Damage detection in composites using optical fibre sensors

Optical fibre sensors (OFSs) are promising as tools for damage and structural health monitoring (SHM) of aerospace composite structures. Hence, many researchers have conceived various kinds of OFSs. First, a brief summary of OFSs used for composites is presented. Then, the authors' studies on the small-diameter fibre Bragg grating (FBG) sensors for damage monitoring and SHM of composite structures are described. The authors and Hitachi Cable, Ltd have developed a small-diameter optical fibre and its FBG sensor for embedment inside a lamina of composite laminates without strength reduction. Then, some recent results in the current Structural Integrity Diagnosis and Evaluation of Advanced Composite Structures (ACS-SIDE) project are presented on optical fibre-based SHM for some feasible applications in aerospace composite structures.