Beamforming of ultrasonic guided waves for defect search using chaos optimization

Abstract

In recent years, guided waves generation using an array sensor for inspection and location of defects in large structures like plates or pipes has been intensively studied. One of the areas of study is the use of beamforming algorithms to fusion the information collected with an array of sensors that can achieve the identification of an energy source or a discontinuity. To improve the identification, adaptive beamforming algorithms, time-frequency beamforming, filter design method, among others have been proposed; however, in most cases, they require an exhaustive search of the working area which can be time consuming. In this work, a beamforming algorithm based on a chaotic optimization search to improve time of detection of an acoustic source located on an aluminum thin plate is proposed. The experimental and numerical calculations show that the proposed algorithm reduces the search time considerably as compared with a standard systematic delay and sum (DAS) beamforming algorithm.