Early Gapping and Platoon Merging Strategies for Autonomous Vehicles using Local Controllers

Abstract

Autonomous vehicle merging schemes require a central control or a complex communication system between the vehicles. We suggest an alternative local traffic control method based on distance sensors and roadside units which provides the vehicles with the desired gap profile without the need for vehicle-to-vehicle communication. The gap profile aims to open gaps between the vehicles before an upcoming junction. To explore the profiles’ governing parameters, 140,000 simulation cases with varying conditions were run. Results show that, for a speed limit of 100 km/h and high inlet density (of 1–1.5 s between vehicles), the best strategy with respect to flow and merging percentage (of ~90%) is to use early gapping and platoon merging using linear profiles with long stabilization sections (>0.6 km). Moreover, the gapping process should start when the vehicle ahead attains a velocity of 75 km/h. In this way, fluent traffic can be sustained without perpetuating upstream traffic jams.