The CARS demand-responsive traffic control system: recent improvements and experiences

CARS is a third generation traffic control system that follows a centralised approach and can operate either on isolated junctions, arterials, or networks. It does not rely on the traditional concepts of cycle, split and offset, but calculates acyclic settings. Coordination between junctions is achieved through an underlying simulation model that deals with packets of vehicles moving according to an ad-hoc packet-following model, and stopping in horizontal queues. Tests by the AIMSUN microscopic simulation have showed a sustained improvement over optimal fixed-control settings on a wide range of traffic conditions