CCD-based method for automatic identification and trajectory planning of pipe space welds

Abstract

The invention discloses a CCD-based method and system for automatic identification and track planning of pipeline space weld seams and meets common welding robots' requirements on welding of the pipeline space weld seams. Before welding, a CCD collects weld seam images in a one-eye and two-position way, and transmits the weld seam images to a main control computer through a USB cable; the main control computer conducts three-dimensional reconstruction on the weld seam of a workpiece in three parts according to a general stereoscopic vision principle to obtain the three-dimensional coordinate information of the three parts of the weld seam, combines the three-dimensional coordinate information to obtain the complete three-dimensional coordinates of the weld seam to determine the starting point of welding and determine the pose change of a robot tool coordinate system in the welding process, and transmits the pose change to a robot control cabinet via the Ethernet to control a welding robot to perform welding. Through a vision sensing system, the method and the system provided by the invention can be adapted to welding of butting and intersection of pipelines of different diameters to conduct all-position automatic welding, and avoids the limitation that only single-path weld seams can be welded according manual teaching.

Description

Technical field: [0001] The invention relates to a welding technology for pipeline space welds based on visual sensing, in particular to a CCD-based method for automatic identification and trajectory planning of pipeline space welds, which belongs to the technical field of intelligent welding robots. Background technique: [0002] Pipe-pipe butt joint and pipe-pipe intersecting welds are common in fields such as petroleum, boilers, and metallurgical buildings. Pipe-pipe intersecting produces a relatively auxiliary space curve. When it is orthogonal, it will produce a standard saddle-shaped space curve. When it is oblique, it will be produce more complex spatial curves. Among the commonly used automatic welding machines for saddle-shaped welds with intersecting pipes on the market, the machine tool type is generally used for the welding of pipe-pipe intersecting lines with large batches and a single workpiece, and the machine tool is large in size and heavy in weight, suitabl...

AI Technical Summary

Problems solved by technology

[0004] At present, although there are many studies on the application of visual sensing to welding robots, and some applications have been obtained, and the more mature application is active vision, that is, the addition of laser or structured light, but the application of visual sensing to The research and application of pipeline welding are rare

At present, in the visible reports, in the document "Li Chi, Research on Tracking System of Pipeline Welding Robot Based on Visual Sensing [Ph. Cylindrical coordinate pipe welding robot circular welding seam tracking algorithm, but it can only track the pipe circular seam welding, and cannot be applied to welding when pipes intersect

The patent application number is 201110224808.4, titled "Robot Initial Welding Position Recognition System and Method Based on Monocular Vision Sensing", which provides a robot initial welding position recognition method based on monocular vision sensor, but the work is aimed at the workpiece The weld seam is horizontal, with a fixed orientation and a constant height relative to the visual sensor, which is not suitable for space welds when pipes intersect

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