Research On Welding Expert System And Its Real-time Control

Along with the high speed development of the world welding, the welding procedure expert system has been applied widely because its low cost and high efficiency are recognized as more and more important. Especially, the ability of real-time dynamic data acquisition, data inference and data transmission are required in the welding procedure expert system in order to keep up with the step of the data change in the industrial production. Based on this trend, and combined with common principles and methods, the welding procedure expert system has been developed in this paper based on database. Correspondingly, the real-time data communication has been researched in the system.Firstly, production rules have been adopted as expression of knowledge combining characteristics of welding process. Predicate logic has been adopted as expression of basic facts and concepts, using prevalent GUI tool—Visual C++6.0, MFC DAO technology and ACCESS database. The management of knowledge and basic facts have been realized by using database technology through knowledge database management module and basic facts management module. In the guidance of the system, machine learning could be finished through adding the new rules to the database. Then, analyzing the affected factors of welding cost, the single welding line's cost could be calculated according to the cost formulas. Finally, the welding reasoning data could be sent to the single chip microcomputer, and the system could receive the feedback data from single chip microcomputer correctly. The reasoning results could be outputted through using the PCL-818HD data acquisition card which was produced by Chinese Corporation. The test results of system showed that the welding process results were correct, which were made by expert system according to the conditions of CO₂ gas arc metal welding and flat welding when material was mild steel. The welding cost of single welding line could be obtained. The data communication between the single chip microcomputer and the expert system was right. These works were the foundations of the communication between the welding procedure expert system and the welding machines. They were also the foundations of the real-time welding control in using industrial control computer.