Correlation Processing of Acoustic Tensometry Signals for Metal Objects

In this paper, the limits of applicability of the signal processing algorithm obtained when sounding metal objects for the purposes of acoustic tensometry are investigated. The object of the study is an algorithm for interpolating intermediate points, which is based on the use of an algorithm for finding the maximum of the correlation function. The purpose of this study is to evaluate the results obtained by varying the width of the analysis window and its position relative to the measured pulses. During the research, program studies of signals obtained on a massive sample in 6 sections and 2 positions were carried out. As part of this research, a program was developed in the MathCAD environment, which allows us to read automatically an echogram from a file with data recorded by the Prince-VIII software, select time periods from that echogram corresponding to several reflections, and calculate the correlation function for the selected signal fragments. The optimal coordinates and dimensions of the window for signal analysis are determined, and the numbers of reflections suitable for processing are highlighted. It is proposed to use the value of the pulse delay increment during the transition from the 1st to the 2nd reflection of the signal as the measured parameter.