Optimal control of flexible drives with load side feedback

This paper presents a new method for designing accurate motion control laws for high-speed feed drives with structural flexibility. The controller design utilizes only table (load) side feedback measurements to achieve active vibration damping and accurate tracking. Table jerk is penalized in the feedback to inject modal damping. Optimal control theory is used to tune controller for disturbance rejection and active vibration damping. In addition to good low frequency disturbance attenuation, proposed controller actively utilizes structure's anti-resonance to reject high frequency disturbances. Controller is implemented on a ball-screw drive, and its effectiveness is demonstrated in high-speed tracking experiments against industry standard P-PI control.