Application of Fiber Bragg Grating Technology in Spacecraft Structural Fault Detection

Abstract

With the prolongation of the service life of spacecraft, the structural failure of spacecraft caused by air resistance and aging poses a direct threat to the safe operation of spacecraft. The structural failure of aircraft is concerned by many researchers. Among them, the fiber Bragg grating (FBG) sensor has become a hotspot of aircraft structural fault research because of its good performance. Facing the difficulties of structural fault location of traditional spacecraft, slow data updating speed and poor transplant ability of positioning device, a structural fault angle measurement model based on FBG strain flower is constructed by combining FBG sensor with the principle of right-angle strain flower. On the problem of determining the main strain orientation, two groups of FBG strain rosette locations are selected to determine, and different groups of locations are cross-solved to obtain the original coordinates of impact. At the same time, aiming at the structural problems of four simple thin plates in the aircraft, a method of judging the structural load based on the disturbance trend is proposed. In the process of experiment, it is necessary to test the positioning accuracy of the structure obtained by the sensor and the size error of the load. In order to better simulate the real scene, a simulation platform of aircraft structure impact is built. During the testing process, it is found that the sensor detection platform proposed in this study can locate structural faults within 2.8 cm. The average time required for location judgment is about 1.7 ms, and the error of structural impact force is about 2.86 N. Through this study, a new detection method for structural fault detection of spacecraft is proposed, which can better ensure the safety of spacecraft.