[billbo911]

Originally Posted by Andrew Schreiber

Working on similar. One issue I've been running into is the transition between turning and not turning. On the comp bot (H drive) this year we just have the driver toggle between heading lock mode and not. But that's not really a great solution long term. Any suggestions?

Absolutely.

How I got the Vex Kiwi to transition between Gyro stabilization (Heading Lock) and open loop control is really simple. I just sampled the "Rotation" input from the joystick, and used a "window" to detect when rotation was being commanded. Any rotation input outside the window caused the gyro input to be ignored and allowed the rotation command to control the rotation of the robot. As soon as the rotation input entered the window again, the current gyro direction value was set to zero and then the gyro direction was used to control the rotation once again.

One key to making this transition smooth is to set the "window" to closely match the range of the "Rotation" command deadband that doesn't quite make a change in the robot's rotation.
IIRC, that range for the Vex was from >122 to <130.