An adaptive constrained control for a class of nonlinear systems with parametric uncertainties

In this paper, based on an asymmetric barrier Lyapunov function (ABLF) and the dynamic surface control (DSC) technique, we develop an adaptive constrained control scheme to address the constraints on the output for a class of nonlinear systems with uncertainties. The proposed controller guarantees the boundedness of output constraints and the asymptotic stability with online parameter adaption in the transient response. This method has the advantage of setting initial conditions subject to flexible constraints by using the ABLF, if compared with those obtained from quadratic Lyapunov function. Moreover, the DSC is introduced to eliminate repeated differentiation resulting from the ABLF synthesis and to construct a simple controller. Simulation results illustrate that the proposed method not only quickly estimates the unknown parameters with robustness against uncertainties but successfully ensures the output constraints never violated. Simulation results illustrate that the output constraints is satisfied through a numerical example.