Robust vibration suppression control for resonant frequency variations in dual-stage actuator-driven load devices

This paper presents a controller design approach considering robustness against resonant frequency variations in load devices. In the target load device, a pneumatic actuator and a voice coil motor are combined as a dual-stage actuator to expand the servo bandwidth. In order to provide the precise control performance, not only interference between actuators but also resonant vibrations should be compensated. In addition, the controller should be designed to achieve the robust frequency variations. In this paper, PQ method is applied to compensate for the basis of H_∞ control framework. The proposed approach has been verified by experiments using a prototype of load device.