a minimum, I want to capture all the basics: launch detect, periodic altitude, speed intervals, top speed, top gs, apogee, deploy detect, descent rate, GPS location, distance, etc. The idea would be to capture locally on the rocket at a high resolution and send packets down at intervals during launch (e.g., every x thousand feet) and then on descent transmit more data, so the hand-held has everything before it lands. The local Arduino on the rocket would log to memory and then to SD card. The hand held Arduino would display critical information on a screen and log radio traffic to the SD card. The handheld could also graph the flight data, provide simple map/direction tracking, etc.
I have a lot of experience with Arduinos, various screens/output, SD cards, etc. I have also bench tested a few different 433Mhz radios with serial transmission. Ive also put a barometer, MPU6050, and GPS through code unit testing, but I havent started putting things together yet.
I dont need the package to be super tiny. I dont plan on flying it on anything less than 4, but it would be nice to keep things as small and light as possible.
Any advice on the following would be appreciated:
1) GPS - I recall that GPS units are either fast or high, but not allowed to be both. Any recommendations on devices, antennas, or placement? I have had failures on space balloons with GPS units turning over. Any thoughts about using two GPS devices - one up one down for descent?
2) Radios - I have my Amateur Radio license, but good (high wattage) options are still limited. Small TTY serial radios in the 2M or 70cm bands around 2W would be ideal.
3) Sample code - if anyone already has good sample code that integrates the logic across the devices (e.g., compare accelerometer data to barometer for apogee detect).
Im happy to open source and share the learnings when I have something complete. Given how cheap the components have become, this should be a relatively inexpensive way to have streaming flight data.
Thanks,
Mike