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The advancing use of composites in high stake environments, particularly aerospace
industry demands strict monitoring of composite’s health over the entire period of life.
Health of composite structures could easily be affected by internal damages like
debonding or delamination that are invisible to naked eyes. These damages are normally
caused by unexpected impact incidences mid-flight or during ground handling. If these
damages are not identified timely, could lead to catastrophic failure. So, there is a need
of a system that could timely identify and locate these damages in real-time. FiberBragg Grating sensors have gained confidence with their capability of measuring strains
accurately along with their versatile and low-cost integration, particularly in
composites. In this research work, FBG sensors have been used to identify and locate
impact incidences on a composite laminate. Capability of FBG sensors of measuring
strain wave initiated by impact incidence is being investigated. In order to extract
quantitative information from strain response for impact localization, novel concepts
like Empirical Mode Decomposition (EMD) and Hilbert Huan Spectrum have been
used. Lastly, normalized values from spectrum are utilized and Artificial Neural
Network has been applied to train the system to differentiate between different damage
states. On the bases of predictions made by optimized ANN, comments on FBG sensors
reliability have been presented and prospects for future research work discussed.