An Accelerated Post-processing Calculation Method of Curved Surface Profile Extraction Based on the Total Focusing Method of Ultrasonic Phased Array

Abstract

Surface profile extraction is a significant process for determining the ultrasonic beam propagation path based on the Fermat’s principle while applying the total focusing method (TFM) of ultrasonic phased array on a curved component immersed in water. However, TFM calculation is time consuming due to the large amounts of data post-processing. Hence, a trade-off between computation cost and precision of result image is must to be made. In this paper, an accelerated total focusing method (ATFM) was proposed to extract the surface profile of an arc-shaped component. The experimental results show that compared with TFM, ATFM could shorten the imaging time by more than 70% under various conditions of grid spacing. Meanwhile, the maximal error of extracted surface profile compared to the practical profile curve is about 0.7mm and the surface extraction errors near the central area are less than 0.1mm. It shows that the proposed ATFM can significantly improve the computation efficiency while ensuring the accuracy of surface extraction.

On Dispersion Compensation for GAW-Based Structural Health Monitoring

“…Various imaging techniques have been developed to evaluate the data often measured using piezoceramics [5][6][7][8]. Two of the best known are the synthetic aperture focusing technique (SAFT) [1,[9][10][11][12][13] and the TFM [5,[14][15][16][17]. These can be used to combine data recorded by different transmitters and receivers to produce an image of the surface being monitored.…”