In engineering and control systems, the term “fuzzy” refers to concepts that are not clear, are vague, or are in a state of continuous change. This stands in stark contrast to traditional Boolean logic, which operates on a binary foundation of absolute truth (true/false, 1/0). Many real-world processes, however, cannot be neatly categorized into such discrete states.

Fuzzy Logic, first introduced by Lotfi A. Zadeh in 1965, is a methodology that addresses this ambiguity by resembling human decision-making. It is designed to manage vague and imprecise information by dealing in “degrees of truth.” Instead of a simple true or false, a fuzzy system assigns a value ranging from 0.0 (absolute falseness) to 1.0 (absolute truth), allowing for a more nuanced representation of reality. This logic is not itself “fuzzy”; rather, it is a precise mathematical framework used to describe and manage fuzziness.

The purpose of this application brief is to provide control systems engineers and technical managers with a comprehensive overview of Fuzzy Logic Control (FLC) systems. This brief analyzes the core architecture, design process, key benefits and drawbacks, and practical applications across a range of industries.