title: An online GA-based output-feedback direct adaptive fuzzy-neural controller for uncertain nonlinear systems.
abstract: In this paper, we propose a novel design of a GA-based output-feedback direct adaptive fuzzy-neural controller (GODAF controller) for uncertain nonlinear dynamical systems. The weighting factors of the direct adaptive fuzzy-neural controller can successfully be tuned online via a GA approach. Because of the capability of genetic algorithms (GAs) in directed random search for global optimization, one is used to evolutionarily obtain the optimal weighting factors for the fuzzy-neural network. Specifically, we use a reduced-form genetic algorithm (RGA) to adjust the weightings of the fuzzy-neural network. In RGA, a sequential-search -based crossover point (SSCP) method determines a suitable crossover point before a single gene crossover actually takes place so that the speed of searching for an optimal weighting vector of the fuzzy-neural network can be improved. A new fitness function for online tuning the weighting vector of the fuzzy-neural controller is established by the Lyapunov design approach. A supervisory controller is incorporated into the GODAF controller to guarantee the stability of the closed-loop nonlinear system. Examples of nonlinear systems controlled by the GODAF controller are demonstrated to illustrate the effectiveness of the proposed method.
authors.affiliation: Department of Electronic Engineering, Fu-Jen Catholic University, Hsin-Chuang, 24205, Taipei, Taiwan, ROC. wayne@ee.fju.edu.tw
authors.forename: Wei-Yen
authors.initials: WY
authors.lastname: Wang
authors.forename: Chih-Yuan
authors.initials: CY
authors.lastname: Cheng
authors.forename: Yih-Guang
authors.initials: YG
authors.lastname: Leu