A linearized impact localization algorithm for the health monitoring of aerospace components

Literature presents a wide range of techniques and algorithms for the localization of impact source in isotropic structures. However, many of these methods involve either solving complex systems of nonlinear equations or a-priori training of the monitored structure. This is not only time consuming, but it requires high levels of computational effort that may often result in a poor estimation of the impact coordinates. This paper presents a novel structural health monitoring system for the impact localization on aluminium components. The proposed methodology, in contrast to current impact localization techniques, relies on an optimal sensor placement, which allows reducing the nonlinear system of equations to a linearized and simplified form. Two different Akaike Information Criterion (AIC) pickers are used to calculate the arrival times of the direct elastic waves originated by the impact source. To validate this methodology, experimental tests were carried out on aerospace components using four surface-bonded piezoelectric sensors. The results showed that this technique allows detecting and localizing the impact source with a high level of accuracy in any point of the structure.