管道全位置焊缝三维测量研究  

Research on 3D Measurement of All-position Welding Seam of Pipeline

作　　者：胡曦 余震[1] 刘海生 Hu Xi;Yu Zhen;Liu Haisheng(School of Machinery and Automation,Wuhan University of Science and Technology;School of Mechanical Engineering,Hubei University of Arts and Science)

机构地区：[1]武汉科技大学机械自动化学院 [2]湖北文理学院机械工程学院

出　　处：《石油机械》2021年第9期129-136,共8页China Petroleum Machinery

基　　金：湖北文理学院年度学科开放基金项目“焊缝外观质量视觉检测方法研究”(XK2019003)。

摘　　要：为实现焊缝尺寸在线测量,提出一种基于双目视觉的管道全位置焊缝三维测量方法。先采用平面模板法对所设计的双目系统进行标定,然后采集焊缝图像并进行极线校正。通过构建与像素点灰度值、灰度值梯度以及邻域的平滑性相关的能量代价函数进行立体匹配,获得连续平滑的焊缝视差图,结合三角测量法计算三维坐标重构出焊缝点云。定义了焊缝宽度、余高计算方法,针对管道全位置焊缝,将其分为8个区间,分别重构点云并提取特征点坐标,三维测量各区间焊缝余高和宽度,然后结合贪婪算法重构出的焊缝三维模型进行分析。研究结果表明,管道全位置焊缝三维测量方法的测量误差在0.2 mm以内,且测得平焊缝余高较小,立焊缝宽度较窄,而仰焊缝焊道较凸,余高较大,能实现焊缝尺寸的在线测量。研究结果可为管道焊缝的全位置测量提供一定的指导。In order to realize on-line measurement of weld size,a 3D measurement method for welding seam of pipeline based on binocular vision was presented.Firstly,the plane template method was used to calibrate the designed binocular system,and then,the weld image was collected and the polar correction was carried out.By means of constructing the energy cost function related to pixel gray value,gray value gradient and neighborhood smoothness for stereo matching,the continuous and smooth weld parallax map was obtained,and combined with the triangulation method,the 3D coordinates were calculated to reconstruct the weld point cloud.The calculation method of weld width and reinforcement was defined;the all-position welding seam of pipeline was divided into 8 areas to reconstruct point cloud respectively and extract the coordinates of the characteristic points;3D measurement was carried out for the weld reinforcement and width of the areas,and finally,combined with the greedy algorithm,the 3D model of welding seam was reconstructed to conduct analysis.The research results show that the measurement error of the 3D measurement method for the all-position welding seam of pipeline is within 0.2 mm,the measured flat weld reinforcement is small,the measured vertical weld width is narrow,the overhead weld bead is convex and its reinforcement is large,so the 3D measurement method can realize the on-line measurement of the weld size.The research results provide certain guidance for the all-position measurement of the pipeline weld.

关 键 词：双目视觉 视差图 焊缝点云 全位置焊缝 三维测量 

分 类 号：TE832[石油与天然气工程—油气储运工程]