文摘
The control of a road network of signalised intersections is considered. Variants of a decentralised universal feedback control policy (UFC) are evaluated and compared with an open loop traffic regulator periodically distributing the same actuation duration to each stage (set of permitted movements). At the beginning of each cycle and for a particular intersection, the Max-Pressure (MP) controller selects a stage to actuate as a function of the adjacent queues to that intersection. Vehicle movements are modelled as a store and forward (SF) queuing network. A controller stabilises a demand if the mean queue length remains bounded. The current MP version requires no knowledge of the demand while estimates turn probabilities. A section near LA comprised of 16 intersections and 76 links is employed. The network performance is appraised when regular traffic conditions, congestions or unforeseen feasible demand fluctuations take place. The conducted study assesses the potential benefits of MP and confirms its adaptability. Each control strategy is evaluated in terms of queue lengths, delays, travel times etc. by discrete event simulations confirming the provided theoretical guaranteed (queue) bounds of MP.