Fuzzy Logic with Engineering Applications, 4th Edition

11Fuzzy Control Systems

The decision to reject one paradigm is always simultaneously the decision to accept another, and the judgment leading to that decision involves the comparison of both paradigms with nature and with each other…the search for assumptions (even for non‐existent ones) can be an effective way to weaken the grip of a tradition upon the mind and to suggest the basis for a new one.

Thomas Kuhn, The Structure of Scientific Revolutions, 1962

Control applications are the kinds of problems for which fuzzy logic has had the greatest success and acclaim. Many of the consumer products that we use today involve fuzzy control. And even though fuzzy control is now a standard within industry, the teaching of this subject on academic campuses is still far from being a standard offering. But a paradigm shift is being realized in the area of fuzzy control, given its successes for some problems where classical control has not been effective or efficient. In Kuhn’s quote, such a paradigm shift can be explained. It was not long ago that fuzzy logic and fuzzy systems were the subject of ridicule and scorn in the scientific communities, but the control community moved quickly in accepting the new paradigm and its success is now manifested in the marketplace.

Control systems abound in our everyday life; perhaps we do not see them as such because some of them are larger than what a single individual can deal with, but they are ubiquitous. For example, economic systems are large, ...