Three-dimensional defect reconstruction from MFL signals using space mapping optimization..

In this paper, we propose a new procedure to estimate the shape of the opening and the depth profile of an arbitrary three-dimentional (3-D) defect from magnetic flux leakage (MFL) measurements. We first use the Canny edge detection algorithm to estimate the shape of the depect opening. Then we use an inversion procedure based on the spave mapping (SM) methodology in order to approximate the defect depth profile efficiently. To demonstrate the accuracy of the proposed inversion technique, we reconstruct two defects of arbitrary shapes from simulated MFL signals. In both cases, the comparison of the actual and reconstructed defects validate the proposed technique.