Reaserch On Rail Type Pipe Welding Robot Based On Expert System

A kind of pipe welding robot based on expert system is researched in both ways of mechanical construction and controlling system in this paper. Miniaturization and modularization of mechanical construction is realized. At the same time, the controlling system that consists of up-controller and down-controller is designed.The basic structure of expert system, the means to express knowledge, the reasoning mode and the building strategy is studied, and the pipe welding process parameters of up-controller expert system is established. The system has provided a simple way to manage knowledge bases which users can conti(?)ously update to meet new welding requirements.PLC is the main controller of down-controller system. An absolute encoded position sensor and laser seam track sensor is adopted, so it can control the torch moving in three directions, and can remember welding parameters. To complete the setting of welding process parameter when welding vehicle in different traveling position, it is a good method to divide semi-circumference of whole welding pass into four large sections, the welding parameters in each small section was calculated out with a interpolation, for the transition between small sections, using three times of interpolation to calculate every speeds in all points, so the transition of parameters at all different welding position were smoothly. The seam tracking is accurately and quickly. Data and order are transferred through serial communication between up-controller and down-controller. The expert system of welding robot based on the Windows operating system is conveniently and simply in using.The experiment shows that this system is reliable and convenient. It can improve the pipelines welding quality and production efficiency, and it has widely application prospect.