The theory of eigenmode operation of Coriolis vibratory gyroscopes and its implementation on a thin-film piezoelectric gyroscope is presented. It is shown analytically that the modal alignment of resonant gyroscopes can be achieved by applying a rotation transformation to the actuation and sensing directions regardless of the transduction mechanism. This technique is especially suitable for mode matching of piezoelectric gyroscopes, obviating the need for narrow capacitive gaps or DC polarization voltages. It can also be applied for mode matching of devices that require sophisticated electrode arrangements for modal alignment, such as electrostatic pitch and roll gyroscopes with slanted electrodes utilized for out-of-plane quadrature cancellation. Gyroscopic operation of a 3.15 MHz AlN-on-Si annulus resonator that utilizes a pair of high-Q degenerate in-plane vibration modes is demonstrated. Modal alignment of the piezoelectric gyroscope is accomplished through virtual alignment of the excitation and readout electrodes to the natural direction of vibration mode shapes in the presence of fabrication nonidealities. Controlled displacement feedback of the gyroscope drive signal is implemented to achieve frequency matching of the two gyroscopic modes. The piezoelectric gyroscope shows a mode-matched operation bandwidth of ~250 Hz, which is one of the largest open-loop bandwidth values reported for a mode-matched MEMS gyroscope, a small motional resistance of ~1300 Ω owing to efficient piezoelectric transduction, and a scale factor of 1.57 nA/°/s for operation at atmospheric pressure, which greatly relaxes packaging requirements. Eigenmode operation results in an ~35 dB reduction in the quadrature error at the resonance frequency. The measured angle random walk of the device is 0.86°/√h with a bias instability of 125°/h limited by the excess noise of the discrete electronics.

介绍了科里奥利振动陀螺仪的本征模式工作原理及其在薄膜压电陀螺仪上的实现。分析表明，谐振陀螺仪的模态对齐可以通过对驱动和传感方向应用旋转变换来实现，而不管转换机制如何。该技术特别适用于压电陀螺仪的模式匹配，无需窄电容间隙或直流极化电压。它还可以应用于需要复杂电极布置以进行模式对齐的设备的模式匹配，例如带有用于平面外正交消除的倾斜电极的静电俯仰和滚动陀螺仪。3.15 MHz AlN-on-Si 环形谐振器的陀螺仪操作，该谐振器利用一对高问演示了退化的面内振动模式。压电陀螺仪的模态对准是通过在存在制造不理想情况下将激励和读出电极虚拟对准振动模式形状的自然方向来实现的。实现陀螺驱动信号的可控位移反馈，实现两种陀螺模式的频率匹配。压电陀螺仪显示出~250 Hz 的模式匹配操作带宽，这是模式匹配 MEMS 陀螺仪报告的最大开环带宽值之一，由于高效的压电转换，其运动电阻约为 1300 Ω，并且在大气压下运行的比例因子为 1.57 nA/°/s，这大大放宽了封装要求。本征模式操作导致谐振频率处的正交误差减少约 35 dB。测得的器件角度随机游走为 0.86°/√h，偏置不稳定性为 125°/h，受分立电子器件的过量噪声限制。