Structure Design And Simulation Of Novel Sixteen-Sided Cobweb-Like Disk Resonator Gyroscope

With the development of MEMS technology,the research of silicon-based micro gyroscopes has attracted more attention,and its application fields are expanding.In recent years,the axisymmetric MEMS gyroscopes has been highly conceerned by researchers due to their advantages of high precision,small size,low power consumption,strong anti-overload capability and integration.For traditional ring structure MEMS gyroscopes,the main problem is frequency difference caused by process errors.At present,the MEMS processing technology is accurate for the straight-line structures yet exists large error in the curve structures.The sixteen-sided cobweb-like disk resonator gyroscope(CDRG)proposed in this paper is a linear structure with good symmetry and low sensitivity to process errors.It also owns the advantages of small frequency difference,low mechanical thermal noise,high quality factor and strong seismic resistance.Firstly,structural parameters including ring width,ring number,height of resonator,anchor ratio,and radius are optimized and determined to theoretically analyze noise and mechanical sensitivity,trequency and thermoelastic damping,as well as modal frequency differences.Secondly,based on COMSOL finite element simulation analysis technology,the modal analysis,thermo-elastic quality factor,frequency difference and shock resistance of the structure were researched.The simulation results show that the optimized new structure could achieve the goal of low frequency difference and has high quality value at high frequency.At the same time,double spoke structure is proposed based on the analysis of heat flux.Simulation results show that double spoke structure can significantly reduce the surface heat dissipation and increase the thermoelastic quality value.In addition,while studying the anti-overload capability of the CDRG structure,this paper proposes a mass suspension method,which can significantly increase the effective mass ot the structure and reduce the mechanical thermal noise at the same time.Besides,the structure could survive in high-g load without any special protection,which demonstrates the feasibility and rationality of structural design.Finally,experimental results show that the processing error of the structure is small.Frequency symmetry of sixteen-sided resonator is better than traditional ring structures,and its initial frequency difference is 0.56Hz(29.9ppm).In addition,the test quality value is 113k,which approximates theoretical calculation and simulation quality factor 113k in 0.3 Pa air pressure.Test sensitivity is 1.335μm/(rad/s)and angle random walk(ARW)is 0.1°/sqrt(h).The CDRG this paper proposed meets design goals for achieving high Q at high frequencies.The dissertation also provides a theoretical reference for MEMS structural design and performance improvement.