Design of a New Compliant Piezoelectric Microgripper with Parasitic Motion Self-Compensation

This paper presents the design and optimization of a novel piezoelectric-driven symmetrical microgripper with parasitic motion self-compensation. For the first time, the microgripper achieve parasitic motion self-compensation for the gripping ends of the four-bar parallelogram mechanisms without using an extra actuator, which facilitates high precision gripping/releasing tasks. Its uniqueness is that the self-compensatory mechanism is integrated with the output end of the piezoelectric actuator to synchronously move the non-gripping ends of the four-bar parallelogram mechanisms to compensate for its parasitic motion in real time. The relationships between the structural parameters are studied by establishing analytical models. To obtain an anastomotic compensation of the self-compensatory mechanism and an expected performance of microgripper, the structural parameters are optimally tuned based on finite-element analysis simulation. With the optimal structural parameters, simulation results indicate the effectiveness of the parasitic motion compensation of the self-compensatory mechanisms.