Improvement of vibration suppression performance of galvano mirror using piezoelectric element

This paper presents a vibration suppression approach for galvano mirrors in laser positioning systems. The systems require the fast and high-precision positioning of the mirror and should maintain the flatness of the mirror after positioning to ensure the control performance. However, resonant vibrations of the mirror, which are excited by the moment force during positioning, lead to residual vibrations after positioning, deteriorating the flatness of the mirror and laser manufacturing accuracy. In this paper, therefore, a vibration suppression approach is proposed by mounting a piezoelectric element on the mirror, where a multi-function of the piezoelectric element as an actuator and a sensor are applied to design the vibration suppression controller. The applicability of the proposed approach to industrial galvano scanners has been verified by performing experiments using a prototype.