Fiber Bragg Grating Sensing Technology Theory And Experimental Research

As one of the forefront research fields in sensor technology, fiber Bragg grating (FBG) sensor has been developed rapidly in recent years. The FBG sensor has been widely used in many fields, such as industry and agriculture, science and technology, national defense, space exploration, environment monitoring, healthcare, etc. Therefore, it is of great scientific significance and economic value to research and development advanced FBG sensors with features of high precision, wide range of measurement, perfect stability, long lifetime, low cost, easy digitization and integration.The FBG is applied to the detection of pressure and vibration in this thesis. We established a set of FBG sensor system by ourselves, made many experiments and obtained many good experiment results.In this thesis, a detailed discussion based on the coupled-wave theory was described to explain the optical characteristic and sensor principle of the fiber grating, and the characteristic and application of FBG sensor were narrated. Considered the demand of engineering measurement, we brought forward a new FBG sensor system, which has many merits such as small bulk, low wasting, high sensitivity, electromagnetism isolation, wide bandwidth, distributing measurement, etc.The FBG sensor system in this thesis is modulated by DWDM equipment, data acquired by NI PCI-6013 card, processed, analyzed and displayed by the software of LabVIEW, and the FBG vibration sensor system focused on the application in detecting the natural frequency of cantilever. The FBG vibration sensor system can measure the first four order natural frequency of the cantilever. Compared with the results gained by traditional PZT sensor as reference, the FBG vibration sensor error is less than 0.01%. Finally, the experiment results gained from the FBG sensor system and traditional PZT sensor are both validated by Finite Element Analysis (FEA) calculation.