冲击载荷作用下压阻式微加速度计的动态力学响应研究

Study on Dynamic Mechanical Behavior of Piezoresistive Accelerometers Under Shock Loading

针对目前判断器件的可靠性实验中存在成本高、周期长的问题,对微型压阻式加速度计在冲击载荷作用下的动态力学响应特性进行研究,获得微加速度计在冲击载荷作用下的动态力学响应规律。以锥形头部弹体为例构建动力学模型,对典型的微加速度计和冲击载荷工况进行理论研究,分析压阻式微加速度计在冲击载荷作用下的动态力学响应特性。结果表明:压阻式微加速度计在冲击载荷下的响应由应力波的渡越时间、结构的本征振动周期及脉冲的持续时间这3个时间常数及其关系决定,可准确反应弹体所受冲击载荷的特性。

Aiming at high cost and long duration problems of tests to analyze the reliability of devices, the dynamic response of piezoresistive accelerometers under impact loadings is investigated, and the nature of the mechanical responses of shock-loaded piezoresistive accelerometers could thus be obtained. Taking projectiles with conical head shape as examples for creating dynamic models, theoretical studies on typical piezoresistive accelerometers and shock loads are conducted, and the response of the piezoresistive accelerometers are analyzed. Results show that the response of the shock-loaded piezoresistive accelerometers is determined by three constants, viz. the acoustic transit time, the time period of vibrations and the duration of the applied shock load, and the relationship among these constants, which can accurately show the characteristics of impact loadings subjected by the projectiles.