started this morning working on the PID controller. Many thanks to the guys at

http://www.thomasteisberg.com/quadcopter/index.html#control

From whom I stole some useful code.

It's not working great, as you will see from the video. I suspect that my pitch and roll measurements aren't as snappy as they used to be, so the controller is always using data that's too old.

Check it out.

Oscillation in action

Enjoy!