Evaluation of Automatic Vehicle Specific Identification (AVSI) in a traffic signal control system

Automatic Vehicle Specific Identification (AVSI) is a generic name for advanced vehicle detection systems. By automating the identification of vehicles by sensing the presence of vehicles with roadside detection sites or readers, AVSI is assumed to provide vehicle specific information in traffic signal control systems.; In the application of AVSI to traffic signal control systems, as a vehicle passes a reader site, the reader records the arrival time and type of the detected vehicle. The reader would then send the information received to a local microprocessor-based traffic signal controller. The controller's built-in signal control logic would then use the information to adjust traffic signal timing to reflect the present traffic stream's characteristics.; The purpose of this research is to evaluate the potential benefits of AVSI at an isolated intersection. The evaluation of the applicability of AVSI at an intersection is accomplished by using a new developed microscopic simulation model. This simulation model is coded in SIMAN simulation language. For the purpose of validating the simulation model, a delay study is conducted at an actual intersection. The validation of the model has established a level of confidence in the obtained simulation results.; An important element of this simulation model is the development of a new Vehicle Specific Adaptive (VSA) traffic signal control strategy. VSA control strategy adjusts the signal timing based on AVSI traffic information, that is, it examines individual vehicle performance characteristics before extending a phase green time or implementing a new cycle split.; Using the simulation model, the incorporated VSA control strategy is tested against a pretimed control system. The simulation results indicates that through the use of AVSI traffic information, the VSA control logic can improve intersection performance by reducing vehicles stopped delay at an intersection.