梳齿倾斜角对多自由度微陀螺动态性能的影响

Effects of comb inclination angle on dynamic performance of multi-DOF micro-gyroscope

为揭示由于刻蚀加工误差导致的梳齿倾斜角度对多自由度微陀螺动态性能的影响机理,以一类四自由度静电驱动微机械陀螺为研究对象,分析了线性及静电力非线性工况下梳齿倾斜角度对微陀螺动力学特性的影响。研究结果表明,微陀螺在线性系统内工作时,梳齿倾斜角会导致微陀螺系统出现共振频率偏移,并造成灵敏度大幅下降,但对带宽基本没有影响。当在静电力非线性系统内工作时,梳齿倾斜角对系统响应有刚度硬化作用,可在一定程度上抵消静电力非线性的影响;硬化作用先随梳齿倾斜角的增加而增加,到达峰值后随刻蚀误差的增加而减小,即存在最佳梳齿倾斜角度以抵消静电力非线性的影响。上述研究成果为控制或利用刻蚀误差的影响提供了理论依据。

Here,to reveal influence mechanism of comb inclination angle caused by etching error on dynamic performance of multi-DOF micro gyroscope,taking a kind of 4-DOF electrostatically driven micromachined gyroscope as the study object,effects of comb inclination angle on dynamic characteristics of the micro-gyroscope under linear working conditions and nonlinear electrostatic force ones were analyzed.The results showed that when the micro-gyroscope works in a linear system,comb inclination angle can cause resonance frequency offset in the micro-gyroscope system and the sensitivity can be greatly reduced,but it basically doesn’t affect the system’s bandwidth;when the micro-gyroscope works in a nonlinear electrostatic force system,comb inclination angle has a stiffness hardening effect on the system response,this effect can offset effects of electrostatic force nonlinearity to a certain extent;the hardening effect firstly increases with increase in comb inclination angle,and then decreases with increase in etching error after reaching its peak,i.e.,there is an optimal comb inclination angle to offset effects of electrostatic force nonlinearity;the study results can provide a theoretical basis for controlling or using effects of etching error.