  In this work, an intelligent controller is employed to the chaos control
problem in a nonlinear pendulum. The adopted approach is based on the sliding
mode control strategy and enhanced by an adaptive fuzzy algorithm to cope with
modeling inaccuracies. The convergence properties of the closed-loop system are
analytically proven using Lyapunov's direct method and Barbalat's lemma.
Numerical results are also presented in order to demonstrate the control system
performance.
