Having seen both these devices:
Knightcrawler: Turns by adjusting the speed of the motors (ie, tank drive on 2 wheels) through the handlebar throttles.
Craigway: It doesn't, yet. The turning you see in the video is simply caused by the rider shifting the balance of his weight. And no, the turning in the final product should have no affect on the gyro at all. That's more a programming issue than anything else, but if you think about it, the gyro is only 1-axis. When the device turns, it is simply rotating that single axis that the gyro can read, so it should not be affected at all.
