Strain transferring mechanism analysis of the substrate-bonded FBG sensor

One of the important application forms of Fiber Bragg grating (FBG) is to measure strain by pasting on the surface of structure. In order to improve the strength of surface-bonding FBG, packaging substrate in metal slice is designed and applied. On the basis of previous studies, an analytic model of the substrate-bonded FBG sensor is developed to predict the strain transfer rate. Moreover, the effects of substrate material and sizes on the strain transfer rate of substrate-bonded FBG are analyzed and compared. Finally, the theoretical analysis results are verified by experimental results. There is a good correspondence between the calculated values and experimental results.