Mixed output-feedback control of second-order neutral systems with time-varying state and input delays

A mixed H 2 / H ∞ output-feedback control design methodology is presented in this paper for second-order neutral linear systems with time-varying state and input delays. Delay-dependent sufficient conditions for the design of a desired control are given in terms of linear matrix inequalities (LMIs). A controller, which guarantees asymptotic stability and a mixed H 2 / H ∞ performance for the closed-loop system of the second-order neutral linear system, is then developed directly instead of coupling the model to a first-order neutral system. A Lyapunov–Krasovskii method underlies the LMI-based mixed H 2 / H ∞ output-feedback control design using some free weighting matrices. The simulation results illustrate the effectiveness of the proposed methodology.