Automatic Traffic Light Preemption for Intelligent Transportation Systems

The demand-supply imbalance in the transportation network over the last years has led to an increased level of traffic congestion in cities. This has directly affected the response time of emergency vehicles and has become an impediment to the fast travel of public transportation. Traffic light preemption is one of the most successful approaches that can be applied in crowded intersections to help reduce the overall travel time of specific groups of vehicles by automatically providing green light to offer clear passage. The purpose of this paper is to illustrate the details and benefits of a priority assignment traffic light algorithm based on vehicle type, intersection waiting queues length, and multi-intersection communication. Moreover, we implemented and evaluated its efficiency using the Sim2Car mobility simulator. The obtained results reveal that the travel time of emergency vehicles can be reduced with up to 20%, and the route duration of public transit vehicles can be shortened by 14%.