Abstract:

This article presents the research on the development of a hybrid piezoelectric-optic fiber sensor array-based integrated structural health monitoring (SHM) system and its function evaluation on a composite unmanned aerial vehicle (UAV) wing box specimen. First, a multi-channel SHM scanning system for piezoelectronic transducer (PZT) sensor arrays is developed. This system can automatically scan up to 552 PZT actuator-sensor channels. With this PZT sensor scanning system and the fiber Bragg grating (FBG) interrogation system as hardware, an integrated system software is designed to control the damage monitoring and estimation process. These three parts form a hybrid piezoelectricoptic fiber sensor arraybased integrated SHM system. Based on this system, a SHM evaluation research is performed on a composite UAV wing box specimen with the dimension of 4000 m×1200 m×0.265 m. The SHM monitored objects are the strain distribution on the wing box skins and the joint failure which occurs during its strength experiments. Totally 34 strain points are monitored. The test proves that the system can monitor the occurrence of joint failure successfully. In addition, it can distinguish 4 kinds of joint failure grades.

Key words: structural health monitoring, PZT, fiber Bragg grating, sensor array, strain, monitoring, joint failure