Development of Real-time Defect Detection Algorithm for High-speed Steel Bar in Coil(BIC)

Abstract

In steel manufacturing industry, as many advanced technologies increase manufacturing speed, fast and exact products inspection gets more important. This paper deals with a real-time defect detection algorithm for high-speed steel bar in coil (BIC). To get good performance, this algorithm has to solve several difficult problems such as cylindrical shape of a BIC, influence of light, many kinds of defects. Additionally, it should process quickly the large volumes of image for real-time processing since a steel bar moves at high speed. Therefore defect detection algorithm should satisfy two conflicting requirements of reducing the processing time and improving the efficiency of defect detection. This paper proposes an effective real-time defect detection algorithm that can solve above problems. And the algorithm is implemented by a high speed image processing system and will be applied to a practical manufacturing line. Finally, the performance of the proposed algorithm is demonstrated by experiment results.

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