Time-varying delay

Abstract

Before we complete Part I of the book, on predictor feedback for linear systems, and before we move on to delay-adaptive control in Part II, we examine a somewhat related problem of linear (time-invariant) systems with time-varying input or output delays. Predictor-based control for time-varying delays has a rather intuitive extension from the case of constant delay. The key is to calculate the state prediction over a nonconstant window, starting with the current state as an initial condition, and using past controls over a window of time of nonconstant length.