Energy Loss in a MEMS Disk Resonator Gyroscope.

Xie Xie,Yuan Yuan,Hao Hao

doi:10.3390/mi10080493

Abstract

Analysing and minimizing energy loss is crucial for high performance disk resonator gyroscopes (DRGs). Generally, the primary energy loss mechanism for high vacuum packaged microelectromechanical system (MEMS) resonators includes thermoelastic damping, anchor loss, and electronic damping. In this paper, the thermoelastic damping, anchor loss, and electronic damping for our DRG design are calculated by combining finite element analysis and theoretical derivation. Thermoelastic damping is the dominant energy loss mechanism and contributes over 90% of the total dissipated energy. Benefiting from a symmetrical structure, the anchor loss is low and can be neglected. However, the electronic damping determined by the testing circuit contributes 2.6%–9.6% when the bias voltage increases from 10 V to 20 V, which has a considerable impact on the total quality factor (Q). For comparison, the gyroscope is fabricated and seal-packaged with a measured maximum Q range of 141k to 132k when the bias voltage varies. In conclusion, thermoelastic damping and electronic damping essentially determine the Q of the DRG. Thus, optimizing the resonance structure and testing the circuit to reduce energy loss is prioritized for a high-performance DRG design.

Highlights

Microelectromechanical system (MEMS) gyroscopes, which are used to detect rotation angle or angular velocity, have been researched and developed for 30 years
Similar to the hemispherical resonator, the disk resonator gyroscopes (DRGs) can benefit from a high quality factor (Q), including a higher signal-to-noise ratio (SNR), better zero-bias stability, and lower power consumption [11]
The DRG is fabricated by SOG instead of SOI technology Mfoircroammachoinrees f2l0e1x9i,b1l0e, 4p93rocess

Summary

Introduction

Microelectromechanical system (MEMS) gyroscopes, which are used to detect rotation angle or angular velocity, have been researched and developed for 30 years. The DRG, which includes compact planar rings with central support and a distributed electrode, was inspired by hemispherical resonators [10]. The primary energy loss mechanisms of the resonator are thermoelastic damping, anchor loss, air damping, and surface loss [13]. Thermoelastic damping is caused by the temperature variation of the vibratory thin beams, which probably determine the Q of the vacuum packaged resonator [14]. Glected, the energy loss mechanism may affect the Q of the entire resonance system. TThhee ggeeoommeettrryy ooff tthhee ddeessiiggnneedd DDRRGG iiss sshhoowwnn iinn FFiigguurree 11,, whheerree thee embeddddeedd eelleeccttrrooddeess aarree rreemoved ffor ccllaarriittyy. Thee primaarryy ddeessiiggnn ppaarraammeetteerrss ooff tthhee ddeessiiggnneedd DDRRGG aarree lliisstteedd iinn TTable 1.

Anchor Loss

Electronics Damping

Findings

Verification and Discussion

Conclusions