Research On Detection Of Surface Defects In Internal Bushing Of Air Conditioning Pipe Joint Based On Image Processing

With the advance of ‘Industry 4.0' and the gradual development of automatic inspection,quality requirements for products surface quality is constantly improving,and traditional manual detection methods cannot satisfy the requirement of modern production.Meanwhile,the automatic inspection technology based on machine vision has been widely applied in the field of industrial production detection.Machine vision detection technology has gradually took the place of traditional detection methods in small parts surface defect detection with its advantages of precise,fast and stable.In this paper,an image processing method is proposed to realize the surface detection of internal bushing of air conditiong pipe joint.The main contents of the study are as follows:(1)Surface detection of internal bushing of air conditiong pipe joint is analyzed,and the principle of surface defection and overall scheme design of detection system are proposed to build visual inspection platform and collect the original images.(2)Combining machine vision with image processing technology,the original images are preprocessed and noise is eliminated by image filtering.The edges are extracted through the improved Canny operator,and the contour size is measured with the fitting of inner and outer diameter by the Hough circle detection algorithm and pixel size calibration.(3)Two common types of defects on the internal bushing of air conditiong pipe joint are studied.Besides,targeted lighting design for different defect area and segmentation methods for different types of defects are carried out,and the characteristic information of the detected defect can be emphasized in the best way with mathematical morphology processing method based on segmentation and GrabCut segmentation algorithm.(4)According to the curved surface feature of surfaces under detection,a surface model is presented to realize the estabilishing of relationship between image plane and actual object surface.Furthermore,camera calibration is adoped to realize the transformation of image plane to object surface.In this paper,a research on detection of surface defects in internal bushing of air conditioning pipe joint based on the technologies of machine vision and image processing is presented.And the design of defferent defect information detection scheme is implemented to realize non-contact automatic detection with accurate detection result.The detection efficiency and accuracy are significantly higher than traditional manual detection methods.The presented detection method can realize the improvement of precision,speed and reliability of industrial production.Furthermore,i t is of certain significance to the research of theoretical value and practical application.