一种有效提高真空封装硅微陀螺仪机械稳定性的方法

An Effective Method for Improving Mechanical Stability of Vacuum Silicon Micro-Gyroscope

本文提出一种有效提高真空封装硅微陀螺机械稳定性的方法.通过谐振增益与模态频差的参数灵敏度关系可知,随着模态频差的增大,机械谐振增益对模态频差的灵敏度减小,外界环境引起的模态频差的微弱抖动量决定驱动、敏感模态频率差的设计极大值,因此当频差设计值的变化量等于外界引起的频差抖动量且谐振增益满足应用需求时,真空封装硅微陀螺的机械稳定性达到最优.仿真结果表明机械稳定性提高12.7%,最佳封装气压约为5.3 kPa.实测结果表明,零漂提高到0.9 mV时,刻度因子的线性度为700×10-6,带宽提高3倍,约为89 Hz.该方法为真空封装硅微陀螺仪的参数优化提供了理论依据.

In this paper, an effective method for improving the mechanical stability of vacuum silicon mi- cro-gyroscope was proposed. A relationship between gain sensitivity to variation of parameter and mode separation demonstrated that the sensitivity decreased with the increase of mode separation, and slight fluctuation of mode separation caused by external disturbances dominated the maximum designed value of frequency difference. So the mechanical stability was optimized when the variation of designed value of frequency difference was equal to the fluctuation of mode separation and mechanical gain met application requirement. The simulation results showed that the mechanical stability was enhanced by 12.7% , and the optimum packaging pressure was about 5.3 kPa. The test results demonstrated that the zero drift was approximately improved to 0.9 mV with the nonlinearity of scale factor being 700 ×10^-6. The bandwidth was improved by 3 times, reaching 89 Hz. This method may provide theoretical foundations for the structure parameter optimization of vacumn silicon micro-gyroscope.