I have done auto-tune in the past, but I'm currently having problems which I can't seem to resolve.
My setup includes a 3DR Pixhawk running ArduCopter firmware 3.3.2 with the default values for the PID.
I've setup Channel 5 to get into Alt-Hold, and channel 7 is set to start auto-tune. Also re-did the radio calibration several times.
When I fly and follow the procedure, auto-tune doesn't seem to do anything.
To verify that all is set correctly, I connect the Pixhawk to the mission planner on the ground, and do the following to simulate the procedure:
2. Raise throttle to avoid Disarm
3. Enter Alt-Hold
4. Switch to auto-tune
The display does show the auto-tune as starting, so it doesn't seem to be a configuration issue, but still, when in the air, nothing seems to be happening.
I would appreciate any help in resolving this.