减小交叉耦合的三维微加速度计的设计

介绍了一种减小交叉耦合的三维微加速度计的设计,该设计采用全差分电容式结构,X轴和Y轴采用梳齿电容式加速度计,Z轴采用扭摆电容式加速度计,三个轴向各自具有不同的敏感质量块,能够有效减小交叉耦合度。通过公式计算得到三个轴向的机械噪声,X轴为-60μg/Hz,Y轴为-66μg/Hz,Z轴为-53μg/Hz。从计算结果来看,三个维度的噪声系数较低,在电路噪声保证足够小的情况下,该三维微加速度计能够达到较高的精度。最后,采用COMSOL MULTIPHYSICS软件对该结构三个维度进行了模态仿真,仿真结果表明该设计能够有效减小三个维度的交叉耦合度。

Design of Low Cross-Coupling Triaxial Micro Accelerometers

The design of a low cross-coupling triaxial micro accelerometer was introduced.The differential capacitance structure was applied in the design.The comb capacitance accelerometer were adopted on the X axis and Y axis,the torsion pendulum capacitance accelerometer was used on the Z axis.The different sensitive masses were along the three axes,respectively,debasing the cross-coupling effectively.The machine noises of three axes were calculated by formulas,-60 μg/ Hz on the X axis,-66 μg/ Hz on the Y axis,and-53 μg/ Hz on the Z axis.The results show that the noise figures in three dimensions are lower,and the triaxial micro acce-lerometer can achieve higher precision under enough low circuit noise.At last,the micro acce-lerometer structures in three dimensions were simulated by using COMSOL MULTIPHYSICS software.The simulated results show that the design can reduce the cross-coupling in three dimensions effectively.