Quality of Service Impacts of CAV Penetration Rates on a Signalized Corridor

Connected and automated vehicles (CAV) are growing in popularity and could have potential implications on the transportation system. The effects of CAVs have yet to be fully realized because of the newness of the technology. Anticipated effects include increased capacity, faster travel time, improved level of service, increased safety, and overall effectiveness of the transportation system. The Highway Capacity Manual (HCM) published by the Transportation Research Board of the National Academies has incorporated some of these impacts by developing capacity adjustment factors (CAFs) for various scenarios for freeway segments, signalized intersections, and roundabouts. This study builds upon the HCM study of signalized intersections by analyzing the effect CAVs have on a coordinated signalized corridor. Using PTV VISTRO and PTV VISSIM software a seven-intersection corridor along Eagle Road in Boise/Meridian, Idaho was modeled and analyzed with increasing penetration rates of CAVs. Approach delay, queue length, level of service, and travel time along the corridor were studied as CAV penetration rates increased. It was found that approach delay, queue length, and level of service (LOS) improved as the number of CAVs increased. As CAVs increased from 0% to 100%, the LOS increased from an E to an A at small intersections and from a D or F to C at large intersections. The travel time from one end of the corridor to the other decreased.