Adaptive Fuzzy Urban Traffic Flow Control Using a
Cooperative Multi-Agent System based on Two Stage
Fuzzy Clustering
Fatemeh Daneshfar
1
, Javad RavanJamJah
1
, Fathollah Mansoori
2
, Hassan Bevrani
1
, Bahram Zahir Azami
1
1
Department of Electrical and Computer Engineering, University of Kurdistan, Sanandaj, Iran
2
Islamic Azad University of Buin-Zahra, Buin-Zahra, Iran
daneshfar@ieee.org, j.ravanjamjah@ieee.org, fathollah.mansoori@gmail.com, bevrani@ieee.org, zahir@ieee.org
Abstract— The traffic congestion problem in urban areas is
worsening since traditional traffic signal control systems cannot
provide efficient traffic control. Therefore, dynamic traffic signal
control in Intelligent Transportation System (ITS) recently has
received increasing attention. This study devises an adaptive and
cooperative multi-agent fuzzy system for a decentralized traffic
signal control. To achieve this we have worked on a model which
has three levels of control. Every intersection is controlled by its
own traffic situation, correlated intersections recommendations
and a knowledge base which provides its traffic pattern. This
study focused on utilizing the prediction mechanism of our
architecture, it finds most correlated intersections based on a two
stage fuzzy clustering algorithm which finds most intersections
effect on a specific intersection based on clustering membership
degree. We have also developed a NetLogo-based traffic
simulator to serve as the agents’ world. Our approach is tested
with traffic control of a large connected junctions and the result
obtained is promising: The average delay time can be reduced by
42.76% compared to the conventional fixed sequence traffic
signal and 28.77% compared to the vehicle actuated traffic
control strategy.
Keywords- MAS; Intelligent Transportation System; Fuzzy
Control; Fuzzy Clustring; Traffic Light Control,
I. INTRODUCTION
Traffic congestion is a crucial problem in large cities. It is
partially caused by improper control of traffic lights, which is
not corresponding to the current traffic conditions. To alleviate
traffic congestion in urban areas, the concept of Intelligent
Transportation Systems (ITS) has been widely accepted in
developed countries. ITS is a highly promising system for
providing key solutions to current road congestion problems
[1].
The problem of intelligent traffic control has been studied
in the area of ITS for many years. We will refer to only a few
which are related to our work. The first one is the method of
Vehicle Actuated Signal Control (VA). This method controls
traffic lights by considering the number of cars waiting in the
queue to be serviced by a traffic light. When the current green
light is going to be changed to red, but the sensor can detect
that some cars have come in that range of distance, the duration
of the green light is extended further [2, 3]. Some other
methods are based on gathering traffic information during
different times of day and year to help agents to make decisions
[4, 5]. Using fuzzy control [6, 7], timed Petri Nets [8], SPSA
[9], ant algorithm [10], knowledge based multi-agent system
[11, 12], and a mobile agent [13] have also been suggested.
The domain of traffic signal control is well suited for multi-
agent based approaches owing to its distributed nature.
Researchers and practitioners have now realized that single
agent system [14], multi-agent systems and distributed artificial
intelligence are attractive because they consider the social
aspects of computer systems, ranging from human computer
interaction over distributed problem solving, to the simulation
of social systems [15].
But recently, multi-agent decentralized strategies for
controlling urban traffic networks have attracted considerable
attention. Roozemond and Rogier [16] proposed a prototype
using agent technology to control traffic signal systems.
Srinvasan and Choy [17] used advanced cooperative behaviors
to improve individual agent’s learning process, Chang-Qing
Cai and Zhao-sheng Yang [18] proposed an architecture
composed of segment agents, crossing agents and section
agents that it can realize an intelligent traffic management by
sharing information. Ferreira et al. [19] also presented a multi-
agent strategy where its agents optimize a traffic index based
on its local state and sensors, and also on information from
adjacent intersections.
It appears that all these approaches lack a unified model
and use only a fix number of neighbor intersections to predict
traffic flow (the neighborhood area in most of them is limited
with physical distance). Therefore we have proposed a model
with a high abstraction, which considers most correlated
intersections to predict traffic volume. Furthermore, each agent
has the ability to communicate; enabling each agent to
exchange relevant traffic information and cooperative with
other multi-agents through a flexible architecture. The
flexibility of this architecture is achieved through a modular
design. To control the traffic volume in each intersection, we
use three parameters:
1) Intersection Traffic volume (number of stopped cars
behind red light and flow of cars from green light).
2) Correlated intersections traffic volume.
978-1-4244-2517-4/09/$20.00 ©2009 IEEE
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