基于PZT管支撑结构的三轴加速度计设计及实验误差分析

Design and experimental error analysis of the 3-axis accelerometer based on PZT-tube support structure

以提升毫米尺度三轴压电加速度计灵敏度为目标,设计了以3个长度12 mm轴向极化的PZT管作为敏感和支撑结构的三轴加速度计,给出了空间加速度信号的解算方法。通过3个PZT管关于器件结构中心轴对称布置,该加速度计实现了对三轴加速度大小和方向的精确解算。数值仿真得到了3个PZT管在[100,1000]Hz加速度的输出电压幅频特性曲线及器件三轴灵敏度。研制了三轴传感器样件,实验表明其x、y、z轴灵敏度分别为535、541、542 mV/g,三轴灵敏度标准差为3.8。系统分析了加工误差对实验结果的影响程度,分析并解释了实验与仿真数值间存在误差的原因,为三轴加速度计敏感与支撑结构的一体化设计提供了借鉴。

To increase the sensitivity of the millimeter scale triaxial piezoelectric accelerometer,a tri-axis accelerometer with sensitive and support structure of three 12 mm-length axial polarized PZT tubes is designed.The calculating method of spatial acceleration is provided.The output voltage amplitude-frequency characteristic curve of 3 PZT tubes during[100,1000]Hz acceleration and tri-axis sensitivity are achieved by numerical simulation.Three PZT tubes are deployed symmetrically around the center of the device to realize the accurate calculation of the magnitude and direction of the triaxial acceleration.A triaxial sensor sample is developed.Experimental results show that the 3-axis sensitivity values are 535,541 and 542 mV/g,respectively.The influence degree of machining error on experimental results is analyzed systematically.The error between experimental value and simulation value is analyzed and explained.The high sensitivity sensor provides a reference for the integrated design of triaxial accelerometer′s sensitivity and support structure.