[KenWittlief]

the time it takes is one fourtieth of a second for the feed back loop to see that 'something' is trying to push the robot sideways, when its not suppose to be going sideways, and the SW corrects the power to the motor to force it to do what the driver wants.

This works to stablize castors, it also works if you hit a ball, if a bot hits you, you encounter a change in resistance (like driving on carpet or on the smooth surface)

and it worked last year going up the ramp at an angle.

The PID loop doesnt care whats trying to push the bot off course, it senses the slightest change in yaw rate, and applies an immediate correction.

We used it last year - the bot steered like it was a large servo.