Time-optimal control of time-lag systems with time-lag controls

Abstract This paper considers the time-optimal control problem for a class of time-lag systems in which the time-lag is the control variable. It is shown that under certain conditions, the attainable set at any time t is convex, compact, and varies continuously with t. Using this result, a necessary condition for the time-optimal controls in the form of a maximum principle is derived. A simple example and other related problems are also discussed.