Distributed conflict resolution for connected autonomous vehicles

Abstract

This paper proposes a novel communication-enabled distributed conflict resolution mechanism for interactions among connected autonomous vehicles (CAVs). The environments under consideration are generalized intersections where multiple incoming and outgoing lanes intersect. All vehicles close to the intersection are requested to broadcast their estimated times to occupy the conflict zones where a conflict zone is identified when the extensions of two incoming lanes intersect. The conflict resolution strategy is decoupled temporally for a vehicle. In a decision maker, the vehicle computes the desired time slot to pass the conflict zones based on the broadcasted information by solving a conflict graph locally. Then in a motion planner, the vehicle computes the desired speed profile by solving a temporal optimization problem constrained in the desired time slot. The estimated time to occupy the conflict zones given the new speed profile is then broadcasted again. It is shown theoretically that the aggregation of these local decisions solves the conflicts globally. Moreover, this mechanism increases the efficiency of autonomous vehicles, and outperforms conventional mechanisms such as traffic light or stop sign in a four-way intersection in terms of delay time and throughput as demonstrated by simulation.