Output-feedback control of a class of high-order nonlinear systems

This paper considers a concrete example, and designs an improved output-feedback controller from the viewpoint of reducing the control effort at premise of maintaining the desired control performance (e.g., asymptotical stability). By introducing a new rescaling transformation, adopting an effective reduced-order observer, and choosing ingenious Lyapunov function and appropriate design parameters, the output-feedback controller guarantees the globally asymptotical stability of the closed-loop system. Simultaneously, from both the theoretical analysis and a concrete example, the smaller critical values for gain parameter and rescaling transformation parameter are obtained to reduce effectively the control effort and the rate of change of controller than the design of the related papers. At last, simulations are given to compare the control effort of two control schemes.