The applicability of classical control methods has been demonstrated in many practical control problems in industry. It is shown, however, that still unanswered questions remain, which can probably be solved with the fuzzy system approach. Modern production methods and modern production units require increased flexibility. This results in highly nonlinear system behavior of partly unknown systems. Advanced control methods developed by system and control theorists are only partly able to satisfy the demands. It is in this area that fuzzy modeling and control methods can play an important role, because available qualitative operator and design knowledge can easily be implemented. In the paper, the possible role of fuzzy systems in low level control and in more advanced control is indicated. The introduction of fuzzy methods has been a controversial subject and has resulted in many misunderstandings. The paper tries to clarify this situation and to emphasize the possible cooperation between the various players in the game: conventional control theory, fuzzy control, the AI community, and last but not least the end users. (C) 1997 Elsevier Science B.V.
