Design Optimization for a Parallel MEMS Mechanism with Flexure Joints

This paper presents an analysis tool and design method forMEMS parallel mechanisms. Due to processing constraints inMEMS fabrication, flexure joints are frequently used in MEMS mechanisms. Flexure joints offer advantages over other joint design due to their monolithic characteristics. They can be used to reduce the size of manipulators or to increase the precision of motion. Their inherent flexibility, however, also results in task space compliance which needs to be carefully designed to match the task specification. This paper presents an analysis and design tool for such mechanisms by using the differential kinematics.Performance metrics are chosen based on manipulability and task stiffness matrices, which in turn are used in a multi-objective optimization. As an illustrative example, a 1-DOF MEMS parallel mechanism based on the macro- and meso-scale models designed by NIST is considered with several choices of performance metrics and design variables. The resulting designs are successfully fabricated using DRIE process.