双质量解耦硅微陀螺仪的非理想解耦特性研究和性能测试

Non-ideal decoupled characteristics' research and system performance test of dual-mass decoupled silicon micro-gyroscope

为了分析双质量解耦硅微陀螺结构中的机械耦合误差,对微陀螺结构的非理想解耦特性进行了研究。首先,阐述了双质量解耦硅微陀螺仪的结构原理,推导了双质量解耦硅微陀螺仪的检测位移;接着构建检测框架在驱动模态下非理想的解耦模型,推导了由非理想解耦导致检测框架的平动位移与转动位移的公式;然后进行了结构非理想解耦特性仿真分析,对驱动模态时检测框架和检测模态时驱动框架的非理想运动特性进行仿真,结果表明检测框架的残余平动位移达到驱动位移的0.86%,最大转动残余位移达到了驱动位移的2.7%,而驱动框架的平动残余位移达到了检测位移的1.36%,转动残余位移达到了检测位移的0.87%;最后,对加工的双质量解耦硅微陀螺结构芯片的非理想解耦误差进行了测量,结果表明非真空封装下的正交误差达到158.65(o)/s,失调误差为19.03(o)/s,偏置稳定性达到12.01(o)/h。

The non-ideal decoupled characteristics of the micro-gyroscope structure were studied to analyze the mechanical coupling error of dual-mass decoupled micro-gyroscope. At first, the working principle of dual-mass decoupled micro-gyroscope was described, and the sense displacement of dual-mass decoupled micro-gyroscope was deduced. Then the non-ideal decoupled model of sense frame was constructed in the drive mode. The equations of the parallel displacement and rotational displacement due to the non-ideal decoupling were derived. Simulation analysis on the non-ideal decoupling in structure was implemented. The non-ideal motion characteristics of sense frame in drive mode and the drive frame in the sense mode were simulated. Simulation results show that, the residual parallel displacement of sense frame is up to 0.86% of drive displacement and the residual maximum rotation displacement of sense frame is 2.7% of drive displacement in the drive mode, while the residual parallel displacement of drive frame is 1.36% of the sense displacement and the residual maximum rotation displacement of drive frame is 0.87% of sense displacement in the sense mode. Finally, the non-ideal decoupling error of the processed structure chip of dual-mass decoupled micro-gyroscope was measured, and the results show that the quadrature error without vacuum encapsulation is 158.65（°）/s, the offset error is 19.03（°）/s, and the bias stability is 12.01（°）/h.