15,673 research outputs found
Validated force-based modeling of pedestrian dynamics
This dissertation investigates force-based modeling of pedestrian dynamics. Having the quantitative validation of mathematical models in focus principle questions will be addressed throughout this work: Is it manageable to describe pedestrian dynamics solely with the equations of motion derived from the Newtonian dynamics?
On the road to giving answers to this question we investigate the consequences and side-effects of completing a force-based model with additional rules and imposing restrictions on the state variables. Another important issue is the representation of modeled pedestrians. Does the geometrical shape of a two dimensional projection
of the human body matter when modeling pedestrian movement? If yes which form is most suitable? This point is investigated in the second part while introducing a new force-based model. Moreover, we highlight a frequently underestimated aspect in force-based modeling which is to what extent the steering of pedestrians influences their dynamics? In the third part we introduce four possible strategies to define the desired direction of each pedestrian when moving in a facility. Finally, the effects of the aforementioned approaches are discussed by means of
numerical tests in different geometries with one set of model parameters. Furthermore, the validation of the developed model is questioned by comparing simulation results with empirical data
Single-file pedestrian dynamics: a review of agent-following models
Single-file dynamics has been studied intensively, both experimentally and
theoretically. It shows interesting collective effects, such as stop-and-go
waves, which are validation cornerstones for any agent-based modeling approach
of traffic systems. Many models have been proposed, e.g. in the form of
car-following models for vehicular traffic. These approaches can be adapted for
pedestrian streams. In this study, we delve deeper into these models, with
particular attention on their interconnections. We do this by scrutinizing the
influence of different parameters, including relaxation times, anticipation
time, and reaction time. Specifically, we analyze the inherent fundamental
problems with force-based models, a classical approach in pedestrian dynamics.
Furthermore, we categorize car-following models into stimulus-response and
optimal velocity models, highlighting their historical and conceptual
differences. These classes can further be subdivided considering the conceptual
definitions of the models, e.g. first-order vs. second-order models, or
stochastic vs. deterministic models with and without noise. Our analysis shows
how car-following models originally developed for vehicular traffic can provide
new insights into pedestrian behavior. The focus on single-file motion, which
is similar to single-lane vehicular traffic, allows for a detailed examination
of the relevant interactions between pedestrians.Comment: 35 pages, 10 Figures; chapter accepted for publication in Crowd
Dynamics (vol. 4
How simple rules determine pedestrian behavior and crowd disasters
With the increasing size and frequency of mass events, the study of crowd
disasters and the simulation of pedestrian flows have become important research
areas. Yet, even successful modeling approaches such as those inspired by
Newtonian force models are still not fully consistent with empirical
observations and are sometimes hard to calibrate. Here, a novel cognitive
science approach is proposed, which is based on behavioral heuristics. We
suggest that, guided by visual information, namely the distance of obstructions
in candidate lines of sight, pedestrians apply two simple cognitive procedures
to adapt their walking speeds and directions. While simpler than previous
approaches, this model predicts individual trajectories and collective patterns
of motion in good quantitative agreement with a large variety of empirical and
experimental data. This includes the emergence of self-organization phenomena,
such as the spontaneous formation of unidirectional lanes or stop-and-go waves.
Moreover, the combination of pedestrian heuristics with body collisions
generates crowd turbulence at extreme densities-a phenomenon that has been
observed during recent crowd disasters. By proposing an integrated treatment of
simultaneous interactions between multiple individuals, our approach overcomes
limitations of current physics-inspired pair interaction models. Understanding
crowd dynamics through cognitive heuristics is therefore not only crucial for a
better preparation of safe mass events. It also clears the way for a more
realistic modeling of collective social behaviors, in particular of human
crowds and biological swarms. Furthermore, our behavioral heuristics may serve
to improve the navigation of autonomous robots.Comment: Article accepted for publication in PNA
The Effect of Integrating Travel Time
This contribution demonstrates the potential gain for the quality of results
in a simulation of pedestrians when estimated remaining travel time is
considered as a determining factor for the movement of simulated pedestrians.
This is done twice: once for a force-based model and once for a cellular
automata-based model. The results show that for the (degree of realism of)
simulation results it is more relevant if estimated remaining travel time is
considered or not than which modeling technique is chosen -- here force-based
vs. cellular automata -- which normally is considered to be the most basic
choice of modeling approach.Comment: preprint of Pedestrian and Evacuation 2012 conference (PED2012)
contributio
Modeling the desired direction in a force-based model for pedestrian dynamics
We introduce an enhanced model based on the generalized centrifugal force
model. Furthermore, the desired direction of pedestrians is investigated. A new
approach leaning on the well-known concept of static and dynamic floor-fields
in cellular automata is presented. Numerical results of the model are presented
and compared with empirical data.Comment: 14 pages 11 figures, submitted to TGF'1
Quantitative Description of Pedestrian Dynamics with a Force based Model
This paper introduces a space-continuous force-based model for simulating
pedestrian dynamics. The main interest of this work is the quantitative
description of pedestrian movement through a bottleneck. Measurements of flow
and density will be presented and compared with empirical data. The results of
the proposed model show a good agreement with empirical data. Furthermore, we
emphasize the importance of volume exclusion in force-based models.Comment: 4 pages, 7 figures, 2009 IEEE/WIC/ACM International Joint Conferences
on Web Intelligence and Intelligent Agent Technologies (WI-IAT 2009), 15-18
September 2009, in Milano, Italy, 200
Analyzing Stop-and-Go Waves by Experiment and Modeling
The main topic of this paper is the analysis and modeling of stop-and-go
waves, observable in experiments of single lane movement with pedestrians. The
velocity density relation using measurements on a 'microscopic' scale shows the
coexistence of two phases at one density. These data are used to calibrate and
verify a spatially continuous model. Several criteria are chosen that a model
has to satisfy: firstly we investigated the fundamental diagram (velocity
versus density) using different measurement methods. Furthermore the
trajectories are compared to the occurrence of stop-and-go waves qualitatively.
Finally we checked the distribution of the velocities at fixed density against
the experimental one. The adaptive velocity model introduced satisfies these
criteria well.Comment: Fifth International Conference on Pedestrian and Evacuation Dynamics,
March 8-10, 2010, National Institute of Standards and Technology,
Gaithersburg, MD US
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