슬라이딩 모드 관측기를 이용한 피에조구동기 미세제어

Abstract

In this thesis, we propose tracking control technique for piezoelectric actuator based on a design of a controller with sliding mode obsever. Piezoelectric actuator provides us with displacement as output given input voltage. However, we need to get more information such as velocity of piezoelectric actuator and hysteresis on tracking problem. Hysteresis, especially, is main factor to make the system of piezoelectric actuator the nonlinear system. Therefore, sliding mode observer is proposed to estimate full state which is displacement, position, and hysteresis using only measurement output displacement even model parameter uncertainty. When only the output displacement is feasible in feedback, the observer estimates the full state in finite time. The controller is designed for reference tracking control using estimated full state by sliding mode observer. Through simulation, it is found that the tracking error is improved using the proposed method.