多梁凹槽高g值加速度计的设计与分析

Design and analysis of multi-beam groove high g-value accelerometer

针对目前航空航天、车辆碰撞分析等领域对高g值加速度计的迫切需求,设计了一种新型多梁凹槽压阻式加速度计,该加速度计利用变截面梁作为敏感梁来放大质量块的等效惯性力,并通过辅助梁与背面凹槽的组合有效提高结构刚度,实现了高灵敏度输出和良好的频宽特性。建立了加速度计的力学模型,并通过ANSYS有限元软件仿真分析,优化获得了加速度计的结构和尺寸。利用敏感梁表面路径,分析总结其应力分布规律,确定压敏电阻位置。仿真实验结果表明,设计出的该加速度计量程为150000 g,灵敏度为1.32μV/g,固有频率约为268 kHz。最后基于SOI技术设计了加速度计的工艺流程。

In response to the urgent demand for high g-value accelerometers in aerospace,vehicle collision analysis and other fields,a new multi-beam groove piezoresistive accelerometer was designed,which used variable section beams as sensitive beams to amplify the equivalent inertial force of the mass,and effectively improved the structural stiffness through the combination of auxiliary beam and back groove to achieve high sensitivity output and good bandwidth characteristics.The mechanical model of the accelerometer was established,and the structure and size of the accelerometer were optimized through ANSYS finite element software.Using the surface path of the sensitive beam,the stress distribution law was analyzed and summarized,and the varistor position was determined.The simulation results demonstrate that the designed sensor measurement range was 150000 g,and the sensitivity was 1.32μV/g,and the natural frequency was about 268 kHz.Based on SOI technology,the processing flow of the accelerometer was finally designed.