Visual inspection of weld surface quality

Issue title: Special Section: Intelligent Algorithms for Complex Information Services - Recent Advances and Future Trends

Guest editors: Andino Maseleno, Xiaohui Yuan and Valentina E. Balas

Article type: Research Article

Authors: Li, Yan^a | Hu, Miao^b | Wang, Taiyong^{c; *}

Affiliations: [a] Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education, Tianjin University, Tianjin, China | [b] Lingyun Industrial Corporation Limited Research and Development Center, Zhuozhou, China | [c] Tianjin Engineering Research of CNC Technology, Tianjin University, Tianjin, China

Correspondence: [*] Corresponding author. Taiyong Wang, Tianjin Engineering Research of CNC Technology, Tianjin University, Tianjin, 300072, China. E-mail: tywang@tju.edu.cn.

Abstract: Welding is an important method for modern material processing. In actual processing, due to the influence of processing accuracy and welding thermal deformation, various defects often appear in the appearance of the weld. At present, visual inspection is mainly used for the appearance inspection of welds. The detection of weld defects mainly depends on the work experience of the staff. Based on the above background, the purpose of this article is to visually inspect the weld surface quality. This article uses visually obtained fringe images of weld contours as information sources to explore a visual-based weld appearance detection algorithm, including the measurement of weld formation dimensions and the detection of weld appearance defects. This algorithm overcomes manual measurements of the misjudgments and omissions caused by eye fatigue and experience differences. It improves the efficiency and accuracy of welding appearance inspection, and meets the needs of automation and intelligence of the entire welding process. In this paper, a subpixel stripe centerline extraction algorithm based on the combination of the Hessian matrix method and the center of gravity method is used; to further improve the accuracy of the extraction of the centerline of the weld seam, this article also performs the work of removing the wrong points and the compensation of the broken seam. Obtain a fringe centerline with better connectivity. Comparing the extraction algorithms of each centerline, the centerline obtained by this method has high accuracy, less time-consuming and high stability. It laid the foundation for the subsequent inspection of weld appearance. Through the training of the model, the accurate classification and recognition of surface defects of tube and plate welds have been achieved. The experimental results show that the improved vision-based welding surface defect recognition and classification proposed in this paper has better performance and accuracy. Up to 96.34%.

Keywords: Weld quality inspection, machine vision, weld forming size, surface reconstruction, visual inspection

DOI: 10.3233/JIFS-179993

Journal: Journal of Intelligent & Fuzzy Systems, vol. 39, no. 4, pp. 5075-5084, 2020