A New Impact Location Algorithm Based on S-Transform and Extended Kalman Filter

The acoustic emission (AE) is a powerful and potential nondestructive testing method for structural monitoring. Here, we show how investigation of AE data can be significantly improved by the use of advanced signal processing techniques. Such data are a fundamental source of information that can be used as the basis for evaluating the status of the material. In this article, we propose a new method based on the S-Transform and the extended Kalman Filter (EKF) to accurately localized acoustic emission (AE) sources. In the first step, a time–frequency analysis based on the magnitude of the Stockwell transform (S-transform) was used to determine the times of arrival of the AE signals. At the second step, an iterative method based in extended Kalman filter (EKF) was employed to solve a set of nonlinear equations in order to estimate the impact location coordinates and the wave velocity. With the proposed approach, the drawbacks of a triangulation method were overcome. Moreover, this algorithm proved to be very robust since it was able to converge from almost any guess point and required little computational time. The experimental validation shows promising results for a reliable and accuracy location of the A E sources.