School of Mechanical and Electronic Engineering, Wuhan University of Technology, Wuhan 430070, China.
School of Engineering, University of Birmingham, Birmingham B15 2TT, UK.
Sensors (Basel). 2018 May 17;18(5):1607. doi: 10.3390/s18051607.
A novel fiber Bragg grating (FBG)-based strain sensor with a high-sensitivity is presented in this paper. The proposed FBG-based strain sensor enhances sensitivity by pasting the FBG on a substrate with a lever structure. This typical mechanical configuration mechanically amplifies the strain of the FBG to enhance overall sensitivity. As this mechanical configuration has a high stiffness, the proposed sensor can achieve a high resonant frequency and a wide dynamic working range. The sensing principle is presented, and the corresponding theoretical model is derived and validated. Experimental results demonstrate that the developed FBG-based strain sensor achieves an enhanced strain sensitivity of 6.2 pm/με, which is consistent with the theoretical analysis result. The strain sensitivity of the developed sensor is 5.2 times of the strain sensitivity of a bare fiber Bragg grating strain sensor. The dynamic characteristics of this sensor are investigated through the finite element method (FEM) and experimental tests. The developed sensor exhibits an excellent strain-sensitivity-enhancing property in a wide frequency range. The proposed high-sensitivity FBG-based strain sensor can be used for small-amplitude micro-strain measurement in harsh industrial environments.
本文提出了一种基于新型光纤布拉格光栅（FBG）的应变传感器，具有高灵敏度。所提出的基于 FBG 的应变传感器通过将 FBG 粘贴在具有杠杆结构的基底上来提高灵敏度。这种典型的机械结构通过机械方式放大 FBG 的应变，从而提高整体灵敏度。由于这种机械结构具有高刚度，因此所提出的传感器可以实现高谐振频率和宽动态工作范围。介绍了传感原理，并推导和验证了相应的理论模型。实验结果表明，所开发的基于 FBG 的应变传感器实现了增强的应变灵敏度为 6.2 pm/με，与理论分析结果一致。开发的传感器的应变灵敏度是裸光纤布拉格光栅应变传感器的应变灵敏度的 5.2 倍。通过有限元方法（FEM）和实验测试研究了该传感器的动态特性。所开发的传感器在宽频率范围内表现出优异的应变灵敏度增强特性。所提出的基于高灵敏度 FBG 的应变传感器可用于恶劣工业环境中的小振幅微应变测量。
