Research On Weld Identification And Tracking Control Method Of Argon Arc Welding

As an important processing method,welding is widely used in all walks of life.The appearance of unmanned automatic welding technology not only greatly improves the production efficiency of welding products,but also improves the quality of welding products.Argon arc welding is used in the welding of many precision parts.The welding process is a complex process.In order to ensure the welding quality,it is necessary to correct the relative position between the welding gun and the weld in real time.However,there is no such product in the market at present.Therefore,it is of great practical significance to study a control method that can automatically adjust the relative position between the argon arc welding gun and the weld.According to the parameters of the argon arc welding manipulator and the hardware structure of the 6-DOF manipulator,this paper analyzes and explains the changes of the 6-DOF manipulator trajectory,and establishes the motion model in the software.The best sampling distance of image sensor with different pixel resolution is defined,the difference of weld pool forming under different inclination angle of welding gun is analyzed,and the importance of offset correction in the welding process is explained.In view of the bad image sampling environment during argon arc welding,firstly,the gray image of the weld is enhanced and de-noising.Secondly,the best threshold of the binary image of the weld is obtained based on the maximum difference between classes method,and the image is segmented.After edge detection and traversal,the weld parameters are obtained,and the weld centerline is extracted as the trajectory of the welding gun,so as to achieve the purpose of weld tracking.After analyzing the trajectory of the welding torch,the kinematic models of the welding torch,the base and the image sensor are established.The real error of welding torch and weld seam is obtained through calculation,and the horizontal direction is adjusted according to the slope deviation obtained by real-time transmission.According to the comparison between the visual field width mark on the surface of the weldment and the visual field width ruler built in the camera,the height of the welding gun can be calculated through the visual field width difference,and the deviation value in the vertical height direction can be obtained.The relative position of the welding gun and the weld can be adjusted to achieve the purpose of automatic deviation correction.Through the simple test of the automatic welding tracking control method of argon arc welding studied in this paper,the application effect is good,which can reduce the defective products and improve the processing quality.