Application of self-sensing technique for position control considering vibration suppression in piezo-driven stage

This paper presents a position control approach considering vibration suppression using self-sensing techniques in piezoelectric actuators. In order to achieve the high precision positioning using piezoelectric actuators, mechanical vibrations as well as nonlinear properties should be compensated. In this paper, a robust vibration suppression control system against resonant frequency variations is designed, where a minor loop aided by a self-sensing technique is added on the position control system. In the minor loop design, the reduction of sensitivity characteristic at around the vibration frequencies is considered to suppress the residual vibration for the reference and disturbance. Major loop for augmented plant including self-sensing minor loop, on the other hand, is designed by considering system stability and servo characteristic. The proposed approach has been evaluated by experiments using a piezo-driven stage.