Global regulation of high-order feedforward and non-feedforward systems with unknown time-varying delays in states and input

Abstract

In this paper, the global regulation problem is considered for a class of high-order nonlinear systems with unknown time-varying delays. More specifically, the considered systems consist of a chain of power integrators with high-order nonlinearity and there are unknown input and state delays. From the system structural point of view, the high-order feedforward nonlinearity is further extended to include non-feedforward terms. In our controller design, our controller is a memoryless one which does not use any past input values such that any a priori information on time-varying delays is not needed. The global regulation of the controlled system is analyzed by using the Razumikhin theorem and adding a power integrator method.