Research On Motion Control System Of Intersecting Line Welding Robot

Intersecting line weld is a very typical weld form in some industries like petroleum industry, chemical industry and boiler industry. It is very important to improve welding quality and welding efficiency of this kind of weld. As the intersecting line weld is a complex space curve, it is very hard to ensure welding efficiency and welding quality when using manual welding. As automatic welding has various advantages, people at home and abroad start to use automatic welding equipment to achieve welding process of intersecting line weld. In this paper, a set of motion control system of intersecting line welding robot is set. Based on the study of multi-pass welding of intersecting line weld, planning and adjustment of welding pass is realized. At last, the stability of this system is tested by experiments.A set of hardware system of 4-axis riding style intersecting line welding robot is set. This system includes four main parts, they are control system, motor system,welding system and data collection system. They provide hardware basis of motion of robot, welding, data collecting and other operations.A set of software system for intersecting line welding robot is programmed.According to the function of the system, the software system can be divided into five main modules,they are status monitoring module, trajectory calculation module,motion control module, parameter management module and troubleshooting module.These modules can realize various functions like motion control of intersecting line,welding parameter management and failure real-time processing.Based on the study of interpolation algorithm for intersecting line, an ideal mathematical model of intersecting line is set. Motion control of constant speed for intersecting line movement is realized. A weld arrangement policy is presented on the premise that the cross-sectional area of each weld is equal in multi-pass welding.Then trajectory planning of multi-pass intersecting line weld is realized.According to the features of intersecting line welding robot in this paper, a laser sensor system is used to calibrate the workpiece. Calculation functions of calibration parameters is deduced. Based on the study of adjustment method of intersecting line, a interpolation algorithm for intersecting line adjustment ispresented. It is called the method of single axis linear increment. The intersecting line trajectory is adjusted by using this method according to the actual working conditions. It is adapted to actual welding conditions.