Fuzzy logic control compared with other automatic control approaches

The authors present a comparison of fuzzy control algorithms with those of conventional control approaches (PID, optimal) in the case of a linear dynamic process control. They first give an overview of the different controllers used and examine the sensitivity of the fuzzy logic controller to design parameters. A comparative study between three types of controllers with regard to performance and robustness is then presented. It is concluded that the main interest of the fuzzy controller lies in its easy implementation. The expertise and experience of the human operator make it possible to elaborate a set of rules to control the system without requiring the computation of any mathematical model. For simple systems, a real-time adaptation is eased by using quantizations and look-up tables, which result in very short development and perfecting times. A fuzzy controlled system shows good results in terms of response time and precision. Moreover, such a controller allows a good robustness mainly with respect to modifications of process parameters as well as various disturbances on the control.<<ETX>>