Jordi has finished the first pass on the code for the new BlimpDuino boards
. It's best to consider this pre-alpha and not fully functional, but if you want to see how we read IR and ultrasonic sensors, read RC channels, drive a servo and twin motors and use PID loops to hold altitude and navigate, you'll find it instructive. It's practically a primer in Arduino robotics.
Of particular note are the PID control loops, which are a big step up from the basic P (proportional only) loops we were using before. There's also some new code to check the battery voltage and shut down if gets too low, protecting the LiPo.
Overall, this code is designed to be efficient and to conserve power. We run the Atmega using its internal 8Mhz clock rather than the 20mhz external crystal we use with ArduPilot, and we keep ultrasonic pings to a minimum.
The main thing we need to add now is my RC-mode code
The code is here
Stay tuned for proper beta code in a week after Jordi's been able to test it in the air.