Research On The Two-dimensional Micro-displacement Positioning Platform System Integrated MEMS Capacitive Displacement Sensor

With the development of science and technology, micro-displacement positioningtechnology has become the basic technologies of many modern High-tech equipment,High-precision positioning platform systems are widely used in aerospace, ultra-precisionmanufacturing and measurement, microelectronics, bio-engineering, optical engineeringand other fields. This subject for that the big platform body, high couple of themicro-displacement positioning platform system, and the displacement sensors is difficultto achieve miniaturization and high integration, especially the installation and adjustmentof displacement sensor is not easy to ensure, optimized the design of themicro-displacement positioning platform and designed the comb capacitive displacementsensor for two-dimensional positioning platform.This paper first did the overall design to determine the size of the overall structure ofthe micro-displacement positioning platform; Designed the sheet parallel flexibledecoupling beam to suppress the coupling of the two-dimensional micro-displacementpositioning platform; Made the structures in micro-displacement positioning platform havereasonable layout, using one level displacement amplification mechanism to amplify thedrive displacement effectively, while change the driving displacement direction; Designedthe preload program of the piezoelectric ceramic actuator using fine pitch screw combinedwith wedge mechanism; Finally, using the ANSYS analysis software to simulate andanalyze the designed positioning platform.Designed the comb capacitive micro-displacement sensor silicon-based MEMSprocess, considering the integration with the above-mentioned micro-displacementpositioning platform, did the overall design for comb capacitive displacement sensor; Byanalysis and calculation to determine the parameters of the comb-tooth electrode structureof the sensor, the comb-tooth electrode spacing and the structure of the flexible beam;Using the ANSYS analysis software to simulate and analyze the designed comb capacitivedisplacement sensor; Finally, identified the process of the silicon-based MEMS comb capacitive sensor.Established the control systems based the algorithm of feed-forward control combinedwith PID, This control system consists of piezoelectric actuators and drive power, combCapacitive Displacement sensor, capacitance signal conversion circuit and controlcomputer, Thus ensured the micro-displacement positioning platform system has goodcontrol accuracy.Finally, build a lab test systems, test the output displacement, resolution, coupling andfrequency of the micro positioning platform to verify the real micro positioning platformdo or don’t achieve the design specifications.