Stable neuro-flight-controller using fully tuned radial basis function neural networks

A flight control scheme in which a radial basis function network (RBFN) aid s a conventional controller has been developed. The RBFN controller, consis ting of variable Gaussian functions, uses only online learning to represent the local inverse dynamics of the aircraft system. With a Lyapunov synthes is approach, a tuning rule for updating all of the parameters of the RBFN ( including centers, widths, as well as the weights of the output layer) is d erived, which extends Gomi and Kawato's strategy, where only the weights we re adaptable. (Gomi, H., and Kawato, M., "Neural Network Control For a Clos ed-Loop System Using Feedback-Error Learning," Neural Networks, Vol. 6, No. 7, 1993, pp. 933-946). The proposed tuning rule guarantees the convergence of the overall system and greatly improves the tracking accuracy. Simulati on studies using an F8 aircraft longitudinal model illustrate the superior performance of the proposed scheme. The simulation studies further indicate that the results can be extended to a dynamic RBFN in which the hidden neu rons can be added/pruned, thus producing a more compact network structure.