Multi-Vehicle Trajectory Planning at V2I-enabled Intersections based on Correlated Equilibrium

TL;DR

This paper introduces a V2I-enabled intersection trajectory planning method based on Correlated Equilibrium, enhancing safety and efficiency by coordinating vehicle trajectories through a centralized recommendation system.

Contribution

It proposes a novel CE-based framework for multi-vehicle trajectory planning at intersections, ensuring safe, consensual, and rational vehicle behaviors with V2I communication.

Findings

Effective in balancing safety and traffic flow

Reduces collision risk compared to NE-based methods

Validated through experiments with multiple vehicles

Abstract

Generating trajectories that ensure both vehicle safety and improve traffic efficiency remains a challenging task at intersections. Many existing works utilize Nash equilibrium (NE) for the trajectory planning at intersections. However, NE-based planning can hardly guarantee that all vehicles are in the same equilibrium, leading to a risk of collision. In this work, we propose a framework for trajectory planning based on Correlated Equilibrium (CE) when V2I communication is also enabled. The recommendation with CE allows all vehicles to reach a safe and consensual equilibrium and meanwhile keeps the rationality as NE-based methods that no vehicle has the incentive to deviate. The Intersection Manager (IM) first collects the trajectory library and the personal preference probabilities over the library from each vehicle in a low-resolution spatial-temporal grid map. Then, the IM optimizes the recommendation probability distribution for each vehicle's trajectory by minimizing overall collision probability under the CE constraint. Finally, each vehicle samples a trajectory of the low-resolution map to construct a safety corridor and derive a smooth trajectory with a local refinement optimization. We conduct comparative experiments at a crossroad intersection involving two and four vehicles, validating the effectiveness of our method in balancing vehicle safety and traffic efficiency.