研究了一种能够在大气压下达到较高性能的微机电陀螺敏感结构。设计了一种用于敏感垂直于结构平面方向的角速度的、驱动轴和检测轴相似的线振动微机电陀螺敏感结构。用U形梁隔离驱动器、敏感质量块和检测器以降低机械耦合，检测轴采用变面积式检测电容以降低阻尼。推导了振动速率陀螺的机械频率响应特性，分析了机械热噪声和在调谐及非调谐模式下检测电路噪声等效的角速度噪声，分析了梁的刚度矩阵和机械耦合特性，测试了结构的驱动-检测耦合频率响应。在大气压下陀螺检测轴品质因数达到66，机械热噪声为1.89((°)·h-1)/√Hz，理论耦合刚度比大于800。%A MEMS gyroscope structure is studied, which has relatively high performance in atmospheric pressure. U-shaped beams are adopted to isolate the driving comb, proof mass, and sensing comb. The sensing and driving axes have identical mechanical layout. The mechanical frequency response from angular rate to demodulated displacement is deducted, the equivalent angular rate noise caused by the mechanical thermal noise is illustrated, and the sensing circuit noises in tuned and untuned operating modes are compared. The stiffness matrix of the beams is presented, and the coupling frequency response is measured. It is shown that the sensing axis’sQ-factor is 66 in atmosphere, and mechanical thermal noise of 1.89 ((°)·h-1)/√Hz is obtained. Theoretical coupling-to-primary stiffnessratio can be over 800.
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