Evolution of Advanced Transit Signal Priority with Gap-Based Signal Recovery Strategy

Transit Signal Priority (TSP) systems are implemented with the goal of reducing travel times for bus passengers and ensuring that buses adhere to schedules. TSP systems encounter trouble when there are multiple bus requests, heavy traffic conditions on cross-streets, or uncertain bus arrival times. In this study, existing logic concepts for TSP strategies will be modified by assuming access to video detection technologies to accurately provide bus and vehicle locations. The effect of these modifications are examined by testing different scenarios in CORSIM on parts of the Austin, Texas downtown network during peak hours. Along with the “Base” scenario, other scenarios are designed to test variations of (1) whether cross-streets are compensated for lost green time and (2) what sort of red truncation logic is used – traditional logic or logic that relies on video technology to gauge traffic conditions. Simulations will include bus occupancy levels to show the effect of switching between commute modes.