Frequency-dependent performance design for time-varying networked system

Much research has investigated time-delay systems; in particular, controller designs based on Lyapunov-Krasovskii-based methods have been investigated extensively. However, most previous studies do not show their methodology regarding the shaping the frequency-dependent performance. This paper proposes a control design that enables us to shape the frequency-dependent performance using a modified Lyapunov-Krasovskii-based stabilizing condition. The stabilizing controller can be obtained by solving the condition formulated in LMI. The designed controller is evaluated using numerical simulations and it is applied to the velocity control of a DC motor. Experimental results verified that the proposed controller achieved better performance with less conservativeness and that it is applicable to real plants.