Capacity Analysis of Intersections When CAVs Are Crossing in a Collaborative and Lane-Free Order

Abstract

Connected and autonomous vehicles (CAVs) improve the throughput of intersections by crossing in a lane-free order as compared to a signalised crossing. However, it is challenging to quantify such an improvement because the available frameworks to analyse the capacity of the conventional intersections do not apply to the lane-free ones. This paper proposes a novel framework including a measure and an algorithm to calculate the capacity of the lane-free intersections. The results show that a lane-free crossing of CAVs increases the capacity of intersections by 127% and 36% as compared to a signalised crossing of, respectively, human-driven vehicles and CAVs. The paper also provides a sensitivity analysis indicating that, in contrast to the signalised ones, the capacity of the lane-free intersections improves by an increase in the initial speed, maximum permissible speed and acceleration of vehicles.

Estimating the Impacts of AV and CAV and Technologies Transportation Systems for Medium, Long, and Buildout Transportation Planning Horizons

“…The Coexist project (Coexist1. 4,2018) classifies AVs into three categories: cautious, normal, and all-knowing, with the latter being equivalent to a level 5 CAV from the NHTSA definition. However, the technologies and algorithms used in each class differ.…”

“…Autonomous vehicles (AV) and connected autonomous vehicles (CAVs) are poised to change the way households and individuals own, drive, and operate their vehicles and how the transportation system performs and responds to traffic. Their introduction will potentially improve traffic safety [1,2], and roadway operation and capacities [3][4][5]. AVs and CAVs have the potential to increase capacity in traffic streams by reducing vehicle headway, improving reaction times and sensitivity to changing traffic conditions, and promoting a more consistent and efficient flow of traffic.…”

Lane-Free Traffic: History and State of the Art

“…The urban setting usually consists of many intersections where the management of LFT traffic vehicles is still an open topic. Some researchers have tried to answer this question with limited success [16]. Since several CAVs may cross each other at short distances at the intersections -sometimes even in opposite directions -the LFT driving simulations are useful for investigating the different types of static or dynamic traffic signs that could be installed to improve the actual and perceived safety of the overall system.…”