微机械陀螺正交耦合误差静电力抑制的有限元仿真研究

The FEM Analysis of Electrostatic-force Suppression of Quadrature Coupling Error in a MEMS Gyroscope

微机械陀螺的正交耦合误差是敏感结构振动模态间的刚度耦合引起的检测模态输出偏量,是影响陀螺性能的关键误差源之一。静电力抑制是一种采用静电力调节驱动模态的主轴偏量,使用直流电压进行正交耦合误差抑制的方法,该方法具有片上实时抑制能力,能够有效抑制正交耦合误差。从静电力抑制正交耦合误差的基本原理出发,运用有限元仿真,对硅基音叉陀螺正交耦合误差的静电力抑制进行了仿真分析,并通过实物测试数据进行了验证。

As an sensing mode output deviator caused by stiffness coupling between vibration modes of sensing structures, quadrature coupling error is one of the key error sources that influence the performance of a MEMS gyro. Electrostatic-force suppression, using DC voltage to adjust the misalignment of the mode principle axis, is one of the most effective ways to eliminate quadrature coupling error, which has on-chip and real-time adjustment capability. Based on the theory and FEM analysis of electrostatic-force suppression, this paper demonstrates detailedly the FEM analysis for a typical silicon tuning fork gyro and the experimental verifications of this analysis.