Online Defect Detection System For High Gloss Workpiece And Its Implementation

With the rapid development of China's manufacturing industry,the output of injection molded products is increasing year by year.Injection molding products are widely used in various fields.The demand for injection molding products in food industry,pharmaceutical industry,household appliances industry,automobile industry and construction industry is increasing year by year.With the progress of society and the development of science and technology,people have higher and higher requirements for the quality and technology of injection molding products.When mass production is carried out on the industrial assembly line,it is inevitable that there will be some defects on the surface of some products.It is inefficient to detect products manually,and it also has the hidden danger of improving the false detection rate by using human eyes for a long time.Therefore,it is of great significance to detect the surface defects of injection parts intelligently.In this paper,we design intelligent light source system,pneumatic sorting system,visual inspection system and turnover system,and develop a set of online visual defect detection system applied in industrial assembly line.Aiming at the edge contour defects,surface scratches,black spots,white spots and deformation defects of the workpiece,the feature analysis,algorithm design,recognition classification and closed-loop feedback research are carried out.The testing accuracy is over 97% after running and debugging on the visual inspection system,which can reach 0.5mm scratch defect detection accuracy and 0.2mm burr and flash defect detection accuracy.The main research work of this paper is as follows1.A complete on-line detection hardware system is designed,including intelligent light source system,pneumatic sorting system and turnover system.The intelligent light source system adopts the way of low angle illumination combined with bottom side light supplement,which makes the whole illumination environment light uniform,and effectively eliminates the influence of high reflection on the visual system.The pneumatic sorting system and the turnover system respectively realize the sorting and pose adjustment of products on the production line.2.Aiming at three kinds of common defects in injection molding products,edge defects,surface texture defects and deformation defects,feature detection and calibration are carried out.By analyzing the characteristics of defects and comparing several commonly used detection algorithms,a stable and high-precision defect detection algorithm is designed: edge defect detection algorithm,surface texture defect detection algorithm and deformation defect detection algorithm,and the detection effect is good.3.According to the actual needs of industrial production,a stable,simple and easy to operate visual inspection software system is designed.Through the communication between the testing software and the injection molding machine at the manufacturing end,an information closed loop is formed in the production line,which significantly improves the quality of the product.