An Evolutionary Learning Mechanism

The design of intelligent controllers for nonlinear systems continues to be a challenging problem, particularly when the system is uncertain or the environment noisy. A nonparametric approach which has gained success is to employ a neural network to learn about the unknown plant and fuzzy inference to compensate for the uncertainty (GANFIS control). Inherent in the design of such controllers is the need to tune the weights of the GANFIS controller. Evolutionary learning has been suggested to tune the GANFIS parameters but a difficulty is selecting the parameters for tuning. Further, it is well known that proper selection of the fitness function has an important effect on system performance. In this paper, we integrate two design techniques that we have previously developed into a single generalized ANFIS controller: adaptive tuners to select critical evolutionary parameters and a predictive fitness function for measuring system performance. The adaptive tuners also employ this predictive fitness as part of selection process which is a new approach. Results show that this approach is a feasible method in designing GANFIS controllers using evolutionary tuning and predictive fitness.