Browse Publications Technical Papers 1999-01-3442

A Rectangular-Region, Speckle Correlation Approach for the Measurement of Interference Levels of Installed Aircraft Rivets 1999-01-3442

Experiments were conducted to determine the effectiveness of digital imaging, speckle correlation techniques for the measurement of rivet upsets. Rivets were installed in test coupons with various interference stress levels typical of current aircraft manufacturing practices. The coupons were digitally photographed before and after the installation of the rivets. These digital images were then compared using a rectangular-region correlation algorithm to determine the surface displacements caused by the rivet installation. The algorithm divides the two images into rectangular segments and then determines how far the segment of the after, or deformed, image has been displaced from the before, or undeformed, image. From this displacement data it is possible to determine the state of strain around the rivet installation, and thus the quality of the rivet installation. Experiments have shown that the algorithm is capable of determining the whole field displacement data quickly and with acceptable accuracy.


Subscribers can view annotate, and download all of SAE's content. Learn More »


Members save up to 18% off list price.
Login to see discount.
Special Offer: Download multiple Technical Papers each year? TechSelect is a cost-effective subscription option to select and download 12-100 full-text Technical Papers per year. Find more information here.