Удосконалення системи вихрострумового контролю та моделі аналізу сигналу відгуку для збільшення інформативності при ідентифікації металів

The paper examines the results of metal object identification using an eddy current dynamic control system based on the amplitude-phase method of processing the response from the object under study. The article proposes an improved signal-response model of the eddy current dynamic control system. The considered aspects of the implementation of the dynamic control process allowed us to improve the previously proposed analytical model of signal-response description, thanks to which it now takes into account the electrical and magnetic characteristics of metals analytically, and not by approximating the shape of the response signal as in the previous model. The work emphasizes that an important variable of the model is the speed of passing a metal object over the antenna plane. The speed affects the shape of the signal-response and the information coefficients calculated later. A study was conducted to determine the optimal speed of passing a metal object over the antenna surface, which corresponds to the range of linear speeds of 4...6 m/s. Metal identification using several different rotation frequencies is better and more accurate, as it allows for a more informative characterization of an unknown new sample and to determine which ones it is most similar to. The investigation for determine the optimal rotation frequency of metal objects above the antenna plane allowed to increase the informativeness of the system, as evidenced by the increase in the correlation difference when distinguishing metals, for example, copper and other metals, from 10-15% to 20-25%, for example, tantalum from 8-12% to 15-20%, and cobalt from 10-12% to 20%.