Kazumichi Ohtsuka

Introduction of frictional and turning function for pedestrian outflow with an obstacle

In this paper, two important factors which affect the pedestrian outflow at a bottleneck significantly are studied in detail to analyze the effect of an obstacle setup in front of an exit. One is a conflict at an exit when pedestrians evacuate from a room. We use floor field model for simulating such behavior, which is a well-studied pedestrian model using cellular automata. The conflicts have been taken into account by the friction parameter. However, the friction parameter so far is a constant and does not depend on the number of the pedestrians conflicting at the same time. Thus, we have improved the friction parameter by the frictional function, which is a function of the number of the pedestrians involved in the conflict. Second, we have presented the cost of turning of pedestrians at the exit. Since pedestrians have inertia, their walking speeds decrease when they turn and the pedestrian outflow decreases. The validity of the extended model, which includes the frictional function and the turning function, is supported by the comparison of a mean-field theory and real experiments. We have observed that the pedestrian flow increases when we put an obstacle in front of an exit in our real experiments. The analytical results clearly explains the mechanism of the effect of the obstacle, i.e., the obstacle blocks pedestrians moving to the exit and decreases the average number of pedestrians involved in the conflict. We have also found that an obstacle works more effectively when we shift it from the center since pedestrians go through the exit with less turning.

Simulation of space acquisition process of pedestrians using Proxemic Floor Field Model

We propose the Proxemic Floor Field Model as an extension of the Floor Field Model, which is one of the successful models describing pedestrian dynamics. Proxemic Floor Field is the Floor Field which corresponds to the effect of repulsion force between others. By introducing the Proxemic Floor Field and threshold, we investigate the process that pedestrian enters a certain area. The results of simulations are evaluated by simple approximate analyses and newly introduced indices. The difference in pedestrian behavior due to the disposition of the entrance is also confirmed, namely, the entrance in the corner of the area leads to the long entrance time because of the obstruction by pedestrians settling on the boundary cells.

Towards an agent-based proxemic model for pedestrian and group dynamics: motivations and first experiments

The simulation of pedestrian dynamics is a consolidated area of application for agent-based models: successful case studies can be found in the literature and off-the-shelf simulators are commonly employed by end-users, decision makers and consultancy companies. These models, however, generally neglect or treat in a simplistic way aspects like (i) the impact of cultural heterogeneity among individuals and (ii) the effects of the presence of groups and particular relationships among pedestrians. This work is aimed, on one hand, at introducing some fundamental anthropological considerations on which most pedestrian models are based, and in particular Edward T. Halls work on proxemics. On the other hand, the paper describes an agent-based model encapsulating in the pedestrians behavioural model effects representing both proxemics and a simplified account of influences related to the presence of groups in the crowd. The model is tested in a simple scenario to evaluate the implications of some modeling choices and the presence of groups in the simulated scenario. Results are discussed and compared to experimental observations and to data available in the literature.Models for the simulation of pedestrian dynamics and crowds of pedestrians have already been successfully applied to several scenarios and case studies, off-the-shelf simulators can be found on the market and they are commonly employed by end-user and consultancy companies. However, these models are the result of a first generation of research efforts considering individuals, their interactions with the environment and among themselves, but generally neglecting aspects like (a) the impact of cultural heterogeneity among individuals and (b) the effects of the presence of groups and particular relationships among pedestrians. This work is aimed, on one hand, at clarifying some fundamental anthropological considerations on which most pedestrian models are based, and in particular Edward T. Hall’s work on proxemics. On the other hand, the paper will briefly describe the first steps towards the definition of an agentbased model encapsulating in the pedestrian’s behavioural model effects capturing both proxemics and influences due to potential presence of groups in the crowd.

Mobility analysis of the aged pedestrians by experiment and simulation

In coming decade, the aging rate will dramatically increase in advanced countries.Focus on the mobility issues where the elderly and young pedestrians are mixed.Cellular Automata model is created with aid of experiments.The model shows reasonable consistency with the experimental result.The compatibility of elderlys safety and youngs mobility is discussed. The relative weight of the population shifts from younger to elderly in the most of the region on the planet. Current aging rate in the advanced nations varies from 12% to 13% and is expected to increase up to 21-37% in 2050. The increase of aging rate in the society especially in the large city will lead a mobility problem. From a social quality point of view, it is important to achieve the compatibility between safety and mobility respectively for younger and elderly generation. For the purpose of understanding the basic characteristics of the pedestrian dynamics under cohabitation of younger and elderly generation, a Cellular Automata (CA) model is created with the aid of pedestrian experiments. Simulations are carried out to reproduce the experimental results and had shown a good agreement.

An Agent-Based Pedestrian and Group Dynamics Model Applied to Experimental and Real-World Scenarios

Pedestrian simulation is a consolidated area of application in which agent-based models are often employed; successful case studies are described in the literature and commercial, off-the-shelf simulators are commonly employed by decision makers and consultancy companies. Most state-of-the-art models, however, generally do not consider the explicit representation of pedestrians aggregations (groups) and their implications on the overall system dynamics. This work is aimed at discussing the relevance and significance of this research effort with respect to the need of empirical data about the implication of the presence of groups of pedestrians in different situations (e.g., changing density, spatial configurations of the environment). The article describes an agent-based model encompassing both traditional individual motivations (i.e., tendency to stay away from other pedestrians while moving toward the goal) and a simplified mechanism considering the cohesion effects related to the presence of groups in the crowd. The model is tested in a simple scenario to evaluate the implications of some modeling choices and the presence of groups in the simulated scenario. Moreover, the model is applied in a real-world scenario characterized by the presence of organized groups as an instrument for crowd management. Results are discussed and compared to experimental observations and to data available in the literature.

An agent-based proxemic model for pedestrian and group dynamics: motivations and first experiments

The simulation of pedestrian dynamics is a consolidated area of application for agent-based models: successful case studies can be found in the literature and off-the-shelf simulators are commonly employed by end-users, decision makers and consultancy companies. These models, however, generally neglect or treat in a simplistic way aspects like (i) the impact of cultural heterogeneity among individuals and (ii) the effects of the presence of groups and particular relationships among pedestrians. This work is aimed, on one hand, at introducing some fundamental anthropological considerations on which most pedestrian models are based, and in particular Edward T. Halls work on proxemics. On the other hand, the paper describes an agent-based model encapsulating in the pedestrians behavioural model effects representing both proxemics and a simplified account of influences related to the presence of groups in the crowd. The model is tested in a simple scenario to evaluate the implications of some modeling choices and the presence of groups in the simulated scenario. Results are discussed and compared to experimental observations and to data available in the literature.Models for the simulation of pedestrian dynamics and crowds of pedestrians have already been successfully applied to several scenarios and case studies, off-the-shelf simulators can be found on the market and they are commonly employed by end-user and consultancy companies. However, these models are the result of a first generation of research efforts considering individuals, their interactions with the environment and among themselves, but generally neglecting aspects like (a) the impact of cultural heterogeneity among individuals and (b) the effects of the presence of groups and particular relationships among pedestrians. This work is aimed, on one hand, at clarifying some fundamental anthropological considerations on which most pedestrian models are based, and in particular Edward T. Hall’s work on proxemics. On the other hand, the paper will briefly describe the first steps towards the definition of an agentbased model encapsulating in the pedestrian’s behavioural model effects capturing both proxemics and influences due to potential presence of groups in the crowd.

Inflow Process: A Counterpart of Evacuation

We propose a new concept,“inflow process” of pedestrians as a counterpart of an evacuation process. In the inflow process, pedestrians enter a limited area without hurrying. This type of pedestrian motion can be observed in our daily life, e.g. in elevators, trains, etc. From experimental observation, we found intriguing behaviors, including pedestrians’ preference for boundaries, collective orientation, etc. Besides, the inflow process has contrastive aspects to evacuation process. For this reason the process is important for the pedestrian dynamics field.

Inflow Process of Pedestrians to a Confined Space

To better design safe and comfortable urban spaces, understanding the nature of human crowd movement is important. However, precise interactions among pedestrians are difficult to measure in the presence of their complex decision-making processes and many related factors. While extensive studies on pedestrian flow through bottlenecks and corridors have been conducted, the dominant mode of interaction in these scenarios may not be relevant in different scenarios. Here, we attempt to decipher the factors that affect human reactions to other individuals from a different perspective. We conducted experiments employing the inflow process in which pedestrians successively enter a confined area (like an elevator) and look for a temporary position. In this process, pedestrians have a wider range of options regarding their motion than in the classical scenarios; therefore, other factors might become relevant. The preference of location is visualized by pedestrian density profiles obtained from recorded pedestrian trajectories. Non-trivial patterns of space acquisition, e.g., an apparent preference for positions near corners, were observed. This indicates the relevance of psychological and anticipative factors beyond the private sphere, which have not been deeply discussed so far in the literature on pedestrian dynamics. From the results, four major factors, which we call flow avoidance, distance cost, angle cost, and boundary preference, were suggested. We confirmed that a description of decision-making based on these factors can give a rise to realistic preference patterns, using a simple mathematical model. Our findings provide new perspectives and a baseline for considering the optimization of design and safety in crowded public areas and public transport carriers.

Experimental investigation of pedestrian personal space

New generations of computer-based simulations of pedestrian crowd dynamics are aimed at improving both scientific knowledge about such complex social phenomena and practical use of the results for more efficient, safer management of pedestrian circulation dynamics in urban scenarios. Within this twofold framework, the validation of the developed models with field data plays a central role, and the acquisition of empirical evidence about human behavior during locomotion is mandatory. An empirical investigation of pedestrian personal space (i.e., the area surrounding an individual while walking and into which strangers cannot intrude without causing discomfort) is reported. The investigation was developed in an ad hoc experimental setting to collect meaningful data (e.g., measurements of the front zone of personal space under static and moving conditions). The main results are presented to illustrate both the adopted experimental setting and the related data-collection method. These results represent an innovative contribution toward defining a metric for the characterization of spatial interactions among pedestrians and allowing the validation of simulation models dedicated to the study of the dynamic behavior of pedestrian crowd phenomena.

An Agent-Based Proxemic Model for Pedestrian and Group Dynamics: Motivations and First Experiments

The simulation of pedestrian dynamics is a consolidated area of application for agent-based models: successful case studies can be found in the literature and off-the-shelf simulators are commonly employed by end-users, decision makers and consultancy companies. These models, however, generally neglect or treat in a simplistic way aspects like (i) the impact of cultural heterogeneity among individuals and (ii) the effects of the presence of groups and particular relationships among pedestrians. This work is aimed, on one hand, at introducing some fundamental anthropological considerations on which most pedestrian models are based, and in particular Edward T. Halls work on proxemics. On the other hand, the paper describes an agent-based model encapsulating in the pedestrians behavioural model effects representing both proxemics and a simplified account of influences related to the presence of groups in the crowd. The model is tested in a simple scenario to evaluate the implications of some modeling choices and the presence of groups in the simulated scenario. Results are discussed and compared to experimental observations and to data available in the literature.Models for the simulation of pedestrian dynamics and crowds of pedestrians have already been successfully applied to several scenarios and case studies, off-the-shelf simulators can be found on the market and they are commonly employed by end-user and consultancy companies. However, these models are the result of a first generation of research efforts considering individuals, their interactions with the environment and among themselves, but generally neglecting aspects like (a) the impact of cultural heterogeneity among individuals and (b) the effects of the presence of groups and particular relationships among pedestrians. This work is aimed, on one hand, at clarifying some fundamental anthropological considerations on which most pedestrian models are based, and in particular Edward T. Hall’s work on proxemics. On the other hand, the paper will briefly describe the first steps towards the definition of an agentbased model encapsulating in the pedestrian’s behavioural model effects capturing both proxemics and influences due to potential presence of groups in the crowd.