Effect of Autonomous Driving on Traffic Breakdown in Mixed Traffic Flow: A Critical Mini-Review

TL;DR

This paper critically reviews how autonomous vehicles with different adaptive cruise control systems influence traffic breakdown in mixed traffic, highlighting that classical ACC can induce breakdown while TPACC does not.

Contribution

It introduces a model combining features of classical ACC and TPACC to analyze their distinct impacts on traffic stability and breakdown.

Findings

Classical ACC can initiate traffic breakdown and reduce highway capacity.

TPACC does not initiate traffic breakdown within the same parameter range.

The model shows how ACC parameters affect local speed disturbances and breakdown probability.

Abstract

A critical analysis of the effect of autonomous driving vehicles on traffic breakdown in mixed traffic flow is made. Classical adaptive cruise control (ACC) and ACC based on three-phase traffic theory (TPACC) are considered. We show that within a wide range of dynamic parameters of classical ACC, the ACC-vehicles can initiate traffic breakdown and reduce highway capacity. Contrarily, in the same range of parameters of TPACC, the TPACC-vehicles do not initiate traffic breakdown. To understand physical reasons for the effect of classical ACC- and TPACC-vehicles on traffic breakdown, we introduce a model of ACC that can be considered a combination of dynamic features of classical ACC and TPACC. With the use of this model, we find how the amplitude of a local speed disturbance caused by the ACC in a vicinity of a bottleneck and the probability of traffic breakdown depend on the dynamic parameters of the ACC.