Research On On-line Surface Defects Inspection Of Metal Plate Based On CCD

Surface defects of metal strip are important factors which affect the quality of the metal strip. How to inspect metal strip surface defects on-line is an important means for the enterprise to control and to improve the quality of metal strip products.Fully considering the consistency of the system, we designed the on-line metal strip surface defects inspection system which includes image acquisition, real-time judge, image pre-processing, defect segmentation, feature extraction and classification. Simulated the production scene in a surface defect detection experiments, we got several achievements: taking into account the characteristics of metal strip surface defects, in laboratory conditions, designed the hardware systems of metal strip surface defects inspection system, effective simulated the production process, laid a foundation for the verification of system in production environment; studied real-time inspection method, used semi-closed image collection methods to overcome the impact on gray image brought by environment, the noise of the environment light has been controlled effectively; designed an improved smoothing filter, experimental results showed that the algorithm eliminated the noises in the images very well; for the acquisition of six typical surface defects, designed a classification algorithm based on BP neural network. Overall recognition rate reached 88.7 percent.Through this research and exploration, provide the necessary technical support for the inspection of metal strip surface defects.