Observer-based H. control for nonlinear perturbations in state and input

The paper focuses on the robust H_∞ controller design based on observer for a class of uncertain time-delay systems with non-linear perturbation in the state and control input. Under the assumption that the uncertainties are timevarying and norm-bounded, based on linear matrix inequality, by constructing Lyapunov function and choosing proper observer, we bring forward an approach for robust H_∞ controller design. This approach is proved to be able to make the closed-loop systems asymptotically stable and also guarantee the closed-loop system to meet H_∞ performance index. H_∞ controller can be obtained by solving the corresponding linear matrix inequality.