The Research On Teaching System And Seam Tracking System Of Group Welding Arm-and-hand

In the robots machining unit, because of the diversity and complexity of the welding parts, the arc welding robot can't weld the complicated part independently, this makes it necessary to have a teaching system that has teaching function. While in the actual welding process ,as the moving track's the fluctuating of welding torch or part, welding distortion and disturbing etc, even if the track of weld joint have been taught, the instance that welding arc departures from the track of weld joint appears. In order to realize welding automation and improve welding quality, the weld joint tracking system is needed. So the teaching system is the important composed part of robot, while the weld joint tracking system is the important content.On the base of analyzing the arm-and-hand system's actuality, this thesis dicusses the design process of the arm-and-hand system's teaching system, which is a system based on singlechip. It has the function of key-press, display and communication. Welding experiment results that the teaching system is safe and reliable and the man-machine interface is friendly.As the welding process is a nonlinear, coupling and time-variable complicated process, it is difficult to built its mathematic model. Fuzzy control is employed to the weld joint tracking system. In CO2 gas metal arc welding, the difficulty hi seam tracking by pendular arc sensor is how to attain the tolerance signal of weld joint. As hi the arc welding process, there are many bad factors that affect the collection and process of arc sensor signal, the methods of hardware filtering, software filtering in time and space field and curve fitting are employed to process the arc sensor signals off-line. By using the current integral indifference method as seam tracking control algorithm and computing off line, the seam tolerance signals have been attained. On the basis of experiment results processed offline, A fuzzy controller and software used in real time seam tracking of vertical fillet joint is designed. The experimental result of welding vertical fillet joint at every position shows that the automatic seam tracking system is steady and the seam tracking precision is satisfied with the welding request of vertical fillet joint.