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Optical fiber sensor is a passive device, which has small size, light weight, performance, long-term stability, and the sensed height of insulation, and fiber-compatible, corrosion-resistant, anti-electromagnetic interference, etc. In civil engineering, aerospace, petrochemical, power, medical, industrial and other areas of the ship it has made a wide range of applications, Therefore Optical fiber sensor becomes a fast-growing field of sensor technologies.However, with the fiber grating sensing technology’s rapid development, the study of fiber Bragg grating FBG is not only limited to the axial stress analysis, and fiber Bragg grating FBG lateral force and the reverse has become the new hot spot. FBG reflection spectrum by the axial force, in the case of the same spectral type shift occurs. But when the fiber grating by the lateral forces and torsional forces, the spectral type moves will not only change shape and spectral type.In the influence of lateral force, friction coefficient of the correction factor, polarization of the spectral coefficient, Lateral force uniform reflection spectrum shift and deformation occurred, and in practice there are still noise. Only through the fiber grating spectral reconstruction to address these issues, to eliminate noise and accurately measure the parameters. A global sense of the adaptive heuristic search algorithm of genetic algorithm is a mechanism of evolution based on imitation arising from the optimization calculation, whcih quickly and accurately achieves optical spectrum reconstruction.This article mainly covers the following three parts:①According to the model theory of fiber grating, axial strain behavior of fiber Bragg grating, strain characteristics of transverse force, reversing the characteristics are carried out. And Corresponding sensor model has been Reasoned and proved. According to the distribution of transverse force grating, respectively, Uniformity of lateral force and the local force reflection spectrum in case of change of state are discussed. the characteristics extracted from the reflection spectrum reflect the external signal information, and the characteristics of information and the relation between the sensor is deeply studied.②In the case of large noise power the relevant function can effectively distinguish useful signal, which is useful to establishment of the objective function of genetic algorithm. Based on principle of genetic algorithm-based fiber Bragg grating and the theory of lateral uniform compression, a genetic algorithm method for the fiber grating sensor system is proposed, a mathematical model and the genetic algorithm with the objective function corresponding are established. The length of the population, evolution algebra, crossover rate and mutation rate values for the algorithm of choice are comprehensively discussed, and the parameters of genetic algorithm optimization are given.③Established Under different loading conditions, fiber grating systems are established, and the optimization of Fiber Bragg Grating reconstruction of the spectral type is achieved by Genetic Algorithm.
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