Advances in Manufacturing ›› 2020, Vol. 8 ›› Issue (4): 473-485.doi: 10.1007/s40436-020-00325-y

• ARTICLES • 上一篇    

Robust identification of weld seam based on region of interest operation

Ying-Zhong Tian1, Hong-Fei Liu1, Long Li1, Wen-Bin Wang2, Jie-Cai Feng1,3, Feng-Feng Xi4, Guang-Jie Yuan1   

  1. 1 School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200444, People's Republic of China;
    2 School of Mechanical and Electrical, Shenzhen Polytechnic, Shenzhen 518055, Guangdong, People's Republic of China;
    3 Shanghai Rui Rong Laser Welding Technology Co., Ltd, Shanghai 201306, People's Republic of China;
    4 Department of Mechanical, Aerospace and Industrial Engineering, Ryerson University, Toronto, Canada
  • 收稿日期:2020-03-17 修回日期:2020-06-25 发布日期:2020-12-07
  • 通讯作者: Guang-Jie Yuan E-mail:guangjie@shu.edu.cn
  • 基金资助:
    This study was supported by the Special Plan of Major Scientific Instruments and Equipment of the State (Grant No. 2018YFF01013101), the National Natural Science Foundation of China (Grant Nos. 51775322, 61704102, and 61603237), Project named “Key technology research and demonstration line construction of advanced laser intelligent manufacturing equipment” from Shanghai Lingang Area Development Administration.

Robust identification of weld seam based on region of interest operation

Ying-Zhong Tian1, Hong-Fei Liu1, Long Li1, Wen-Bin Wang2, Jie-Cai Feng1,3, Feng-Feng Xi4, Guang-Jie Yuan1   

  1. 1 School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200444, People's Republic of China;
    2 School of Mechanical and Electrical, Shenzhen Polytechnic, Shenzhen 518055, Guangdong, People's Republic of China;
    3 Shanghai Rui Rong Laser Welding Technology Co., Ltd, Shanghai 201306, People's Republic of China;
    4 Department of Mechanical, Aerospace and Industrial Engineering, Ryerson University, Toronto, Canada
  • Received:2020-03-17 Revised:2020-06-25 Published:2020-12-07
  • Contact: Guang-Jie Yuan E-mail:guangjie@shu.edu.cn
  • Supported by:
    This study was supported by the Special Plan of Major Scientific Instruments and Equipment of the State (Grant No. 2018YFF01013101), the National Natural Science Foundation of China (Grant Nos. 51775322, 61704102, and 61603237), Project named “Key technology research and demonstration line construction of advanced laser intelligent manufacturing equipment” from Shanghai Lingang Area Development Administration.

摘要: For welding path determination, the use of vision sensors is more effective compared with complex offline programming and teaching in small to medium volume production. However, interference factors such as scratches and stains on the surface of the workpiece may affect the extraction of weld information. In the obtained weld image, the weld seams have two distinct features related to the workpiece, which are continuous in a single process and separated from the workpiece’s gray value. In this paper, a novel method is proposed to identify the welding path based on the region of interest (ROI) operation, which is concentrated around the weld seam to reduce the interference of external noise. To complete the identification of the entire welding path, a novel algorithm is used to adaptively generate a dynamic ROI (DROI) and perform iterative operations. The identification accuracy of this algorithm is improved by setting the boundary conditions within the ROI. Moreover, the experimental results confirm that the coefficient factor used for determining the ROI size is a pivotal influencing factor for the robustness of the algorithm and for obtaining an optimal solution. With this algorithm, the welding path identification accuracy is within 2 pixels for three common butt weld types.

The full text can be downloaded at https://link.springer.com/article/10.1007/s40436-020-00325-y

关键词: Passive vision, Noise reduction, Welding path identification, Region of interest (ROI)

Abstract: For welding path determination, the use of vision sensors is more effective compared with complex offline programming and teaching in small to medium volume production. However, interference factors such as scratches and stains on the surface of the workpiece may affect the extraction of weld information. In the obtained weld image, the weld seams have two distinct features related to the workpiece, which are continuous in a single process and separated from the workpiece’s gray value. In this paper, a novel method is proposed to identify the welding path based on the region of interest (ROI) operation, which is concentrated around the weld seam to reduce the interference of external noise. To complete the identification of the entire welding path, a novel algorithm is used to adaptively generate a dynamic ROI (DROI) and perform iterative operations. The identification accuracy of this algorithm is improved by setting the boundary conditions within the ROI. Moreover, the experimental results confirm that the coefficient factor used for determining the ROI size is a pivotal influencing factor for the robustness of the algorithm and for obtaining an optimal solution. With this algorithm, the welding path identification accuracy is within 2 pixels for three common butt weld types.

The full text can be downloaded at https://link.springer.com/article/10.1007/s40436-020-00325-y

Key words: Passive vision, Noise reduction, Welding path identification, Region of interest (ROI)