Pedestrian Simulation in Transit Stations Using Agent-Based Analysis
Urban Rail Transit
DOI 10.1007/s40864-017-0053-5
http://www.urt.cn/
ORIGINAL RESEARCH PAPERS
Pedestrian Simulation in Transit Stations Using Agent-Based
Analysis
Ming Tang1
•
Yingdong Hu2
Received: 23 December 2016 / Revised: 7 March 2017 / Accepted: 25 March 2017
Ó The Author(s) 2017. This article is an open access publication
Abstract The research discusses experiential outcome in
the application of crowd simulation technology to analyze
the pedestrian circulation in public spaces to facilitate
design and planning decisions. The paper describes how to
connect spatial design with agent-based simulation (ABS)
for various design and planning scenarios. It describes the
process of visualizing and representing pedestrian movement, as well as pathfinding and crowd behavior study. An
ABS consists of a large number of agents, which are
controlled by simple localized rules to interact with each
other within a virtual environment, thereby formulating a
bottom-up system. The concept of the ABS has been
widely used in computer science, biology, and social science to simulate swarm intelligence, dynamic social
behavior, and fire evacuation. The simulation consists of
interacting agents which can create various complexities.
This paper describes research on using local interactions to
generate passenger flow analysis. An ABS is used to
optimize the pedestrian flow and construct the micro-level
complexity within a simulated environment. We focus on
how agent-driven emergent patterns can evolve during the
simulation in response to various design iterations. The
research extends to the agents’ interactions driven by a set
of rules and external environment. Our research method
includes data collection, quantitative analysis, and crowd
& Ming Tang
1
School of Architecture and Interior Design, University of
Cincinnati, Cincinnati, OH, USA
2
School of Architecture and Design, Beijing Jiaotong
University, Beijing, China
Editors: Haishan Xia and Chun Zhang
simulation on two train stations and surrounding areas in
Sihui train station in Beijing, and Xuzhou, China. By
proposing a mix-use program with the local public transportation system, the new development is integrated with
the existing urban infrastructure and public space. Through
the multi-agent simulation, we evaluate the crowd flow,
total travel time, density, and public accessibility. Based on
the result of ABS, we discussed whether various space
design methods can improve pedestrian flow efficiency and
passenger experience, as well as shortening transfer time,
and reducing congestion.
Keywords Agent-based simulation Pedestrian flow
analysis Self-organizing
1 Introduction
There were many computational methods applied to simulate agents involving movement, including ‘‘the simple
statistical regression, spatial interaction theory, accessibility approach, space syntax approach and fluid flow analysis’’ [1]. Michael Batty described the property of
‘‘Autonomy’’ and ‘‘the embedding of the agent into the
environment’’ as two key properties of agents in an agentbased system (ABS). An ABS consists of numerous agents,
which follow localized rules to interact with a simulated
environment, thereby formulating a bottom-up system.
Since Craig Reynolds’ artificial ‘‘bodies’’ and flock simulation, the concept of ABS has been widely used to study
decentralized systems that include human social interaction. In urban modeling, agents can be defined as autonomous ‘‘physical or social’’ entities or objects that act
independently of one another [1]. ABS focuses on agents’
properties and processes, responsible for responding to
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Urban Rail Transit
external changes, specifically how agents can ‘‘sense’’ and
‘‘act’’ to form a complex system. The movements are
usually based on simple rules such as separation, alignment, and cohesion. Computer scripts can be used to
control agent’s velocity, maximum force, range of vision,
and other properties.
In the early research phase, we compared the bottom-up
ABS with cellular automation (CA) methods, as well as
space syntax, to examine agents’ generation, spatial properties, and interaction with the environment.
1.1 Comparing ABS with Cellular Automation
Cellular automation (CA) calculates cells’ changing state
through time, based on the state of neighboring cells and
context. As two famous bottom-up systems, both CA and
ABS compute the status of a changing object over time.
However, it is important to understand the distinction
between cells and agents. Batty describes agent as ‘‘mobile
cells, which—objects or events that located with respect to
cells but can move between cells’’ [1]. However, the
behaviors of CA are often unpredictable and lack purposive
planning goals. It is difficult to use CA to add rules and
other ‘‘purposive goals’’ to the system beyond context
awareness. Similar to Betty’s global attraction surface in
his study on the agent’s movement, we need a system to
introduce external force rules to influence the agents’
behavior.
1.2 Comparing ABS with Space Syntax
Space syntax is another method to study movement pattern
and accessibility of a network based on lines, nodes, and
connections. With its own ‘‘agent analysis’’ tool, space
syntax does not actually measure the interactions among
agents, but provides fast feedback between geometric elements and their accessibility value within a grid of cells.
We studied space syntax as a reference tool for ABS.
Through importing the College of Design Architecture Art
and Planning (DAAP) building floor plan into space syntax
analysis tool, we produced heat map to represent accessibility and spatial integration. Warmer colors represent
higher spatial integration values. We computed the integration value of each cell by using the analysis tools in
space syntax and visualized the values with colors. The
qualitative values extracted from the space syntax analysis
are imported into Grasshopper for further computing. In
order to convert the space syntax results into a heat map
representation, we created a data processing method to
expand the color values automatically from paths to zones.
It became obvious that even though space syntax provided
a fast way to visualize interactions between agents and
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environment, however it cannot simulate the interactions
among agents such as complex social behavior.
We also researched several other commercial agentbased tools in the entertainment industry. Mass animation
tool has been widely used to simulate the behavior of
crowds, where the agents’ movements are computed based
on the interaction among themselves, as well as the interaction with the environment. We explored A* pathfinding
an algorithm used to create the cognitive agents, which can
populate a spatial model and navigate through a ‘‘cell’’based map. Different from the ‘‘reactive’’ agent in Reynolds’ flock simulation, these cognitive agents have their
artificial intelligence (AI). The agents have the ability to
respond to the changing en (...truncated)