Large-scale marine pipeline initial point recognition and location method and system based on CCD

Abstract

The invention discloses a large-scale marine pipeline initial point recognition and location method and system based on CCD. The method and system comprise the following steps that: (1) the position of a welding line is preliminary located, wherein a CCD industrial digital camera collects the images of the welding line, a main control computer calculates the real-time change of line pixel deviation between the center of a welding gun and the center of the welding line, and a welding robot is located above the welding line preliminary; (2) pixel coordinates of an initial point are extracted, wherein one welding spot of positioned welding is recognized, a dislodgement machine drives a pipeline to move rotatably, images are collected in real-time, picture processing is conducted to a rectangular area-of-interest containing the welding gun, if the welding spot is detected, the dislodgement machine stops rotating, and the pixel coordinates of the barycenter of the welding spot are extracted; (3) the initial point is located, wherein the welding robot moves horizontally by a short distance in the Y direction of a basal coordinate system, the images of the welding line are collected, the pixel coordinates of the barycenter of the welding spot are extracted again, the three-dimensional coordinates of the initial point are calculated by the utilization of stereoscopic vision, and the welding robot is located to the initial point.

Description

Technical field: [0001] The invention relates to a CCD-based method and system for identifying and locating the starting point of a large ocean pipeline, which belongs to the technical field of automatic welding. Background technique: [0002] For the welding of large ocean pipelines, our country is still at the level of semi-automatic welding. In the actual welding process, due to the long length of the pipeline and the diameter of the pipeline can reach 1000mm or even larger, when working in the workshop, the positioning welding is carried out first, and the pipeline is temporarily fixed, and then the position of the welding torch is basically fixed, and the positioner The welding is completed by driving the pipeline to make a circular arc rotary motion. Since a welding point in the positioning welding is generally used as the starting point, after the pipe is clamped, the position of the welding point is not fixed each time. For rotary motion, when the operator observes...

AI Technical Summary

Problems solved by technology

[0004] At present, as a research hotspot in the field of welding, visual sensing technology has achieved some remarkable results, but it is mostly applied to some structural parts, and there are few researches and applications on the application of visual sensing to large-scale pipeline welding.

At present, in visible reports, the title is "Robot Initial Welding Position Recognition System and Method Based on Monocular Vision Sensing" (application number 201110224808.4) in order to enable the robot to accurately move to the starting point of the welding path, providing a The initial welding position recognition method of the robot based on the monocular vision sensor, but in this method, the weld seam of the workpiece to be welded is horizontal, and the height of the vision sensor is fixed, which is not suitable for the precise positioning of the starting point of large-scale pipeline welding

The document "Chen Haiyong, Fang Zaojun, Xu De, et al. Vision-based start point recognition and positioning control of thin steel plate welding robot [(Journal) Robotics], 2013, Volume 35, Issue 1, 90-97" proposed a The visual control method of starting point identification and welding torch precise centering of welding seam starting point automatically determines the circular region of interest containing welding torch feature points, but this application is aimed at thin steel plate welding and is not suitable for large pipe welding

Images