Disturbance Attenuation of Feedforward Systems With Dynamic Uncertainty

This paper studies the disturbance attenuation problem of a class of nonlinear systems in feedforward form that is subject to both dynamic uncertainty and disturbance. When the disturbance vanishes, the equilibrium of the closed-loop system is globally asymptotically stable. Two versions of small gain theorem with restrictions are employed to establish the global attractiveness and local stability of the closed-loop system at the equilibrium respectively.