California Partners for Advanced Transportation Technology

The second phase of this project further investigates impacts to local traffic operations at intersections adjacent to signal preemption by SPRINTER commuter trains and comes up with countermeasures that not only minimize such impacts but also take into account the traffic signal coordination. An extended traffic signal optimization model has been developed to minimize overall traffic delays and the weighted width of “green band” along several coordinated traffic signals around the grade crossings. Based on the train’s movement detection at grade crossings and the waiting queue estimation at the end of the preemption operation, the optimized signal timings can quickly clear the queue and still maintain coordination along the corridor of interest. This study also recommends further consideration of countermeasures involving advanced train detections.