Design and Characteristics of a Novel Compliant Symmetric Microgripper Mechanism

A novel high natural frequency microgripper with symmetric compliance structure is reported in this paper, which is actuated by a piezoelectric actuator (PZT). Two lever mechanisms are utilized to amplify the output displacement of the PZT to achieve a large jaw desired output displacement. The symmetric lever mechanism and the jaws are designed separately and then the microgripper is constructed by assembling the two parts together. So different kinds of objects can be manipulated through designing different jaws, which broaden the application of the microgripper. The analytical model has been established based on pseudo-rigid-body (PRB) modeling method and matrix-based compliance modeling (MCM) method. According to the established model, the performance of the microgripper including amplification ratio, input stiffness and natural frequency are analyzed. Finite element analysis (FEA) is carried out to investigate the performance and validate the theoretical models for further optimum design of the microgripper.