Adaptive Nonlinear Control of Uncertain Chaotic Gyros Subjected to Unknown Parameters and Disturbances

This paper addresses the chaos control of uncertain chaotic nonlinear gyros with unknown parameters. In general, the underlying class of gyros may be perturbed by external disturbances with different sources. Depending on the characteristics of uncertain parameters and disturbances, two different adaptive-based control algorithms are proposed. In the first method, an adaptive H∞ controller is designed when the external disturbances are square-integrable. The other proposed scheme is based on developing a pure adaptive controller, in which the parameters and disturbances can be time-varying with unknown bounds. In both methods, the prescribed robustness property is guaranteed and the stability analysis is presented, using the Lyapunov stability theorem. Simulation studies show that the goal of chaos control is achieved despite the system uncertainties and external disturbances.