The arm plays with a laudable amount of subtlety. It pays attention to the drummer, switching between the ride cymbal and the floor tom depending on which other parts of the drum the musician is using. It changes tempo in response to the drummer speeding up or slowing down.
Built-in accelerometers and motors help keep the robo-arm in position and on beat. The builders programmed the arm using motion-capture technology to give it human-like movements.