An Orthogonal Curvature Fiber Bragg Grating Sensor Array for Shape Reconstruction

An orthogonal curvature fiber Bragg grating (FBG) sensor array is introduced, and it can detect the deformation and vibration of flexible structures such as rod, keel, etc. The sensor array composed of 20 sensors which were averagely distributed on four optical fibers was mounted on the body of cylindrical shape memory alloy(SMA) substrate with staggered orthogonal arrangement. By the method of calibration, the relation coefficient between curvature and wavelength shift was obtained and the curvature of sensor was calculated accordingly, then, the space shape was reconstructed with the help of the space curve fitting method based on curvature information of discrete points. In this paper, the operation principle, the design, packaging, calibration of FBG sensor array and the method of experiment were expounded in detail. The experiment result shows that the reconstructed spatial shape is lively, thus indicates that the relevant method and technology are feasible and practicable.