L-Platooning: A Protocol for Managing a Long Platoon With DSRC

Vehicle platooning is an automated driving technology that enables a group of vehicles to travel very closely together as a single unit to improve fuel efficiency and driving safety. These advantages of platooning attract huge interests from academia and industry, especially logistics companies that can utilize the platooning technology for their heavy-duty trucks due to the huge cost savings. In this paper, we demonstrate that existing platooning solutions, however, fail to support formation of a ‘long’ platoon consisting of many vehicles especially long-body heavy-duty trucks due to the limited range of vehicle-to-vehicle communication such as DSRC and device-to-device communication for C-V2X. To address this problem, we propose L-Platooning , the first platooning protocol that enables seamless, reliable, and rapid formation of a long platoon. We introduce a novel concept called Virtual Leader that refers to a vehicle that acts as a platoon leader to extend the coverage of the original platoon leader. A virtual leader election algorithm is developed to effectively designate a virtual leader based on the novel metric called the Virtual Leader Quality Index (VLQI) which quantifies the effectiveness of a vehicle serving as a platoon leader. We also develop mechanisms for L-Platooning to support the vehicle join and leave maneuvers specifically for a long platoon. Through extensive simulations, we demonstrate that L-Platooning enables vehicles to form a long platoon effectively by allowing them to maintain the desired inter-vehicle distance accurately. We also show that L-Platooning handles seamlessly the vehicle join and leave maneuvers for a long platoon.