The Design And Fabrication Of Compliant Electrothermal Microgripper

Microgripper is one of the key elements in MEMS, it acts an important role in microrobotics and microassembly for handling and manipulating microobjects. The design of microgripper is first discussed in this thesis, the method of type synthesis of kinematic chain and the conception of Pseudo-rigid-body model are applied on the design. Eight new microgrippers are obtained, the fabrication process and test are studied.By way of comparing the different actuations of microgrippers, electrothermal is chosen as the actuation of the microgripper. Based on the property of electrothermal microgripper, the topology requirements of rigid mechanisms which can be transformed to microgrippers are summarized. Combining Pseudo-rigid-body model with type synthesis of kinematic chain, eight new microgrippers are designed, the performance are discussed, some microgrippers are modified and optimized, thus microgrippers whose type are same but structure different have different performance. The factors which affect the output displacement of V-shaped actuator are analyzed in theory.Performance analysis of microgrippers and actuator are achieved by Coventor Ware. The geometric parameters of V-shape actuator are obtained. The output displacement, clamping force and temperature of microgripper are analyzed.The UV-LIGA fabrication process are studied, the detailed parameters and notice have been given. Six type microgrippers are fabricated.The test experiment is set up, and the performance of microgrippers is tested, and results are discussed, it indicates that these microgrippers achieve the design requirments.The design method and fabrication process in this thesis have a common sense and can be applied to other MEMS devices.