An improved discrete elliptic imaging algorithm based on guided waves for defect localisation in curved plates

Abstract

Many effective image-based algorithms are available for detecting and locating defects in flat plate-like structures. However, there are few studies on image-based algorithms for curved plate structures. An improved method is proposed in this article, which is based on the discrete elliptic imaging algorithm and the improved signal normalisation method. To verify its effectiveness, experiments using a circular array are conducted on curved plates with different degrees of bending. The experimental results show that the improved method can accurately locate defects in curved plates and, compared with the original discrete elliptic imaging algorithm, its range of error in locating a single defect is reduced from 20.2-33.3 mm to 2.7-5.1 mm.