Intelligent Transit Signal Priority

Existing transit signal priority strategies rely on either extending existing green or early return to green to accommodate buses. However, field experience has shown that buses are not always able to make the green times provided by either extended green or early return to green, causing additional delays to general vehicular traffic. This is, in part, because of inaccuracy in bus arrival time estimation due to unexpected heavy queues. In addition, it has been also reported that transit signal priority (TSP) often causes disruptions in traffic signal progression along the major corridor if improperly implemented. The main purpose of this project is to investigate the status of transit signal priority in Virginia, and to explore opportunities to improve TSP through connected vehicle technology.