Stimulant

Hardware agnostic flight software for high power rockets.

Want to contribute? Start here.

NOTE: At this time we are only accepting contributions from HLA members for issues with the beginner label.

Instructions for use

Goals:

Feature	Status
launch detection	✔️
altitude monitoring	✔️
location monitoring	✔️
attitude determination
velocity determination
postition determination (non-GPS)
live telemetry transmission	✔️
apogee detection	✔️
drogue chute deployment
main chute deployment
data acquisition (SD card)	✔️

Software Architecture:

Flow Chart

Hardware:

This software can support any configuration of hardware with exactly one of each of the following types:

• Microcontroller
• Inertial Measurement Unit
• GPS
• Radio transceiver

The following hardware is currently supported:

• Teensy 4.1
• RaspberryPi Pico
• Adafruit BMP388/BMP390 Barometric Altimeter
• GY521 IMU (MPU 6050)
• LSM6DSOX IMU
• Adafruit Ultimate GPS
• Xbee-PRO S3B

Best Practices For Making Changes:

• make sure your code compiles to verify your changes
• comment your code
• multiple small functions are better than one big one. Remember, each function should only do one thing
• break out groups of functions into their own files. Long files are difficult to read. Ideally main.ino would only have void setup() and void loop()

Instructions for use:

1. Connect all sensors and power source.
2. If using pyros, verify that the the power supply is OFF and then attach them.
3. Integrate the flight computer with rocket (try to keep IMU aligned with axis of rotation)
4. Place rocket on launch rail.
5. Power on flight computer
   • VERIFY: Do NOT power on flight computer until EITHER of the following have been verified:
     • The rocket is upright on the launch pad.
     • The Pyros have been disconnected. (Necessary only if rocket is not on the launch pad)
   • CAUTION: Once powered on, any sudden movements may trigger launch detection
6. Wait at least 5 minutes between powering on and launching to allow for proper sensor calibration
7. Launch!

Note: Due to the use of the micros() function, the rocket MUST be launched within 60 minutes of powering on. If you do not launch within that period you must restart the flight computer by turning it off and then on again.