Wave-based impact localization on laminated composite plates using a coarse network of sensors

This article demonstrates a methodology for the detection of foreign object impact locations on laminated composite plates using a low number of sensors. The proposed approach exploits the wave-dominated transient response of the target structure and addresses the challenges induced by the non-uniform wave propagation due to the anisotropy of composite plates on the impact localization. Captured sensor signals are processed and their frequency content is identified. Semi-analytical wave dispersion models and time-domain spectral finite element impact models encompassing the effects of laminate anisotropy on wave dispersion characteristics are employed to extract the wave velocity from their frequency content. The method for localizing the impact site is formulated as an optimization problem and involves signal correlation from different sensors, refinement of the candidate locations, and finally accurate estimation of the impact site. Numerical and experimental validations of the developed method are presented for low-velocity impacts on glass/epoxy laminated plates.