Robust fuzzy control of nonlinear systems using shape-adaptive radial basis functions

Recently, various adaptive fuzzy control schemes have been proposed to deal with nonlinear systems whose dynamics are poorly understood by using the parameterized fuzzy approximators. However, most of the schemes presented so far can only tune the parameters, which appear linearly in the parameterized fuzzy approximators. The major disadvantage is that the desired approximation error may not be warranted and consequently, the control performance could be influenced. In this paper, we tune not only the linear parameters but also the parameters, which appear nonlinearly in the fuzzy approximators, to reduce the approximation error and to improve control performance. The proposed adaptive controller ensures global stability of the overall adaptive system and achieves desired tracking. (C) 2002 Elsevier Science B.V. All rights reserved.