According to iRobot, the “hamster controls the robot by running in the ball in whatever direction he/she likes — ball is supported on three rollers and an optical sensor measures which way and how fast the ball is spinning.” Video after the break.

The sensor data is fed to a microprocessor which drives the Create in the same way. Remember, this is exactly what the Create is designed to do: whatever you want.

[via BotJunkie]