Bicycle Detection and Operational Concept at Signalized Intersections

In support of efforts to improve traffic signal timing to accommodate the needs of bicyclists, observations have been made of the timing of bicyclists’ intersection crossing maneuvers. Video recordings were made of bicyclists’ crossings and the video images were processed to extract the bicyclists’ trajectories. These were synchronized with video images of the traffic signals so that the timing of the bicyclists’ maneuvers could be determined relative to the signal phase. The processed data have yielded cumulative distributions of the crossing speeds of bicyclists who did not have to stop at the intersection and the start-up times and final crossing speeds of the bicyclists who had to cross from a standing start. A unique feature of these data is the timing information relative to the traffic signal, which will be essential for determining signal phase durations. The sensitivity of the bicycling performance measures to differences between the data collection sites indicates the desirability of collecting such data under a wider range of conditions.