Acoustic emission–based impact location estimation on composite structures

In this article, an acoustic emission–based impact location estimation algorithm is presented for use with composite structures. The algorithm is formulated as a constrained optimization problem by utilizing sensor locations and times of arrival of impact signals at the sensors. The impact locations are estimated without any information about wave propagation velocity in the structure. A modification of the algorithm to overcome difficulties produced by waveform reflections enables accurate estimation of impact locations close to the structure’s boundaries. The capability of this algorithm to accurately estimate impact locations is demonstrated numerically and experimentally. Experiments performed at different temperatures showed that the algorithm is robust to temperature changes. An automatic time-of-arrival estimation method is also presented. The performance capabilities of the method and its computational simplicity make this approach an attractive alternative to other methods available in the literature for practical structural health monitoring applications.