A comparison between parametric and PCA methods of dimension reduction application to an eddy current non destructive evaluation

Abstract

The remote field eddy current technique is used to inspect conductive pipes and to estimate the dimensions of grooves liable to exist in the conductive material. The problem is to calculate an estimation of groove size from observed data. A two-step inversion is proposed. The first step consists of a reduction of the observed data. For that purpose, a parametric approach and a principal component analysis approach are presented. The second step is based on a polynomial regression and a least square method is used for the two approaches described in the first step. Both approaches are finally compared in terms of precision and robustness.