Impact detection and location estimation are important components of structural health monitoring systems. This paper focuses on impact location estimation on composite structures employing a passive acoustic emission sensor array. Since composite structures are typically anisotropic, they exhibit more complex wave propagation properties than isotropic structures. The algorithm presented in this paper does not require prior knowledge of direction and location-dependent wave propagation properties within the structures. The impact location estimation problem is formulated as an unconstrained nonlinear optimization problem. Experimental results involving a sandwich composite panel indicate that the method presented in this paper is capable of accurately estimating impact locations on anisotropic composite structures and that the system is robust to temperature variations.
doi: 10.12783/SHM2015/188