This video is more than you ever wanted about PID tuning for a multirotor. A brief overview of our control scheme is given, followed by a demonstration of tuning a quadcopter on a string and then in the air. Finally, for those interested, a set of simulations is presented to try and give an intuition about what the terms do to both attitude and rate control.
The consequence of having various parameters too high is demonstrated in flight to help users identify tuning problems.
To simulate the code yourself, if you have Matlab and the Control Toolbox, get it from http://wiki.openpilot.org/display/Doc/Control+code+simulation. I also want to make it clear that the magnitude of those values are in no way generalizable between simulations and between aircrafts – just the trends are. There are also plenty of parameters I didn’t systematically vary (such as reaction speed of ESC).
Kenz also suggested a clearer way to show the figures towards the end with the interaction of attitude and rate Kp:
Note: Axis lock is currently not in the packaged version of our software. Should be out shortly though.