811 research outputs found
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
Effects of Boundary Conditions on Single-File Pedestrian Flow
In this paper we investigate effects of boundary conditions on one
dimensional pedestrian flow which involves purely longitudinal interactions.
Qualitatively, stop-and-go waves are observed under closed boundary condition
and dissolve when the boundary is open. To get more detailed information the
fundamental diagrams of the open and closed systems are compared using
Voronoi-based measurement method. Higher maximal specific flow is observed from
the pedestrian movement at open boundary condition
Individual Microscopic Results Of Bottleneck Experiments
This contribution provides microscopic experimental study of pedestrian
motion in front of the bottleneck, explains the high variance of individual
travel time by the statistical analysis of trajectories. The analysis shows
that this heterogeneity increases with increasing occupancy. Some participants
were able to reach lower travel time due more efficient path selection and more
aggressive behavior within the crowd. Based on this observations, linear model
predicting travel time with respect to the aggressiveness of pedestrian is
proposed.Comment: Submitted to Traffic and Granullar Flow 2015, Springe
Noise-Induced Stop-and-Go Dynamics in Pedestrian Single-file Motion
Stop-and-go waves are a common feature of vehicular traffic and have also been observed in pedestrian flows. Usually the occurrence of this self-organization phenomenon is related to an inertia mechanism. It requires fine-tuning of the parameters and is described by instability and phase transitions. Here, we present a novel explanation for stop-and-go waves in pedestrian dynamics based on stochastic effects. By introducing coloured noise in a stable microscopic inertia-free (i.e. first order) model, pedestrian stop-and-go behaviour can be described realistically without requirement of instability and phase transition. We compare simulation results to empirical pedestrian trajectories and discuss plausible values for the model’s parameters
The Inflection Point of the Speed-Density Relation and the Social Force Model
It has been argued that the speed-density digram of pedestrian movement has
an inflection point. This inflection point was found empirically in
investigations of closed-loop single-file pedestrian movement. The reduced
complexity of single-file movement does not only allow a higher precision for
the evaluation of empirical data, but it occasionally also allows analytical
considerations for micosimulation models. In this way it will be shown that
certain (common) variants of the Social Force Model (SFM) do not produce an
inflection point in the speed-density diagram if infinitely many pedestrians
contribute to the force computed for one pedestrian. We propose a modified
Social Force Model that produces the inflection point.Comment: accepted for presentation at conference Traffic and Granular Flow
201
- …