考虑粘贴型光纤布拉格光栅(FBG)测量受弯件时测试效果易受到粘贴参数的影响, 研究了受弯件的粘贴型FBG的应变传递规律。首先, 通过理论分析建立了受弯件粘贴型FBG应变传递模型, 确定了相关影响参数; 然后, 利用仿真法分析了影响应变传递的各个参数; 最后, 通过实验分析验证了理论与仿真分析结论。实验与仿真对比分析表明: 黏胶长度与黏胶中间层厚度是影响受弯件粘贴型FBG应变传递率的主要因素; 黏胶的高度/宽度对应变传递率的影响较小, 测试的静态特性指标相近, 应变传递率分别在96%/95%上下小范围内波动。黏胶长度大于FBG名义长度2倍时, 静态特性明显优于黏胶长度较短者, 实验应变传递率约为95%。FBG的应变传递率随黏胶中间层厚度的增大而上升, 甚至超过100%, 可用于对粘贴型FBG传感器的增敏。获得的结论对采用粘贴型FBG对受弯件进行高精度测试具有指导意义。

When pasted Fiber Bragg Gratings (FBGs) are used to measure bending parts, the testing results are easily affected by paste parameters. This article researches the strain transfer factors of a pasted FBG under bending parts. Firstly, a pasted FBG strain transfer model was established by theoretical analysis, and the related parameters were determined. Then, the strain transfer parameters were qualitatively analyzed by a simulated analysis method. Finally, the results of theory and simulated analysis were verified by an experimental analysis. The experiment and simulation results show that the length and the middle layer thickness of glue have dominating effects on FBG strain transfer rate under bending parts. The thickness/width of glue are secondary factors, they have a similar result for static properties, and there are small fluctuations near by 96% / 95%, respectively.When the length of glue is more than 2 times of FBG length, its static properties are obviously better than that of shorter length, and the strain transfer rate is about 95%. Moreover, the strain transfer rate of the FBG rises with the augment of middle layer thickness, sometimes even more than 100%, so it can be used to enhance the sensitization of a pasted FBG sensor. In the conclusion, the results offer a guidance for the high precision measurement of bending parts by the pasted FBGs.