A compensation function constituting device calculates a correlation coefficient based on a moving distance required for reversing a moving direction of a movable unit and a sliding resistance acting on the movable unit, and a compensation amount output device calculates a moving distance on a position command value required until the movable unit starts to move according to the correlation coefficient and a feedback torque when the moving direction is reversed and increases a torque compensation amount in accordance with the moving distance after reversing the moving direction until the moving distance after the moving direction is reversed reaches the moving distance required until the movement is started.