Development and testing of an instrument for real-time pattern identification of cold strip surface defectsFunded under: ECSC-STEELRES 7C
The different application ranges of laser scanners and CCD line-scan cameras are discussed. The main advantage of laser scanners is the operation of several receivers looking at the strip surface from different directions, thus giving good optical defect features for identification. An electronic system has been built and tried in a recoiling line for carbody sheet for real-time classification of defects. It uses 15 optical and geometrical defect features for identification. The result is a display of the strip on a running map, the type of defect being indicated by the colour at the defect position. The optimisation of feature boundaries between different types of defect is a difficult task as it requires many defect samples with the complete variety of features of a single defect type. The feature variations of defects with frequent appearance and simple description are well known and these defects are correctly classified with a probability higher than 90%. The classification probability of less common defects is lower, since their variations are still inadequately known.
Bibliographic Reference: EUR 12666 DE (1990) 65 pp., FS, ECU 7.50
ISBN: ISBN 92-826-1324-0
Record Number: 199010862 / Last updated on: 1994-12-01
Original language: de
Available languages: de