Non-contact Gap and Flush Measurement Using Monocular Structured Multi-line Light Vision for Vehicle Assembly

摘要

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 non-contact 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.