Properties of pedestrians walking in line without density constraint

TL;DR

This study experimentally investigates pedestrian behaviors in one-dimensional traffic without density constraints, revealing stable velocities in circle formations and tendencies to maintain short headways in line flows, influenced by social pressure and individual decision-making.

Contribution

It introduces a novel experimental protocol removing density constraints, providing new insights into pedestrian behavior in line and circle formations.

Findings

Velocity in circle formations is highly stable, acting as an average of individual decisions.

Participants in line flows tend to maintain short headways despite the option for comfort.

Walking behaviors are influenced by social pressure and individual responsibility, especially in less constrained situations.

Abstract

This article deals with the experimental study of pedestrian behaviours in some situations of one-dimensional traffic. Participants were pre-organized in a line, and asked to walk either in a straight line with a fast or slow leader, or to form a circle. The originality of our experimental protocol compared to previous ones on similar situations, is to have left the condition of density free. While the observed density results from individual decisions in the line case, both density and velocity have to be collectively chosen in the case of circle formation. Our major findings are the following. In the case of circle formations, we observe that the resulting velocity is very stable among realizations, as if collective decision was playing the role of an average. For line flows with a slow leader, the same operating point close to the jamming transition is chosen as in previous experiments where it was not velocity but density that was imposed. In the less constrained line experiments, although participants could choose comfortable headways, they rather stick to short headways requiring a faster adaption - a fact that could come from a "social pressure from behind" and had previously only been observed at high densities. This could be due to the uncertainty and individual responsibility that stem in less constrained situations. Our results open new avenues for future research, as they show that the walking values preferred by humans in following tasks depend on more factors than previously considered.