Design, modeling, and simulation of a 2-DOF microgripper for grasping and rotating of optical fibers

Aiming at the micro-assembly of optical fibers, a novel 2-DOF microgripper with an asymmetric structure is proposed. Compared with conventional microgrippers, the proposed one can achieve multi-finger operations of grasping and rotating. In this paper the design of the whole device is presented. And the kinetostatic and dynamic modeling of the gripper are established using the pseudo-rigid-body model method. In order to validate the performance and optimize the design of the gripper, finite element analysis (FEA) is conducted. The simulation results indicate that: 1) the maximum stress in the microgripper is much smaller than the critical stress for fatigue; 2) with the proper amplification ratio and the stroke of the piezoelectric actuator (PZT), the grasping displacement of the designed gripper can reach 180 μm, and the optical fiber with 100 μm in diameter can be rotated by a maximum angle of 90°, which has great potential in applications.