Simulation And Experimental Research Of MEMS Shutters For Thermal Control

As the focus of the international study, Variable Emittance Coating Instrument offers a better solution for small spacecraft thermal control. Among the VEC Instrument, MEMS shutters have a high practical value and development prospects with the advantages of light weight, low power consumption, fabrication easy to combine with IC technology, etc. In this dissertation, combining with the level of domestic fabrication technology, a two layer structure was designed. And simulation, fabrication and experimental tests were done for research.Mechanical model of the MEMS shutters was put forward at first. After the comparison of the parallel plate and comb structure drives, the displacement formula was derived and calculated. The formula showed that the comb structure is more suitable for the shutters. Finally, the structure of folded beams and equivalent emissivity were analyzed after designing initial structure of the MEMS shutters.Static analysis and modal analysis were carried out via ANSYS software. In the static analysis, the structure of shutters was simulated in order to get large displacement and appropriate stress. The results indicated that the more folded beams were in series, the smaller the beam stiffness was, the larger the displacement and the maximum stress were. In the process of modal analysis, the shutters' five-order modal shape and natural frequency were achieved. The first-order modal shape was the moving of the louver with 874.58 Hz of natural frequency.For the purpose of fabricating MEMS shutters, bulk silicon process was devised. When MEMS shutters had been produced, the results of processing proved that the structure and bulk silicon process were reasonable and feasible. Through experimental test, a variety of device parameters were obtained, such as resonance frequency of shutters, voltage-displacement functions, etc.Through the design and experimental research on MEMS shutters, profound understanding was established about the difficulty and key point of MEMS shutters. In addition, methods of design and manufacture were mastered which could improve the further research on MEMS shutters.