Control Application Using Fuzzy Logic: Design of a Fuzzy Temperature Controller

The reason for using fuzzy logic in control applications stems from the idea of modeling uncertainties in the knowledge of a system’s behavior through fuzzy sets and rules that are vaguely or ambiguously specified. By defining a system’s variables as linguistic variables such that the values they can take are also linguistic terms (modeled as fuzzy sets), and by establishing the rules based on said variables, a general method can be devised to control these systems: Fuzzy Control (Babuška, 1998; Chen, 2009). Fuzzy control is a class of control methodology that utilizes fuzzy set theory (Pedrycz, 1993). The advantages of fuzzy control are twofold. First, fuzzy control offers a novel mechanism for implementing control laws that are often based on knowledge or on linguistic descriptions. Second, fuzzy control provides an alternative methodology for facilitating the design of non-linear controllers for plants that rely on generally uncertain control that is very difficult to relate to the conventional theory of non-linear control (Li & Tong, 2003; A. Sala et al., 2005).