Resonance Compensation Research of Tip-Tilt Mirror's 2-Dof Tracking-Disturbance Rejection Problem

This paper discusses about the target tracking problem with high-frequencies disturbance rejection demand in tip-tilt mirrors, where the mechanical vibration disturbances always exist near the system’s resonance. Resonance’s influence to system’s tracking performance is analyzed. And a modified two degrees of freedom (2-DOF) control scheme is proposed. Utilizing the decoupling capacity, the feedback control without resonance compensation is designed to attenuate system resonance’s neighboring disturbances, and feedforward controller is added to make up for the sacrifice in tracking performance. As the tracking performances are difficult to be fuses and judged, the parameters’ tuning problem are skillfully translated into proportion optimization problem with genetic algorithm. By this method, the controller can be finely designed and tuned to match particular systems and meet the performance demands. A series of simulations and experiments illustrate the effectiveness of this new 2-DOF control scheme