Sensing Performance Of Fiber Grating-sma Stress Test

The fiber Bragg grating (FBG) sensor is a new kind of sensor. In addition to having the same functions as the traditional electric sensors, the FBG sensor also has some special characteristics such as distributed sensing, immune to electromagnetic interference, high precision and long-term stability. In this situation, the FBG sensor has widely applicable perspective in the field of the structure monitoring. However, most of the Fiber Bragg grating sensors researching or applying now are strain sensor or temperature sensor. The research on the FBG stress sensor which is often required in many projects is not a lot. This article was intended to Analysis the performance of the FBG-SMA composite stress sensor which used the SMA as the matrix material and based on the fiber Bragg grating sensor technology.Around the design of the sensor, the main contents are taken as follows:(1) Theory & Sensing Model of fiber gratingAt first, we discussed the research on the fiber optic sensor and analyzed the fundamental theory of FBG sensor. Also, some theoretical explanations about the main characteristics of FBG sensors in accordance with the basic principle were provided.Then, the sensing model of fiber grating designed in this paper was derived.(2) The design of the FBG-SMA stress sensorFirst, the FBG-SMA stress sensor was designed and the reasons why selecting the SMA materials were analyzed.Then, produced the FBG-SMA stress sensor with the pre-designed Method; analyzed the technology, such as the paste between the SMA and the fiber, encapsulation, in the process of produce the sensor.Finally, lab tests were made to calibrate the sensor and find the difference between the Test data and the theoretical analysis. Thereby obtained the Influence coefficient to correct the sensing model.(3) The lab tests& finite element analysisFirst, a set of stress lab tests were taken to check the work Performance of the SMA-FBG stress sensors designed in this paper, and the results show that the sensors have good performance. At the same time, a set of experimental data were gained to be compared with the results of Finite element analysis.Then, through the finite element analysis, got the theoretical results of the lab tests and then compared with the test results. Comparative analysis showed that the FBG-SMA stress sensor had good performance, and the test results dovetailed nicely with the theoretical results.(4) Summary & ImprovementSummed up the experience and the inadequacies of designing the FBG-SMA stress sensor. According to the problems during the course of experiment, this paper made some improvement to the sensor and lay the foundation for the future work.