Towards a global approach for the design of EC imaging systems

Eddy current (EC) non-destructive evaluation (NDE) techniques are widely used for the inspection of electrically conductive structures, since they are sensitive, easy to implement, robust and moreover non-polluting. For these reasons, they are likely to become more and more popular within the next years. However, raw EC signals are generally not sufficient to build a quantitative diagnosis of the inspected structure, mainly because of the incompleteness of the collected EC data and the non-linear interactions between the EC and the part under inspection. To overcome these drawbacks, a quantitative EC imaging approach should be derived, which require the design and implementation of i) an instrumental EC device able to provide EC signals sensitive to the parameters of interest, ii) an accurate modeling of the induced EC/part interactions, iii) robust and efficient signal processing algorithms able to solve the inverse problem which aims at estimating the parameters of interest starting from the collected experimental data. In this presentation, the authors propose a design approach in which the instrumental, the modeling and the inverse problem are solved in a coupled way, so as to design taylor-made EC systems dedicated to the efficient EC imaging of complex aeronautical structures.