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

提出了用有限元方法对压电式振动陀螺仪的特性进行预测。给出了考虑旋转科氏力影响的平面振动压电薄板的有限元列式，并将其视为二维模型。利用所开发的程序，给出了三种结构的电输入导纳、振型、输出电压传输特性随旋转的变化。从理论上分析了单片式陀螺仪的发展现状，得出如下结论：1)陀螺仪的有限元模型中清楚地表达了科里奥利力的性质；2)为了提高陀螺仪的旋转灵敏度，必须选择尽可能低的振动频率；3)由于陀螺仪的旋转，简并的振动模式可以分离为上、下模；4)模式分离对电输入导纳和输出电压有影响。5)陀螺仪必须以简并模式驱动才能获得高性能。6)仿真结果表明，单片式结构的陀螺仪是一种很有前途的灵敏检测方法旋转和使用这些模式可能是有利的，因为可以消除温度变化对频率变化的影响以提高温度稳定性。温度特性是一个重要因素，可以很容易地将其影响纳入程序。

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.