Reducing inter-vehicular distances and the formation of groups of closely spaced vehicles have the potential to increase traffic flow, reduce congestion, and reduce fuel consumption. In this chapter, such vehicle platoons subject to a delaybased spacing policy are considered and the design of distributed controllers is pursued. Specifically, it is shown that the use of the delay-based spacing policy ensures that all vehicles in the platoon track the same velocity profile in the spatial domain, which offers advantages as road properties such as hills, bends, or road speed limits are specified in this domain. The proposed controller exploits delayed information about the preceding vehicle to achieve string-stable platoon behavior. In addition, a relaxation of the delay-based spacing policy is presented that exploits more information about the preceding vehicle. This extended delay-based spacing policy is shown to lead to improved platoon behavior. The results are illustrated by means of simulations.
QC 20190211