Modeling and vibration analysis of quartz yaw rate sensor to reduce mechanical coupling

The reduction of the mechanical coupling intensity between driving and a detection is indispensable to improve the performance of the yaw rate sensors (gyro). We analyzed the mechanical coupling with a combination of two models, one is a static model of bending sensor beam with the geometrically cross section, and another is a dynamic model of two degrees of freedom system. This analysis proves that the origin of the mechanical coupling is a static tiny displacement of the sensor beam due to the asymmetry of the cross section, and the tiny displacement is amplified extremely by resonance effect. The relationships between the static model with asymmetric ratio of the beam´s cross section, and the dynamic model with a resonant frequency differential ratio between drive and detection modes, give the basic guideline for the designs and fabrications of yaw rate sensors