高过载三维MEMS加速度传感器敏感芯片设计仿真与优化

为获取硬目标侵彻武器弹体侵彻过程中完整的三轴向加速度信号，研制了三维高冲击过载MEMS压阻式加速度传感器。提出了中心岛硬心质量块E型膜片结构设计方案和独特的三维力敏电阻的布桥方式，并详细阐述了传感器三维加速度测试的工作原理，运用有限元分析软件进行仿真验证，并运用零阶粗优化与一阶梯度寻优相结合的优化算法，对传感器敏感芯片的结构参数进行优化。优化仿真结果表明：传感器敏感芯片的结构强度足够，可承受的瞬态高冲击过载峰值最高可达2×105 g;芯片固有频率可达231 kHz;三轴向加速度浏试力敏电阻布设位置应力应变大，使得传感器有较高的输出灵敏度，理论上的优化仿真分析保证了传感器有可靠的工作性能，最后研制传感器原理样机，进行实验验证。

Design, Simulation and Optimization of Sensing Chip of High-g Three-axis MEMS Accelerometer

High-g three-axis MEMS piezoresistive accelerometer was developed in order to measure in?tegrated accelerometer signal of the penetration process of the body oi the missile of hard-target pene?tration weapon. A new design project of E shape diaphragm structure of central single proof mass of accelerometer was put forward. The accelerometer’s structure and working principle were discussed in details. This design can measure the acceleration in three-axis directions by means of three sets of Wheatstone bridges which are disposed on the sense chip reasonably. The perfectly structural size of the sense cnip was fixed by finite element analysis software. Simulation and optimization of the sense chip were implemented, by zero-order rough optimization algorithm and first-order gradient algorithm. The results indicate that the sensing chip of triaxial accelerometer have great capability of bearing over loading under 2 X IO5 g's peak shock acceleration, the property of high frequency response with 231 kHz, high sensivity and so forth. Finally, the prototype of triaxial accelerometer is developed. The initial tests verify that the accelerometer can fulfill high-g three-axis acceleration measurement.