In one-side welding with full penetration, the use of backing strips helps support molten weld metals, but increases manufacturing cycle time and cost. The backing-free welding technology is under investigation for medium-thickness structural components in the aerospace industry. Its crucial challenge is ensuring complete joint penetration and maintaining a suitable and stable backside bead width. This paper presents an innovative method of controlling weld formation based on weld-face vision sensing in arc welding. A standard laser triangulation setup is used to obtain images of weld pool, and a new weld-face feature ‘depression degree of the weld pool’ is proposed. An image processing procedure is developed to extract the depression degree of the weld pool from images in real-time. The depression degree of the weld pool is found to correlate closely with the backside bead width, and is a better indicator of the backside bead width than the weld pool width, with a higher consistency and a smaller time lag. Employing the depression degree as a feedback signal, a backside bead width control method is developed and implemented. Welding experiments on 6-mm-thick aluminum alloy 2219 plates show that the presented method is remarkably effective in achieving full penetration and keeping backside bead width constant.

在全熔透的单面焊接中，使用背衬有助于支撑熔化的焊缝金属，但会增加制造周期时间和成本。无背衬焊接技术正在航空航天工业中用于中等厚度结构部件的研究中。其关键挑战是确保完全渗透并保持合适且稳定的背面焊缝宽度。本文提出了一种基于弧焊焊接面视觉传感控制焊缝成形的创新方法。采用标准的激光三角测量装置获取熔池图像，并提出了一种新的焊接面特征“熔池凹陷度”。开发了一种图像处理程序，以从图像中实时提取熔池的凹陷程度。发现熔池的凹陷程度与背面焊道宽度密切相关，与焊道宽度相比，背面焊道宽度是一个更好的指标，具有更高的一致性和更小的时滞性。 。 ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? ? 利用压低度作为反馈信号，开发并实现了背面焊缝宽度控制方法。6 毫米厚的 2219 铝合金板的焊接实验表明，所提出的方法在实现完全熔透和保持背面焊缝宽度恒定方面非常有效。