Design And Research Of Fiber Bragg Grating Pressure Sensor

In underground engineering construction, real-time monitoring and prediction of geological hazards has become an urgent technological problem. However, the development of fiber grating sensing technology provides a feasible way to solve the problem. Although the fiber grating is small, light and flexible, etc, it also has the disadvantage of not small bending angle, structurally weak and easily broken, high accuracy for paste technology. So it is a challenging work to design a micro fiber grating pressure sensor which can be put into a small space or be embedded.In this thesis, a micro fiber grating pressure sensor is designed based on the FBG. The main work is following:(1) The research background and the development status of FBG pressure sensor are summarized.(2) Theoretical study on FBG pressure sensor model and a systematic theoretical study on its stress-temperature cross sensitivity are presented.(3) A micro fiber grating pressure sensor structure is designed and proposed, and the theoretical basis of its design is discussed in detail.(4) An experimental system is set up and the sensor is studied experimentally.(5) Micro fiber grating pressure sensor, with the minimum diameter 3cm, the maximum range for 15Mp, and the accuracy 1.271nm/MPa, can be used to measure solid pressure, gas pressure and liquid pressure.(6) A sensor network demodulation system with fast modem speed and high accuracy is designed...