Automatic surface inspection and quality control - A survey

For automatic surface inspection of sheet steel today's most advanced image capturing and processing technologies are used. By this the customer gets on the one hand a detailed description of the surface quality of the entire coils, i.e. type, severity and number of defects, and on the other hand the relevant information for quality control in the required production steps. This paper describes the basic functions of automatic surface inspection systems and gives details about Parsytec's 100% software based solution - an automatic surface inspection system capable of detecting and classifying all relevant defects on strip steel surfaces. This does not only refer to cold rolled, but also to hot rolled steel where high strip speeds as well as high temperatures and the infra-red light of the steel surface aggravate inspection. Previously limiting factors like speed, defect size, textured surfaces, etc. do no longer influence the defect detection and classification process due to appropriate software implemented on high performance PCs in combination with new illumination technologies and high resolution CCD matrix cameras. Copyright (C) 1998 IFAC.