Abstract: Fuzzy control is a new technology based on artificial intelligence. Compaired with traditional control mathods it appeared more useful and practical in many cases as well as in the welding process, though the analysis of its stability and precision has not been proven perfactly. In this paper some basic concepts of fuzzy control were simply introduced with the welding instance; such as fuzzy set, membership-function, fuzzy rules and inference, and the typical construction of the fuzzy controller. Then some reseaches on the application of fuzzy control to welding process and the experimental results were described. The fuzzy control of the penetration in MIC welding is an example of single-input/single-output system. It was discussed in the part of fuzzy control for seam tracking how to determine the fuzzy parameters and how to improve the property of the control system. At last CO2 welding conditions control was shown as a multi-input/multi-output fuzzy system.

Key words: Fuzzy control, Thinking logic, Welding process