Robot Welding Trajectory Planning and High Frequency Control for Curved Seams

doi:10.3969/j.issn.1004-132X.2023.14.009

Abstract

Abstract: In a robotic real-time seam tracking system, the trajectory planning and control delay affected the tracking accuracy and welding quality. To solve this problem, a piecewise real-time trajectory planning and control method for curved seams was proposed by combining B-spline curve interpolation algorithm and EGM module. Firstly, the trajectory was segmented according to the principle of optimal interpolation time. Secondly, three times non-uniform B-spline was used to interpolate each trajectory to obtain the interpolation points. Finally, the high-frequency controller of the robot was designed. The interpolation points were sent to the robot by EGM module in a cycle of 4 ms to guide the robot movements. The experimental results show that this method may complete the planning of sine curve weld and guide the robot welding in 100 ms, and the tracking errors were controlled within ±0.2 mm, which realizes the rapid trajectory planning and high-frequency control.

Key words: welding robot, trajectory planning, interpolation, B-spline curve, external guided motion(EGM)

摘要： 机器人实时焊缝跟踪系统中，轨迹规划时间及控制延迟过高会影响跟踪精度和焊接质量。针对这一问题，结合B样条曲线插补算法和外部引导运动模块，提出一种用于曲线焊缝的分段式实时轨迹规划与控制方法。首先根据插补时间最优原则将轨迹分段，然后采用三次非均匀B样条插补每段轨迹并得到插补点，最后设计了机器人高频控制器，利用外部引导运动模块以4 ms为周期将插补点依次发送给机器人，引导机器人运动。试验结果表明，该方法在100 ms内即可完成正弦曲线焊缝的规划并引导机器人焊接，跟踪精度控制在±0.2 mm以内，实现了轨迹的快速规划和高频控制。

关键词: 焊接机器人, 轨迹规划, 插补, B样条曲线, 外部引导运动

CLC Number:

TP242

WU Chaoqun, ZHAO Song, LEI Ting. Robot Welding Trajectory Planning and High Frequency Control for Curved Seams[J]. China Mechanical Engineering, 2023, 34(14): 1723-1728.

吴超群, 赵松, 雷艇. 曲线焊缝的机器人焊接轨迹规划与高频控制[J]. 中国机械工程, 2023, 34(14): 1723-1728.

References

［1］LEI Ting, RONG Youmin, WANG Hui, et al. A Review of Vision-aided Robotic Welding［J］. Computers in Industry, 2020, 123:103326.
［2］游有鹏，王珉，朱剑英. NURBS曲线高速高精度加工的插补控制［J］. 计算机辅助设计与图形学学报, 2001, 13(10):943-947.
YOU Youpeng, WANG Min, ZHU Jianying. An Interpolator for NURBS Curve Machining with High-speed and High Accuracy［J］. Journal of Computer-Aided Design & Computer Graphics, 2001, 13(10):943-947.
［3］刘杰，胡绳荪，申俊琦，等. 基于空间等距线的焊接机器人轨迹优化［J］. 焊接学报, 2017, 38(11):47-50.
LIU Jie, HU Shengsun, SHEN Junqi, et al. Trajectory Optimization of Welding Robot Based on Space Equidistant Line［J］. Transactions of the China Welding Institution, 2017, 38(11):47-50.
［4］毛征宇，刘中坚. 一种三次均匀B样条曲线的轨迹规划方法［J］. 中国机械工程, 2010, 21(21):2569-2572.
MAO Zhengyu, LIU Zhongjian. A Trajectory Planning Method for Cubic Uniform B-spline Curve［J］. China Mechanical Engineering,2010, 21(21):2569-2572.
［5］LEI Ting, HUANG Yu, SHAO Wenjun, et al. A Tactual Weld Seam Tracking Method in Super Narrow Gap of Thick Plates［J］. Robotics and Computer-integrated Manufacturing, 2020,62:101864.
［6］BALLESTER J. A Reactive Planning Framework for Dexterous Robotic Manipulation［D］. Huesca：Universitat Politècnica de Catalunya, 2019.
［7］毛翊超，陆麒. 基于视觉伺服技术的工业机器人高动态物体跟踪系统［J］. 智能科学与技术学报, 2019, 1(1):62-69.
MAO Xuchao, LU Lin. High Dynamic Object Tracking System of Industrial Robot Based on Visual Servo Technology［J］. Chinese Journal of Intelligent Science and Technology, 2019, 1(1):62-69.
［8］施法中. 计算机辅助几何设计与非均匀有理B样条［M］. 北京：高等教育出版社, 2013.
SHI Fazhong. CAGD & NURBS［M］. Beijing:Higher Education Press, 2013.
［9］董甲甲，王太勇，董靖川，等. 改进B样条曲线应用于6R机器人轨迹优化［J］. 中国机械工程, 2018, 29(2):193-200.
DONG Jiajia, WANG Taiyong, DONG Jingchuan, et al. Applications of Improved B-spline Curves to 6R Robot Trajectory Optimization［J］. China Mechanical Engineering, 2018, 29(2):193-200.
［10］贾春阳，杨岳，陈峰. 等弧长原则的NURBS曲线离散算法［J］. 计算机工程与应用, 2014, 50(3):165-167.
JIA Chunyang, YANG Yue, CHEN Feng. NURBS Curve Discrete Algorithm Based on Equal Arc Length Principle［J］. Computer Engineering and Applications, 2014, 50(3):165-167.
［11］秦霞，李德钊，邓华. 基于NURBS曲线的工业机器人位置插补算法研究［J］. 制造业自动化, 2018, 40(4):67-72.
QIN Xia, LI Dezhao, DENG Hua. Research on Position Interpolation Algorithm of Industrial Robot Based on NURBS Curves［J］ Manufacturing Automation, 2018, 40(4):67-72.
［12］JI Shijun, LEI Lianggen, ZHAO Ji, et al. An Adaptive Real-time NURBS Curve Interpolation for 4-axis Polishing Machine Tool［J］. Robotics and Computer-Integrated Manufacturing, 2021, 67:102025.
［13］WU Chaoqun, YANG Peiwen, LEI Ting, et al. A Teaching-free Welding Position Guidance Method for Fillet Weld Based on Laser Vision Sensing and EGM Technology［J］. Optik, 2022, 262:169291.

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