I just finished another prototype for my autopilot module. The biggest changes are:
- SMD components!
- Runs on 3.3V: more sensor stability.
- Possibility to use an external crystal instead of the internal oscillator.
The software is finished for about 80-90%. For the moment it looks promising. At only 8MHz (that only 2MIPS!), the module does the following, 50 times per second:
- Decode (and glitch filter) PPM pulse train from RC-receiver.
- Send PWM signals to the servos.
- Sampling of the sensor values and filtering them with a 4th order runge-kutta filter.
- Decode GPS input at 2Hz.
- Kalman filtering pitch and roll.
- A simple PID algorithm for stabilization.
Looks nearly finished… however, testing in a real MAV and finetuning everything will take a lot of time!