Adaptive impedance control of piezoelectric microgripper

Abstract

Delicate interaction control is a crucial issue for automated microsystems dedicated to micromanipulation of microobjects. This chapter presents a framework of digital sliding mode generalized impedance control with adaptive switching gain to regulating both the position and contact force of a piezoelectric-bimorph microgripper for micromanipulation and microassembly applications. Based on a second-order dynamicsmodel, its implementation does not require a state observer and a hysteresis/ creep model. The stability of the control system is proved in theory, which ensures the tracking performance in the presence of model uncertainties and disturbances. The effectiveness of the scheme is validated by experimental investigations on the grasp operation of a microgear.