Robust 2-Degrees-Of-Freedom Vibration Suppression Controller Design Based on Simultaneous Optimization between Feedforward and Feedback Compensators

Abstract

This paper presents a novel simultaneous optimization between feedforward (FF) and feedback (FB) compensators in 2-degree-of-freedom (2-DOF) positioning systems for robust vibration suppression control against frequency perturbations of mechanical vibration modes. The authors have already proposed a coordinate design between the FF and the FB compensators of the 2-DOF controller to improve the robust properties in the positioning. In the conventional approach, however, residual vibrations due to the frequency perturbations still remained after the settling because the conventional coordinate design was a quasi-optimization of the 2-DOF controller. In this study, therefore, a simultaneous optimization is adopted to suppress the residual vibration. The effectiveness of the proposed controller design has been verified by numerical simulations and experiments using a prototype of a galvano scanner.