音叉振动式微机械陀螺输出电容的统计特性分析

STATISTICAL ANALYSIS ON OUTPUT CAPACITANCE OF TUNING FORK VIBRATORY MICROMACHINED GYROSCOPE

以一种通过体微机械加工技术制备的音叉振动式微机械陀螺为对象,基于随机摄动技术定量计算了微陀螺检测输出电容变异的统计特征,以概率思想表达微陀螺批量加工过程所带来的材料/尺寸随机误差对其性能的影响。所提出的影响因子这一概念反映了微陀螺参数变异对性能变异的敏感度。在详尽分析微陀螺众多参数的影响因子的基础上获得微陀螺5个最为关键的参数。有限关键参数的获得,不仅能为微陀螺的健壮性设计提供帮助,同时也能为实际微陀螺的加工控制提供量化的参考依据。

Focusing on a tuning fork vibratory gyroscope fabricated through silicon bulk micromachining, the matrix perturbation technology in the random finite element method is introduced to analyse the statistical characteristics of the output capacitance of tuning fork vibratory gyroscope. The influences of random material parameters and dimensional parameters on the performance of a microgyroscope are quantitatively described by a so-called impact factor based on probability. The impact factors exactly point out that the sensitivity of parameters variance to performance variance and finally bring out the five key parameters of a microgyroscope. These limited key parameters not only simplify the dimensions of design space for the robust optimization design of a microgyroscope, but also provide a special quantitative reference to the accuracy control in the fabrication procedures of the microgyroscopes.