A criterion for knowledge base decoupling in fuzzy-logic control systems

In a coupled rule base, more than one condition variable may link with more than one action variable within the same rule. This paper develops an analytical framework for decoupling such a rule base, with specific reference to fuzzy-logic control. The computational problem of fuzzy-logic is greatly simplified through the use of an uncoupled rule base. Conditions are derived, under which, decision making through an uncoupled rule base becomes equivalent to that through a coupled rule base. A laboratory prototype of a single-axis servo motor system which incorporates a knowledge-based tuner is employed to demonstrate the effective use of an uncoupled rule base that is equivalent to a coupled one