Yes, it is impressive that he got it going with PID controllers plus whatever else is in the controller firmware. This sort of inverted pendulum type system wo

Yes, it is impressive that he got it going with PID controllers plus whatever else is in the controller firmware. This sort of inverted pendulum type system would typically require at least 1/s^2 control. It also has the additional complexity of gyroscopic torques, center of thrust not through center of gravity and servo control lag. This is similar to controlling a rocket, something the Germans took a long time to perfect with the WW2 V2 missile.