Device and method for the automatic calculation of a TCG curve

A method for automatically calculating a distance - amplitude correction curve for an ultrasound-based non-destructive testing system used to determine the thickness of a component or discontinuities of its composition, the system comprising an ultrasound sensor and a reference component, the method comprising:

• acquiring “flight time / amplitude” pairs, termed acquisition points, for a large number of measurement points distributed over a surface of the reference component,
• classifying, unsupervised, the acquisition points, wherein this step comprises an automatic grouping of the acquisition points group-wise, each group corresponding to a thickness of the reference component;
• determining, for each group, a generic “flight time, amplitude” pair, and
• constructing the distance - amplitude correction curve by calculating a gain required in order for a value of an amplitude of each group to be equal to a predetermined target value, and
• furthermore comprising a step in which an iteration is carried out by decreasing or increasing a gain of each point of the distance - amplitude correction curve at each iteration until one obtains a sufficiently small variation of the amplitude of the points of the distance - amplitude correction curve between two successive iterations according to a previously chosen convergence criterion.