[DonRotolo]

Just to be clear, the Gyro used in FRC gives you the Rate of Turning, in degrees per second. So if you want to keep your robot from turning, just maintain the gyro value at zero - if it turns at 2 degrees per second for 3 seconds, then turn it back the same 6 degrees.

Just be aware that a gyro has some "drift"; that is, it reports small turn rates even while not moving. This can be mostly managed by adjusting for temperature (there is a temperature sensor on-board) and some empirical measurements, not perfectly but well enough for a 2 minute match. Not to mention your driver can 'adjust' the actual position a little if/when necessary, leaving the majority of the work to the automated system.