Cyber Traffic Light: Safe Cooperation for Autonomous Vehicles at Dynamic Intersections

Abstract

Autonomous driving systems are becoming increasingly feasible and highly expected to be the heart of intelligent transportation systems. To deploy the autonomous driving vehicles on public roads, one of the practical challenges might be safe cooperation and collaboration among multiple vehicles, in particular when conflicts arise on shared road segments, such as road intersections, merge points, construction zones, single-track lanes, and center turn lane. In the current traffic systems, human drivers navigate these regions using a combination of traffic rules, social norms, courtesy, hand signals, and common sense. In this paper, we identify and classify such Dynamic Intersections that might lead to vehicle accidents and/or deadlocks and that might appear almost anytime and anywhere on public roads. In addition, we present a cooperative dynamic intersection protocol that uses on-board perception systems and vehicular communications for peer-to-peer negotiation. Under our protocol, autonomous driving vehicles can create a vehicular communication-based traffic manager named Cyber Traffic Light when congestion arises. Cyber Traffic Light works as a self-organizing, self-planning, and self-optimizing traffic manager, and it allocates the green period for vehicles coming from the multiple directions. Finally, we showed that our decentralized protocol has much higher traffic throughput, compared to two simple protocols while guaranteeing road safety.