Towards damage and structural health monitoring of aerospace composite structures using optical fiber sensors

Optical fiber sensors are promising as tools for damage and structural health monitoring (SHM) of aerospace composite structures. The authors and Hitachi Cable, Ltd. have recently developed small-diameter optical fiber and its fiber Bragg grating (FBG) sensor for embedment inside a lamina of composite laminates without strength reduction. First, a brief summary is presented for some previous studies on the small-diameter FBG sensors for damage monitoring and SHM of composite structures. Then, some recent results in the current ACS-SIDE project are presented on optical fiber based SHM for some feasible applications in aerospace composite structures, which include (1) PZT/FBG hybrid sensing system for bond-line monitoring in CFRP box structures, (2) Highly reliable advanced grid structures (HRAGS), and (3) Distributed strain sensing using Brillouin optical correlation domain analysis.