Indirect adaptive fuzzy backstepping control for nonlinear systems

In this paper, an indirect adaptive fuzzy backstepping control approach for a class of unknown nonlinear systems is developed. By a special design scheme, the controller singularity problems is avoided perfectly in this approach. Furthermore, the closed-loop signals are guaranteed to be semiglobally uniformly ultimately bounded and the outputs of the system are proved to be converge to a small neighborhood of the desired trajectory. The control performances of the closed-loop systems can be shaped as desired by suitably choosing the design parameters. Simulation results obtained demonstrate that effectiveness of the proposed approach.