Abstract
In order to optimize the pose of welding torch preplanned by offline programming, a structured light-based visual servoing method is proposed. First of all, a series of phase shifting patterns are projected to acquire the so-called phase map. Afterwards, unlike usual feature extraction methods, which were based on 3-D cloud, a cylinder axis is extracted directly from the phase map to represent the connecting pipes’ cylindrical surface. Then, a visual servoing control law based on the axis combined with the seam center in phase map is proposed to optimize the pose of the welding torch. Moreover, global asymptotic stability of this method is proved. Finally, simulations and real experiments are performed to demonstrate the effectiveness and robustness of this method. Results show this method can improve the mean error of deviated distance and angle of offline programming by 73.5% and 82.5%, respectively.
Highlights
Pipe welding is one of the most reliable and prevalent methods for pipe connection [1]
We developed a structured light-based visual servoing method to optimize the pose of the welding torch at preplanned path points for pipe welding
A low-dimensional cylindrical axis is directly extracted from the phase map to represent the cylindrical surface, and the seam center is extracted to represent the axial position of the weld seam, expediting control
Summary
Pipe welding is one of the most reliable and prevalent methods for pipe connection [1]. Compared with manual pipe welding, automatic pipe welding has been increasingly used because of its high safety, quality, productivity and low cost [2]–[4]. In automatic pipe welding techniques, carriage and band system-based mechanized gas metal arc welding (GMAW) is dominant, which ensures the welding quality by laying a band on the pipe surface so that the welding carriage that holds the welding torch can rotate around the pipe [2]. To promote productivity and reliability, a dual-tandem welding process was designed, consisting of two welding torches, with each torch having two wires, and a seam tracking algorithm was proposed based on an arc sensor [3]. A five-axis welding manipulator for GMAW of steel pipe was designed, and seam tracking and weld pool control based on a vision sensor was realized [4]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
