Development of a high speed and precision wire clamp with both position and force regulations

This paper presents the mechanism and robust control of a monolithic wire clamp to achieve fast and precision operations for strong and robust micro device packaging. The wire clamp is piezoelectrically actuated and a two-stage flexure-based amplification was designed to obtain large and parallel jaw displacements. The grasping forces of the wire clamp were evaluated based on finite element analysis (FEA), and the force measurement was presented. The wire clamp was manufactured using wire EDM technique and the position and force transfer functions were obtained based on the frequency response approach. The position/force switching control strategy was employed to regulate the motion position and grasping force, and the position/force switching controller composed of a PID controller for position control and a sliding model controller (SMC) for force control was designed. Experimental tests were carried out to investigate the performance of wire clamp with the position/force switching controller during the grasping and releasing operations. The results show that the wire clamp exhibits good performance and demonstrate that high speed and precision grasping operations can be realized through the developed wire clamp and the control strategy.