基于振动模态的微器件结构设计评价方法

Structural Design Evaluation for Micro Devices Based on Vibration Modes

为了提高微器件的设计效率,提出一种微器件的结构新型设计评价方法。首先,根据理论分析获得微机械陀螺结构设计原则,以典型两质量块微机械陀螺为研究对象,利用有限元工具与模态分析相结合,获得该系统固有频率和相应的振型矩阵;然后,利用模态叠加法求各阶模态对于驱动振动和检测振动的贡献度,并采用能量法分析各阶模态对系统的影响;最后,针对两类音叉式微机械陀螺具体实例模型,分别获得系统各阶模态能量在频域上的分布情况,证明所提出的微结构设计评价方法的正确性。

To improve the efficiency of micro devices design, a new method of structural design evaluation for micro devices is proposed based on the micromachined gyroscope that is one of the typical micro devices. The principle of evaluation is achieved due to the theory analysis. Based on a typical 2-mass micromachined gyroscope, the natural frequency and corresponding model matrix can be obtained by the combination of FEM tools and mode analysis, then the contribution of each mode is achieved by modal superposition, and the effect of each mode is studied in the view of the energy. Finally, the energy distribution in frequency domain of each mode for two types of tuning fork micromachined gyroscope is obtained, and the method of structural design evaluation is consequently validated.