Advantages of Synchronizing Vehicles Intersection Access

An intersection area is a common space that must be efficiently shared over time between vehicles with conflicting trajectories from several road lanes. Numerous traffic light control (TLC) strategies have been presented to address this. The main objective is periodically switching intersection access between road lanes by permitting vehicles sequentially, parallelly, or synchronously. This work addresses which intersection access type is more efficient for throughput, travel delays, fuel consumption, and associated tailpipe emissions. We compare the performance of five state-of-the-art TLC approaches in two types of road networks. Among the five TLC approaches, three are sequential, one is parallel, and the other is synchronous. In the first road network, all four intersections are homogeneous with four legs. The second network is heterogeneous, with two intersections with four legs and the other two with three legs, i.e., T-intersections. We also consider two maximum speeds (30 and 50km/h) representing low-speed urban settings. SUMO simulation results suggest all access types have similar throughput, with a minor advantage of synchronous access (up to 3%). However, compared to the other best approaches, synchronous intersection access significantly reduces travel time loss (up to 130.5%) and fuel consumption (up to 37.2%).