The outline of fuzzy control algorithms and its industrial applications are surveyed. Fuzzy theory was proposed by Prof. L.A. Zadeh (U.C. Berkeley) in 1965. In early 10 years a lot of teoretical papers have been published. In 1974 a guide line of fuzzy industrial applications was indicated by Prof. E.H. Mamdani (London Univ.). He applied the fuzzy inference algorithm to automatic steam engine control problem. From that time a number of R & D works have been done in the field of fuzzy control. Finally in 1980 a fuzzy controlled cement kiln was realized by F.L. Smidth Ltd. Then many Japanese industries took part in this field. At present more than 100 industrial fuzzy applications are reported. Fundamental idea in such applications lies on so called min max composition center of gravity method. This fuzzy control algorithm is also mentioned with the fundamental notion of fuzzy set theory.
