An approach to the path planning of tube–sphereinter section welds.pdf

Robotics and Computer-Integrated Manufacturing 29 (2013) 41–48 Contents lists available at SciVerse ScienceDirect Robotics and Computer-Integrated Manufacturing journal homepage: /locate/rcim An approach to the path planning of tube–sphere intersection welds with the robot dedicated to J-groove joints Changliang Chen a,b, Shengsun Hu a,b, Donglin He c, Junqi Shen a,b,n a School of Materials Science and Engineering, Tianjin University, Tianjin 300072, China b Tianjin Key Laboratory of Advanced Joining Technology, Tianjin 300072, China c China Zhijian Publishing House, Beijing 100013, China article info Article history: Received 13 April 2012 Received in revised form 10 October 2012 Accepted 30 October 2012 Available online 21 December 2012 Keywords: Tube–sphere intersection (J-groove joints) B-spline interpolation Particle swarm Optimization (PSO) Point inversion Local modi?cation abstract In actual manufacturing process, many weldments have large dimensions and complex shapes, and they are usually assembled through a multi-pass welding process. The joints of the tube–sphere intersection (J-groove joints) are complex. This paper presents a complete solution in determining the welding paths based on a developed J-groove joint robot. Generating complex welding paths in terms of cubic B-spline curves is made easy using path control modules such as interpolation module and local modi?cation module. The point inversion module using particle swarm optimization is introduced to address the partition of path, which is required of the welding process. Experimental results show that higher ef?ciency as well as better weld quality can be achieved, indicating a promising and practical use of the robot for welding applications, which is rarely available at present. 2012 Elsevier Ltd. All rights reserved. 1. Introduction Complex intersection weld is a common and typical form of weld in large-pressure vessel and pipeline engineering. This kind of space curve weld, the welding qual