文献类型：期刊文献

英文题名：Analytical real-time measurement of a three-dimensional weld pool surface

作者：Zhang, WeiJie[1];Wang, XueWu[2];Zhang, YuMing[1]

机构：[1]Univ Kentucky, Dept Elect Engn, Lexington, KY 40506 USA;[2]E China Univ Sci & Technol, Coll Informat Sci & Engn, Shanghai 200237, Peoples R China

年份：2013

卷号：24

期号：11

外文期刊名：MEASUREMENT SCIENCE AND TECHNOLOGY

收录：;EI(收录号：20134616962898);WOS:【SCI-EXPANDED(收录号:WOS:000325847000011)】；

基金：This work is funded by the National Science Foundation under grant CMMI-0927707.

语种：英文

外文关键词：gas tungsten arc welding (GTAW); 3D weld pool surface; reconstruction; monitoring

摘要：The ability to observe and measure weld pool surfaces in real-time is the core of the foundation for next generation intelligent welding that can partially imitate skilled welders who observe the weld pool to acquire information on the welding process. This study aims at the real-time measurement of the specular three-dimensional (3D) weld pool surface under a strong arc in gas tungsten arc welding (GTAW). An innovative vision system is utilized in this study to project a dot-matrix laser pattern on the specular weld pool surface. Its reflection from the surface is intercepted at a distance from the arc by a diffuse plane. The intercepted laser dots illuminate this plane producing an image showing the reflection pattern. The deformation of this reflection pattern from the projected pattern (e.g. the dot matrix) is used to derive the 3D shape of the reflection surface, i.e., the weld pool surface. Based on careful analysis, the underlying reconstruction problem is formulated mathematically. An analytic solution is proposed to solve this formulated problem resulting in the weld pool surface being reconstructed on average in 3.04 ms during welding experiments. A vision-based monitoring system is thus established to measure the weld pool surface in GTAW in real-time. In order to verify the effectiveness of the proposed reconstruction algorithm, first numerical simulation is conducted. The proposed algorithm is then tested on a spherical convex mirror with a priori knowledge of its geometry. The detailed analysis of the measurement error validates the accuracy of the proposed algorithm. Results from the real-time experiments verify the robustness of the proposed reconstruction algorithm.