四腿菱形变截面梁微加速度计结构设计与研究

在传统等截面双边四梁微加速度计结构上,以变极距式电容传感器为对象,设计一种菱形变截面梁。为增加梁的稳定性,满足加速度计对不同方向刚度要求,并提高灵敏度,建立加速度计数学理论模型,推导出灵敏度与刚度的关系。建立梁的纯弯曲模型,并基于静电驱动原理,推导出静电刚度公式,确定满足静电刚度小于机械刚度的条件下加速度计量程。结果显示,菱形变截面梁减小了梁的应力集中,使梁两方向的刚度最大化,提高了加速度计灵敏度。

Structure Design and Research of the Four-Prong Legged Micro-Accelerometer Based on Rhombic Variable Cross-Section Beam

On the basis oftraditional equal cross-section bilateral four beamsmicroaccelerometer structure,as thevariable distance capacitance sensor for object,arhombic accelerometerof variablecross-section beamwas designed.The accelerometer mathematical modelwas established to increase the stability of the beam,meet the requirements of accelerometer with different direction stiffness,improvethe sensitivity,and the relationship between sensitivity and stiffnesswas got.The pure bending model of the beamwas established,and based on the basic principle of electrostatic drive,the static stiffness formulawas derived and the accelerometer range was ensured on the condition thatthe static stiffness is less than the mechanical stiffness.The results shows that the beam stress concentration canbe reduced by using rhombicvariablecross-section beam,the stiffness of beam in two directions can be maximized,and the sensitivity can be improved.