A New Approach to Practical Output Tracking Control for Switched Nonlinear Systems with Unstable Subsystems

This paper considers the practical output tracking problem for a class of switched uncertain nonlinear systems with unstable subsystems. A new approach combining the single Lyapunov function (SLF) method and a dynamic gain based strategy is first proposed. Then the dynamic controllers of individual subsystems and a proper switching law are constructed to guarantee that all the signals of the resulting closed-loop system are globally bounded while the tracking error between output and reference signal can be arbitrary small after a finite time. Finally, a numerical example is given to demonstrate the validity of the proposed control scheme.