Guaranteeing asymptotic zero intersampling tracking error via a discretized regulator and exponential holder for nonlinear systems

Abstract

In this paper we present the design of a robust discretized controller based in the theory of regulation for nonlinear systems. In the general command tracking and disturbance rejection problem, it is known that a sample data controller using zero order holder may only guarantee asymptotic tracking at the sampling instances. We show that by means of a so-called exponential holder, we are able to guarantee asymptotic zero output tracking error, not only in the sampling instant, but also between these instant. Some considerations on the design of exponential holders are presented. The application in simulation to some typical nonlinear systems shows the good performance of the proposed scheme.