应变传感器动态特性激光绝对法冲击校准装置

Shock Calibration Device Including Laser Velocimeter for Dynamic Characteristics of Strain Sensor

针对应变传感器动态特性缺少校准途径的问题,提出了应变传感器动态特性激光绝对法冲击校准装置,利用霍普金森杆作为动态应变激励装置,用激光测速仪和衍射光栅作为应变测量装置,霍普金森杆在冲击激励下产生梯形脉冲应变激励,激光测速仪配合衍射光栅将动态应变转换为多普勒频率信号,通过Hilbert变换及平滑滤波技术对测量信号进行分析,编制动态应变校准软件,完成了对应变传感器动态特性的校准,校准结果的不确定度满足工程测试的需求。

In view of the lack of calibration methods for dynamic characteristics of strain sensors,a shock calibration device including laser velocimeter for dynamic characteristics of strain sensor is developed. Using hopkinson bar as a dynamic strain excitation device,using laser velocimeter and diffraction grating as strain measuring device,the Hopkinson bar to generate trapezoidal pulse strain excitation under impact excitation,and the laser velocimeter with diffraction grating to convert dynamic strain into doppler frequency signal,matching dynamic strain calibration software,analyzing the doppler frequency signal by Hilbert transform and smoothing filtering technology,the calibration of dynamic characteristics of strain sensor is completed. After analysis,the uncertainty of calibration results meets the needs of engineering testing.