Evaluation of Route Guidance Strategies Based on Vehicle-Infrastructure Integration under Incident Conditions

Abstract

As an individual driver, having a route guidance system that provides the shortest path based on distance or an alternative path during an incident condition can be extremely useful. Even though it is more desirable to use travel times in providing route guidance, they are not readily available for every roadway segment. With the Vehicle Infrastructure Integration (VII) initiative, it is anticipated in the near future that individual vehicles equipped with VII could collect travel times and transfer such information to other vehicles and the transportation management system. Thus, travel-time information for real-time route guidance could be available through the VII. System-level potentials of the VII were explored by evaluating various route guidance strategies within the VII environment. A simulation framework was developed representing the VII-enabled virtual world, and route guidance strategies were evaluated with various factors, including market penetration of VII-equipped vehicles, congestion levels of a road network, update intervals of route guidance information, drivers’ compliance rates, and so forth. VII-based route guidance significantly reduced travel time over the no-guidance case. Among four route guidance strategies, averaged link travel time-based guidance produced the best performance. Other key findings included the following: higher market penetration generates bigger benefits, multiple operations of competing route guidance strategies did not degrade the networkwide performance, and prediction travel time-based guidance worked well for highly congested conditions.