How to deal with the complex coupling between the inputs and outputs and the various uncertainties is crucial to the control of MIMO nonlinearly parameterized systems. A dynamical signal was used to characterize the unmodeled dynamics in the system, adaptive nonlinear damping was employed to dominate the effects of unknown parameters, nonlinear uncertainties, unknown bounded disturbances, unmodeled dynamics and the coupling between the inputs and outputs. Based on the Control Lyapunov Function method, a robust adaptive controller was designed for MIMO nonlinearly parameterized systems. The proposed control scheme does not need to estimate the unknown parameters. It was proved that with the proposed scheme, all the variables in the closed loop system are bounded and the mean-square tracking error can be made arbitrarily small by choosing some design constants appropriately. Simulation results illustrated the effectiveness of the proposed control scheme.
