Analysis of Left-Turning Vehicles at a 4-way Medium-Sized Signalized Intersection

This paper presents path geometries, velocities and accelerations of left-turning vehicles for one particular intersection layout. Video footage was taken above a typical urban intersection to record vehicles making left turns. The vehicle trajectories were analyzed to evaluate position, velocity and acceleration. In addition to recording whether vehicles stopped before making their left turns, the initial vehicle headings, vehicle types, traffic signal status, and destination lanes were tracked. For each travel direction, the path geometry data was analyzed to identify an average turning radius for the left turns and an average pull-out distance for vehicles that stopped before turning.