Study On The Control Of Arc Welding Robot Welding Seam Tracking System Based On Vision

With the progress of visual technology and control technology, the intelligent degree of arc welding robot is higher and higher. But the arc welding robot space structure is complex, and more degrees of freedom of each joint, which not only requires each joint constantly adjust the deviation between welding seam and welding torch. And then to adjust the relative position of welding torch, so that the arc welding robot with automatic tracking and self-planning capacity. So it brings a great significance to study the technology of seam tracking control base on visual arc welding robot.In this paper, theoretical source and experiment data acquisition based on IRB1400 arc welding robot as the research object. Began the experiment under the support of the fund project(0728224) of Guang Xi technology department. The main research contents are as follows:(1) The seam tracking system based on visual servo control. This system is mainly composed of IRB1400 industrial robots, seam tracking rotation mechanism of block and a CCD camera.(2)The established of type IRB1400 industry robot kinematics model. Analyzed the structure of type IRB1400 industrial robots, completed IRB1400 industrial robots plus kinematics model.(3) The visual servo tracking system was studied, and guarantee the type IRB1400 industrial robot under the constant working Angle and walking Angle. Research on the relative coordinates of the position transformation relationship in welding pieces, welding torch and CCD camera.(4)Study on the control algorithm of seam tracking system and optimal control algorithm and control the visual tracking system, through the MATLAB to carry out the simulation experiment.(5) Study on the visual welding seam tracking control error. Determine the boundary conditions of application tracking system and carry out the simulation experiment.In this paper, the immune fuzzy PID algorithm is proposed in the control algorithm. Through the visual tracking system to get three points center deviation weld information as immune. And the rotating mechanism rotation Angle as antibodies, then to do the simulation examine, the simulation results show that the tracking system can quickly track weld. And the system stability and accurate performance are good, and the applicable scope is wide.At the end of the article, the tracking error of the visual tracking system was analyzed. And on the basis of the walking Angle and working Angle of the rotating mechanism. Analyzes deeply the welding torch position error, and extract the posture error of mathematical model, then use the MATLAB to simulation, the results prove that when measured pixel error is less than 80 mm, the visual system control tracking accuracy can reach the requirement of the seam tracking. And studies the self correcting error characteristic of tracking system, puts forward the welding torch pose error depends on the actual weld track and the welding torch at the end of the actual trajectory deviation between the point of view, and as the boundary conditions of seam tracking system tracking control.