Prof. Helena Ramos, Invited Speaker at the 2026 FENDT Forum
Depth-aware eddy current imaging: A layered approach to subsurface nondestructive evaluation
Subsurface defect characterization using eddy current testing (ECT) remains a major challenge due to the depth-dependent attenuation of electromagnetic fields and the resulting loss of depth sensitivity in conventional inversion framework. This work proposes a novel physics-informed depth-aware inversion method for subsurface defect evaluation based on uniform eddy current excitation. Unlike conventional surface-equivalent reconstruction approaches, the proposed method introduces a depth-dependent complex attenuation factor directly into the inversion kernel, enabling layer-wise reconstruction of eddy current perturbations within the specimen. The conductive domain is discretized into multiple depth layers, and a modified kernel map is formulated using a magnetic dipole representation combined with electromagnetic diffusion physics to account for eddy current decay along the depth direction. The approach is validated through 3D finite element method (FEM) simulations, considering subsurface defects at different depths in an aluminum plate. Results demonstrate that the proposed framework captures both the lateral geometry and the vertical depth-dependent characteristics of subsurface defects. By providing a consistent relationship between reconstructed profiles and defect depth, this research offers a practical pathway for enhancing the interpretability and reliability of subsurface nondestructive evaluation.
Biography
Professor Helena Ramos is an outstanding expert in the field of non-destructive testing worldwide. With profound academic attainments and high reputation, she enjoys considerable recognition and significant academic influence in this field. From 2009 to 2020, Professor Helena Ramos served as the Vice Chair of the Scientific Committee of the Portuguese Institute of Higher Technology. From 2020 to February 2024, she held the position of Vice President (Deputy Rector) of the Portuguese Institute of Higher Technology. Currently, she is the Director of the Portuguese Telecommunications Research Institute. Professor Helena Ramos has served as a visiting researcher at Michigan State University in the United States, the Technical University of Ilmenau in Germany, Tohoku University in Japan, and Newcastle University in the United Kingdom. She has also been a visiting professor at Nanjing University of Aeronautics and Astronautics. She has been the editor-in-chief of Nondestructive Evaluation & Industrial Inspection, the deputy editor-in-chief of Measurement, the editor-in-chief of the Electromagnetic Nondestructive Evaluation special issue, the chairperson of the ENDE 2016 conference, and many other positions.
Conference Info
