Ultrasonic array technology was first introduced to engineering for NDT via the medical sector ... Drinkwater first introduced the concept of using ultrasonic arrays within wheel probes in 2002.
The multi-mode total focusing method," Ndt & E International, 2010. A. J. Hunter, B. W. Drinkwater, and P. D. Wilcox, "The Wavenumber Algorithm for Full-Matrix Imaging Using an Ultrasonic Array," Ieee ...