一种基片式光纤光栅应变增敏传感器

针对传统裸光栅直接粘贴式应变传感器应变灵敏度小的缺陷,提出了一种基片式光纤光栅应变增敏传感器,通过设计杠杆增敏结构的封装基片实现对光纤光栅的应变增敏.该传感器具有较大的应变放大机制,其测量精度与稳定性超过了裸光纤光栅.建立了该传感器的理论感知模型,并进行了与有限元仿真分析.由等强度悬臂梁标定实验可得该传感器实际应变灵敏度为6.122 pm/με,与理论结果和仿真结果一致,且线性度达到0.99998.通过动态激振实验对该应变增敏传感器的动态响应进行研究,实验结果表明该传感器能够在0～100 Hz范围内保持一致的增敏效果,能够良好的跟踪动态应变.该传感器在大型机械装备的健康监测与故障诊断方面具有良好的应用前景.

A Substrate-type Fiber Bragg Grating Strain Sensor with Enhanced Sensitivity

This paper proposed a substrate-type sensitivity enhanced fiber Bragg grating(FBG)strain sensor based on the principle of lever,to improve the defect of the traditional bare FBG strain sensor which has a low strain sensi-tivity. The designed sensor has a significant strain amplification mechanism. The strain measurement precision and stability of the developed sensor are better than the bare FBG strain sensor. The theoretical sensing model of the de-signed strain sensor was developed,and the sensing characteristic of the sensor was analyzed through finite element method( FEM) . The cantilever calibration experiments show that the experimental sensitivity of designed FBG strain sensor is 6.122 pm/με,which is consistent with the theoretical results. The linearity of the sensor is 0.99998. The designed FBG strain sensor's dynamic response was studied through the dynamic vibration experiment. The experi-mental results show that this sensor keeps consistent enhancement effect when testing the dynamic strain in the range of 0～100 Hz. This sensor has a potential application prospect in the health monitoring and fault diagnosis of large machinery and equipment.