FBG位移传感器的标定与不确定度分析

Calibration and uncertainty analysis of FBG displacement sensors

为了提高光纤Bragg光栅(FBG)位移传感器标定精度和实现自动标定,设计一种量程为18 cm的FBG位移传感器校准装置对FBG位移传感器进行在线校准。通过对FBG解调仪测量的波长量和计算得出的位移量进行最小二乘法拟合得到FBG传感器的静态标定系数,并对标定装置和传感器进行不确定度评定。实验结果表明:FBG位移传感器标定平台标定得到FBG位移传感器的灵敏度为0.014 5 nm/mm,线性度为99.87%,重复性误差为0.082%,校准装置的测量不确定度为0.11 mm。

In order to improve calibration precision of fiber Bragg grating（ FBG） displacement sensor and achieve automatic calibration,FBG displacement sensor calibration devices which range of 18 cm are designed to calibrate FBG displacement sensor online. Static calibration coefficients of FBG sensor are obtained by using least square fitting method for wavelength measured by FBG demodulation device and displacement got by calculation,and conduct uncertainty evaluation for calibration device and sensor. Experimental results show that the sensitivity,linearity and repeatability error of FBG displacement sensor which got by the FBG displacement sensor calibration platform are 0. 0145 nm / mm,99. 87 %,0. 082 %,respectively,the uncertainty of measurement of calibration device is 0. 11 mm.