为了减小振动环驱动模态和检测模态的频率差从而提高陀螺性能,提出了一种采用电磁驱动、电磁检测的全对称振动环陀螺结构。采用MEMS体硅工艺完成该微机械振动环陀螺的加工,其结构在保持镜像对称的同时,还保持了中心对称,因此整个结构高度对称,有利于减小模态频率差。为有效跟踪陀螺驱动模态的谐振频率并稳定驱动模态的幅值,设计了闭环驱动控制电路。该电路由低噪声前置放大器、相位调整环节以及自动增益放大器(VGA)组成。测试结果表明,该陀螺两个模态频率差为0.27 Hz ,实现了频率较好的匹配。在±200°/s ,测得陀螺灵敏度为8.9 mV/(°/s) ,分辨力为0.05°/s ,非线性度为0.23%。

To reduce the frequency split of the drive mode and the sense mode of a vibrating ring gyroscope to improve the performance of the gyroscope,a novel symmetrical structure with electromagnetic driving and detection is proposed in this paper. The Micro-machined Vibrating Ring Gyroscope (MVRG) is fabricated in centro-symmetric and mirror-symmetric micro structures by MEMS bulk silicon processing with (100) oriented single-crystal silicon,which is conductive to reducing the frequency split. A closed-loop control circuit consisting of a low noise front-end amplifier,a phase shifter and a Variable Gain Amplifier (VGA) is developed to track the drive mode resonant frequency and to stabilize the vibration amplitude of the drive mode. The test results show that the frequency split of drive mode and the sense mode is about 0.27 Hz,which means the frequencies have been matched well. The sensitivity of this gyroscope is 8.9 mV/(°/s) ,the resolution is 0.05°/s and nonlinearity is about 0.23% in the rotation rate ranges of ±200 °/s.