Design And Implementation Of High Overload Triaxial Wheel Ring MEMS Gyroscope

Many new forms of gyroscope structures have emerged in the continuous development of gyroscopes.The angular rates detected by the gyroscope also increased from single-axis to multi-axis.MEMS gyroscope developed based on MEMS(MicroElectro-Mechanical Systems)is widely used in aviation,aerospace,military and other fields due to its small size,low cost,and high reliability.In military applications,MEMS gyroscopes,as inertial sensors,play a massive role in missile guidance.However,when applied to high overload environments,the gyroscope will fail due to structural damage,electrical failure,and other problems.Therefore,developing a gyroscope sensitive to multi-axial angular rate and having a specific anti-high overload ability is a trend.This paper introduces a new wheel-ring tri-axis gyroscope with high overload resistance,explores its working principle,and designs and optimizes its structure.The corresponding process is designed according to the form of the gyroscope.Finally,a sample of the wheel-ring tri-axis gyroscope is obtained and tested for high overload resistance.Firstly,the general shape of the designed structure is determined by analyzing the research status at home and abroad.Its dynamic equation and impact resistance model are analyzed to provide a theoretical model for the structure’s design.Then the basic driving detection principle and the elastic beam analysis of the sensitive part are introduced.The specific size is further determined by parametric scanning.Finite element software simulates its modal,harmonic response,gravity load,high overload resistance,and thermal stress.The simulation results show that the gyroscope’s X/Y axis and Z-axis driving frequencies are 5954.8 Hz and 10 728 Hz,respectively.The sensing frequencies of the X,Y,and Z axes are 6030.5 Hz,5774.5 Hz,and 10 725 Hz,respectively,and they can withstand the impact of 10 000 g.The DDSOG(Deep Dry Silicon on Glass)process was used to fabricate silicon wafers to obtain a better gyroscope.Silicon/glass anode bonding technology was used to connect the silicon substrate closely.After vacuum encapsulation of the fabricated gyroscope,the natural frequency was tested.It was obtained that the natural frequency of the wheel structure driving mode was 5888.4 Hz,the X and Y sensing modes were 5639.0 Hz and 5936.3Hz,respectively,and the natural frequency of the ring structure driving mode was 10105 Hz.The natural frequency of the sensing mode is 10 099 Hz,and its capacitance is tested.To verify the high overload resistance of gyroscope samples,Machete hammer impact tests were carried out,after 11 600 g impact on gyroscope samples,the surface morphology,surface stress and driving mode frequency of gyro structure samples before and after impact were compared..The feasibility and rationality of the three-axis MEMS gyroscope design scheme are verified.