Title :
Spatial Correlation Coefficient Images for Ultrasonic Detection
Author :
Cepel, Raina ; Ho, K.C. ; Rinker, Brett A. ; Palmer, Donald D., Jr. ; Lerch, Terrence P. ; Neal, Steven P.
Author_Institution :
Univ. of Missouri-Columbia, Columbia
fDate :
9/1/2007 12:00:00 AM
Abstract :
In ultrasonics, image formation and detection are generally based on signal amplitude. In this paper, we introduce correlation coefficient images as a signal-amplitude independent approach for image formation. The correlation coefficients are calculated between A-scans digitized at adjacent measurement positions. In these images, defects are revealed as regions of high or low correlation relative to the background correlations associated with noise. Correlation coefficient and C-scan images are shown to demonstrate flat-bottom-hole detection in a stainless steel annular ring and crack detection in an aluminum aircraft structure.
Keywords :
acoustic correlation; aerospace materials; aluminium; crack detection; stainless steel; ultrasonic imaging; ultrasonic materials testing; Al - Element; C-scan images; aluminum aircraft structure; background correlations; correlation coefficient; crack detection; flat-bottom-hole detection; image formation; signal-amplitude independent approach; spatial correlation coefficient images; stainless steel annular ring; ultrasonic detection; Aircraft; Aluminum; Background noise; Image processing; Manufacturing; Matched filters; Position measurement; Steel; Time measurement; Ultrasonic variables measurement; Algorithms; Image Enhancement; Image Interpretation, Computer-Assisted; Imaging, Three-Dimensional; Pattern Recognition, Automated; Reproducibility of Results; Sensitivity and Specificity; Statistics as Topic; Ultrasonography;
Journal_Title :
Ultrasonics, Ferroelectrics, and Frequency Control, IEEE Transactions on
DOI :
10.1109/TUFFC.2007.468
