Experimental Study of Phase Transition in Pedestrian Flow

The transition between low and high density phases is a typical feature of systems with social interactions. This contribution focuses on simple evacuation design of one room with one entrance and one exit; four passing-through experiments were organized and evaluated by means of automatic image processing. The phase of the system, determined by travel time and occupancy, is evaluated with respect to the inflow, a controlled boundary condition. Critical values of inflow and outflow were described with respect to the transition from low density to congested state. Moreover, microscopic analysis of travel time is provided.Comment: To appear in proceedings of Pedestrian and Evacuation Dynamics 2014, Transportation Research Procedia, Elsevie

Experimental Analysis of Two-Dimensional Pedestrian Flow in front of the Bottleneck

This contribution presents experimental study of two-dimensional pedestrian flow with the aim to capture the pedestrian behaviour within the cluster formed in front of the bottleneck. Two experiments of passing through a room with one entrance and one exit were arranged according to phase transition study in Ezaki et al. (2012), the inflow rate was regulated to obtain different walking modes. By means of automatic image processing, pedestrians' paths are extracted from camera records to get actual velocity and local density. Macroscopic information is extracted by means of virtual detector and leaving times of pedestrians. The pedestrian's behaviour is evaluated by means of density and velocity. Different approaches of measurement are compared using several fundamental diagrams. Two phases of crowd behaviour have been recognized and the phase transition was described.Comment: In proceedings of Traffic and Granullar Flow 2013, Springe

Follower-Leader Concept in Microscopic Analysis of Pedestrian Movement in a Crowd

This paper presents a microscopic analysis of factors influencing pedestrian movement and interactions with their surroundings for two considered modes: independent movement influenced only by the surrounding conditions and synchronized movement based on following another pedestrian. This study analyses which of these effects prevail in different phases of the movement. The results show that the significant value of correlation between pedestrian velocity and corresponding individual density is observed mainly during approaching the crowd. Contrarily, in the segment of pedestrian trajectory which corresponds to movement inside the crowd, correlation between the velocity of a follower and a leader is more important. This confirms that the pedestrian behaviour in a crowd is a complex field

Microscopic Travel Time Analysis of Bottleneck Experiments

This contribution provides a microscopic experimental study of pedestrian motion in front of the bottleneck. Identification of individual pedestrians in conducted experiments enables to explain the high variance of travel time by heterogeneity of the crowd. Some pedestrians are able to push effectively through the crowd, some get trapped in the crowd for significantly longer time. This ability to push through the crowd is associated with the slope of individual linear model of the dependency of the travel time on the number of pedestrians in front of the bottleneck. Further detailed study of the origin of such ability is carried out by means of the route choice, i.e. strategy whether to bypass the crowd or to walk directly through it. The study has revealed that the ability to push through the crowd is a combination of aggressiveness in conflicts and willingness to overtake the crowd.Comment: To appear in Transportmetrica A: http://www.tandfonline.com/doi/abs/10.1080/23249935.2017.141942

Cellular model of pedestrian dynamics with adaptive time span

katedra matematik

Case study of phase transition in cellular models of pedestrian flow. In:

Abstract. One room with one exit and one multiple entrance is modelled using 32 different settings and modifications of floor field model. The influence of following aspects are investigated in the scope of the transition from free flow to congestion phase with respect to the inflow rate: Heterogeneity/Homogeneity; With/Without bounds; Moore/von Neumann neighbourhood; Synchronous/Asynchronous update; High/Low friction. Considering the average travel time through the room and average room occupancy the settings incorporating the bounds and synchronous update seems to match the experimental data from the qualitative point of view

Kernel Estimates as General Concept for the Measuring of Pedestrian Density

The standard definition of pedestrian density produces scattered values, hence, many approaches have been developed to improve the features of the estimated density. This paper provides a review of generally applied methods and presents a general framework based on various kernels that bring desired properties of density estimates (e.g., continuity) and incorporate ordinarily used methods. The developed kernel concept considers each pedestrian as a source of density distribution, parametrized by the kernel type (e.g., Gauss, cone) and kernel size. The quantitative parametric study performed on experimental data illustrates that parametrization brings desired features, for instance, a conic kernel with a base radius in (0.7, 1.2) m produces smooth values that retain trend features. The correspondence between kernel and non-kernel methods (namely Voronoi diagram and customized inverse distance to the nearest pedestrian) is achievable for a wide range of kernel parameter. Thereby the generality of the concept is supported.Comment: To appear in Transportmetrica A: Transport Science (submitted on May 20, 2022; revised version accepted on July 07, 2023