Research On Robust Design Of Piezoelectric MEMS Sensor

With the development of micro-machining technology,MEMS sensor research has been widely attention.Piezoelectric MEMS sensor which can be multi-functional,intelligent,integrated and no auxiliary power and other advantages,has a very high application prospects.However,the characteristic size of the MEMS sensor is in the order of nanometer and micrometer,which makes the mechanical behavior and the motion law are very different from the macroscopic mechanical system.The traditional mechanical design theory is no longer suitable for the design of MEMS devices.In this paper,robust design ideas are introduced in the design of piezoelectric MEMS sensors,and the robust design method of piezoelectric MEMS sensors is studied theoretically,and the numerical calculation and simulation are carried out.In this paper,the robust design principle and modeling method of micro-sensors based on stochastic model,tolerance model and fuzzy model are studied respectively.Based on the robust design of piezoelectric properties of single nanofibers,a robust mathematical model based on tolerance model and stochastic model is established.The optimal solution of single nanofiber structure design parameters is obtained and the piezoelectric performance is improved effectively.The results show that the robust design has good agreement with the results of stochastic robust optimization,which indicates the importance of robust design in the optimization design of MEMS sensor sensitive components.It provides the ideas and methods for the robust design of the subsequent piezoelectric double crystal beam MEMS sensor.In order to avoid the blindness of the robust design process of the piezoelectric double crystal beam MEMS sensor,the design efficiency of the MEMS sensor is improved.The influence of structural parameters of piezoelectric twin crystal on its output voltage is analyzed by ANSYS simulation,and the robust design variables of piezoelectric double crystal beam MEMS sensor are selected reasonably.The influence of structural parameters on the maximum displacement of the piezoelectric twin crystal beam is discussed by ANSYS simulation.The ANSYS simulation results of the maximum displacement of the piezoelectric twin crystal beam are compared with the theoretical values of Simts.The error rate is less than 9%,which indicates that the ANSYS simulation result is correct and reliable,Which provides theoretical basis for verifying robust design results by finite element simulation.The optimization design of MEMES sensor of piezoelectric double crystal beam is studied by using the three robust design models mentioned in this paper.The controllable and uncontrollable factors in the piezoelectric twin crystal are analyzed in detail,considering the uncertainties(randomness and fuzziness)of the robust design parameters and the machining deviations in the MEMS process;to ensure the piezoelectric double crystal beam boundary Constraint,stress constraint and steadyness feasibility of strain constraint,a robust mathematical model of piezoelectric double crystal beam MEMS sensor is established and solved.Compared with the original scheme,the design results show that the robust design can improve the quality performance of the MEMS sensor and control the processing cost.When the actual dimensions of the MEMS sensor are deteriorated(within a certain range),the stability and stability of the MEMS sensor can be improved The yield of microprocessing of MEMS sensor verifies the practicability and effectiveness of robust design method.The robust design of piezoelectric double crystal beam MEMS sensor is verified by ANSYS simulation.ANSYS simulation also shows that the robust design is based on the improvement of the quality performance of the MEMS sensor,not only the overall size of the piezoelectric double crystal beam is reduced,the maximum displacement of the piezoelectric double crystal beam is also reduced,and the safety of the MEMS sensor is improved.