Mechanical restriction versus human overreaction triggering congested traffic states

TL;DR

This paper introduces a cellular automaton traffic model that incorporates mechanical vehicle restrictions and human overreaction, successfully reproducing key empirical traffic phenomena like synchronized flow and platoon effects.

Contribution

It presents a novel CA traffic model combining mechanical restrictions with human overreaction, enhancing the understanding of free flow phenomena.

Findings

Model reproduces synchronized flow and pinch effect

Captures time-headway distribution in free flow

Suggests platoon formation explains free flow phenomena

Abstract

A new cellular automaton (CA) traffic model is presented. The focus is on mechanical restrictions of vehicles realized by limited acceleration and deceleration capabilities. These features are incorporated into the model in order to construct the condition of collision-free movement. The strict collision-free criterion imposed by the mechanical restrictions is softened in certain traffic situations, reflecting human overreaction. It is shown that the present model reliably reproduces most empirical findings including synchronized flow, the so-called {\it pinch effect}, and the time-headway distribution of free flow. The findings suggest that many free flow phenomena can be attributed to the platoon formation of vehicles ({\it platoon effect})