Error Feedback Output Regulation of Bounded Uniformly Continuous Signals for Infinite-Dimensional Linear Systems

In this article we present sufficient conditions for the existence of an error feedback controller which solves an output regulation problem for infinite-dimensional systems and bounded uniformly continuous reference/disturbance signals. The given sufficient conditions involve strong stability of the closed loop semigroup and solvability of two pairs of regulator equations; one for the plant and one for the error feedback controller. The proof of this sufficient condition relies on an argument originally due to Francis, in which the error feedback output regulation problem is solved as a feedforward control problem for the extended system. A delay-differential equation example is presented to illustrate the theory.