|Non-contact Gap and Flush Measurement Using Monocular Structured Multi-line Light Vision for Vehicle Assembly
Thi-Trang Tran and CheolKeun Ha*
International Journal of Control, Automation, and Systems, vol. 16, no. 5, pp.2432-2445, 2018
Abstract : "The accurate fitting of various parts inspected by measuring the width of the gap between two adjacent
panels and the alignment of the two surfaces, known as flushness, is an important task in assembling vehicles. The
optimal solution requires high accuracy and fast measurement. Toward this end, we develop a vision-based noncontact
gap and flush measurement. The vision system consists of a high-resolution camera and a multi-line laser
generator. The proposed gap and flush measurement sensor projects laser lines onto the panels that are observed
by the high-resolution camera. The measurement is initiated when the operator brings the device closer to the
surface until it is within operating range. During the process, the line features are digitized by using proposed
approach, the desired calculations are made, the non-conforming images are discarded, and the remaining images
are used to perform the gap and flush measurement. The measurement system can deal with complex surface in
noisy industrial environment and achieve higher specifications compared with current gap and flush measurement
sensors. The usefulness of the proposed system has been demonstrated using real tests with accurate know-size
patterns and a real inline vehicle assembly system in Korea."
Gap and flush measurement, laser generator, monocular camera.