This paper designs a ground motion compensation servo system based on two-dimensional pointing mirror. The servo
system is mainly composed of digital control unit, analog driving unit and driving motor. Besides, the control algorithm
and strategy of driving motor would be given, and based on the control strategy, a closed-loop controller which consists
of current loop, velocity loop and position loop is designed and simulated. Especially, the speed loop adopts pseudo
differential feed-forward (PDFF) controller to avoid extensive overshoot. Finally, the experiment results show that the
designed servo system has fast response and small overshoot.