On the Capacity of Future Lane-Free Urban Infrastructure

TL;DR

This paper investigates the potential capacity and efficiency of future lane-free autonomous urban traffic, demonstrating higher capacity than lane-based systems and introducing a novel intersection management approach called OptWULF.

Contribution

It provides analytical and simulation evidence that lane-free traffic increases capacity and introduces OptWULF, a new automated intersection management method utilizing multi-agent conflict-based search.

Findings

Lane-free traffic offers higher capacity than lane-based traffic.

OptWULF achieves efficient utilization of street and intersection space.

OptWULF handles asymmetric demand without capacity loss.

Abstract

In this paper, the potential capacity and spatial efficiency of future autonomous lane-free traffic in urban environments are explored using a combination of analytical and simulation-based approaches. For lane-free roadways, a simple analytical approach is employed, which shows not only that lane-free traffic offers a higher capacity than lane-based traffic for the same street width, but also that the relationship between capacity and street width is continuous under lane-free traffic. To test the potential capacity and properties of lane-free signal-free intersections (automated intersection management), two approaches were simulated and compared, including a novel approach which we call OptWULF. This approach uses a multi-agent conflict-based search approach with a low-level planner that uses a combination of optimization and simple window-based reservation. With these simulations, we confirm the continuous relationship between capacity and street width for intersection scenarios. We also show that OptWULF results in an even utilization of the entire drivable area of the street and intersection area. Furthermore, we show that OptWULF is capable of handling asymmetric demand patterns without any substantial loss in capacity compared to symmetric demand patterns.