Controlling Traffic without Tolls: A Non-Monetary Framework for Autonomous Intersections

TL;DR

This paper introduces a non-monetary, autonomous intersection management framework that influences routing decisions through timestamp-based scheduling, significantly improving traffic flow efficiency without tolls.

Contribution

It presents a scalable control strategy that influences routing via infrastructure-based delays, with a hierarchical architecture and proven equilibrium properties.

Findings

Reduces the efficiency gap between user and system-optimal flows by up to 71%.

Establishes existence and uniqueness of equilibrium flows in the proposed model.

Demonstrates effectiveness on the Sioux Falls network under realistic constraints.

Abstract

The increasing complexity of urban transportation systems, driven by connected and automated vehicles, calls for new modeling paradigms and scalable control strategies. We propose a non-monetary control framework that leverages autonomous intersection management to influence routing decisions without tolls. The approach uses timestamp-based scheduling adjustments at roadside units (RSUs) to introduce path-dependent delays or advancements, steering traffic toward socially efficient flows. We develop a hierarchical architecture that separates real-time intersection control from network-level coordination. The resulting model admits a congestion-game formulation with path-dependent node costs. We establish the existence and essential uniqueness of equilibrium flows, eliminating ambiguities due to multiple equilibria and enabling a scalable and tractable bilevel optimization formulation for system-level incentive design. Experiments on the Sioux Falls network show that the proposed approach reduces the efficiency gap between user equilibrium and system-optimal flows by up to 71% under realistic constraints. These results demonstrate the potential of non-monetary, infrastructure-light control for next-generation intelligent transportation and urban mobility systems.