DESIGN AND ANALYSIS OF AN ELECTRO-THERM ALLY DRIVEN LONG-STRETCH MICRO DRIVE WITH CASCADED STRUCTURE

摘要

A single micro actuator usually can provide only limited output force and displacement. Therefore, proper integration of several basic actuators into an arrayed structure becomes an attractive way to magnify the output. Here an electro-thermally driven large-stretch micro drive (LSMD) with cascaded compliant structure and compact size (about 2000 μm x500 μm) is designed and analyzed. Two kinds of materials, polysilicon and electroplated nickel, are used in finite element simulations. From simulations, several design parameters are found to have significant influence on the output displacements. The simulated output displacements can achieve over 100 μm and 200 μm for polysilicon-made and nickel-made LSMDs respectively. Larger out-stretching displacements are feasible by proper choice of design parameters. Preliminary fabrication and testing results of nickel-made LSMDs are also presented.