A Basic Study of High-accuracy Piezoelectric Vibrator Gyroscopes of Hybrid Type

本文提出用有限元法预测压电陀螺的特性。本文给出了二维压电薄板平面振动的有限元列式，该列式考虑了转动引起的科氏力的影响。利用所编制的程序，对三种结构的输入电导纳、模态振型、输出电压传输特性随旋转的变化进行了计算。考虑到单片式陀螺仪的发展，从分析中可以得出以下结论：1）哥氏力的特性在陀螺仪的有限元公式中得到了清楚的表达; 2）为了获得高的旋转灵敏度，必须选择尽可能低的振动频率; 3）由于旋转，简并模式分离为上模式和下模式; 4）模式分离影响电输入导纳和输出电压; 5）为了获得高的性能，必须在简并模式下驱动陀螺仪。6）模拟结果表明，单片结构是有希望的灵敏检测旋转和使用这些模式可能是有利的，因为温度变化对频率的影响可以取消改变以改善温度稳定性。温度特性是一个重要的因素，其影响可以很容易地纳入程序中。

The use of the finite element approach is proposed for the characteristic prediction of piezoelectric vibrator gyroscopes. The finite element formulation including the effect of Coriolis force due to rotation is given for a piezoelectric thin plate in plane vibration, which is considered to be of a two-dimensional model. Using the program developed, the electric input admittance, the modal shapes, the change of the transmission characteristic of the output voltage due to rotation are demonstrated for three types of configuration. The development of monolithic type gyroscopes are kept in mind.The following could be deduced from the analysis :1) The proper of Coriolis force is clearly represented in the finite element formulation for the gyroscopes.2) The vibratory frequency must be chosen as low as possible for high sensitivity to rotation.3) The degenerated modes separate into the upper and lower mode due to the rotation.4) The mode separation affects the electric input admittance and the output voltage.5) The gyroscopes must be driven at the degenerated mode for high performance.6) The simulated results show that the monolithic configurations are promising for sensitive detection of rotation and the use of these modes is possibly advantageous as the effect of the temperature change on the frequency change could be canceled to improve the temperature stability. The temperature characteristic is an important factor, and the effect can easily be incorporated in the program.