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Multi-Agent Behavioral Modeling of Traffic Applied to E-Vehicles
A. K. T. Ferma, W. F. Infante, R. M. Mojica, J. R. B. Polidario, C. K. B. Tan
Department of Electronics, Computer and Communications Engineering
Ateneo de Manila University
Loyola Heights, Quezon City
February 18, 2013
Abstract— The study aims to promote a feasible
implementation of an E-Vehicle system as an alternate
means of public utility in the Philippine setting. The study
will use the tools of Agent-Based Simulations as a means to
emulate real world traffic policies and gather drive cycle
data of E-Vehicles simulated in that environment. MATLAB
will then be used to analyse the drive-cycle data particular to
these set-ups in order to realize the traffic policy that can
bring the most optimized fuel consumption in the E-Vehicles.
I. INTRODUCTION
A. Objectives
The study aims to achieve the following
objectives: (1) To be able to obtain empirical data
from authorities such as NCTS and MMDA, and
gather measurements of various factors relevant to
the study, (2) Data gathering from the field, (3) To
design several traffic scenarios and policies suitable
for an E-Jeepneys transportation system, and (4) To
be able to see the degradations or improvements to
the E-Jeepney fuel consumption and overall
throughput given each of the simulated traffic
scenario.
II. REVIEW OF RELATED LITERATURE
A. Multi-Agent Based Modeling
Mathematicians, engineers, and various other
scientists have tried making solutions to problems
regarding complex systems, and as such, the most
probable method to simplify these systems to a
certain degree is to represent the individual agents
that make up the system and represent them in a
higher level. The capability of being able to model
the simplistic behaviour or these individual elements
and allowing them to interact with each other in a
simulated environment is the concept of what is
known as Multi-Agent Based modelling.
It should be noted that in Multi-Agent modelling,
the behaviour of the agents, the scale of the explicit
space in which the interactions of agents are
occurring, and the duration of their interactions
should be taken into consideration [1].
B. Motorist Behavior
The aggressive nature of Filipino traffic is heavily
attributed to what is referred to as Aggressive Lateral
Driving. This is most observable at jeepney stops
where the chances of swerving or changing lane are
greater. This behaviour affects lane utilization and
results in frequent unavoidable breaking.
Furthermore, video footages near jeepney stops show
a significant non-observance of lanes. As a part of
his study, Palmiano mentions that there is a high
frequency of lane non-observance, especially in 3-
lane to 4-lane roads. Table 1 below shows the
frequency of this non-observance in detail. Notice
that the average value of non-observance is 14.3%
while the peak is at 22% in a 5-minute interval [2].
Table 1: Frequency of Lane Observance.
C. Hybrid Electric Vehicles
An Electric Vehicle is a vehicle whose prime
mover is electric power, as opposed to conventional
vehicles which uses an internal combustion or diesel
engine. A hybrid vehicle is simply a vehicle that has
two movers. Popular implementations of hybrid
systems include the Parallel Hybrid and Series
Hybrid variants.
Parallel Hybrid vehicles are designed such that
an electric motor and/or the internal combustion
engine can be used as a prime mover. For this set-up,
the system itself, depending on the situation and the
power demand, uses either the electric motor or
combustion engine as prime mover. The set-up can
either use both engines as prime movers, where fuel
efficiency is the determining factor in which of the
two engines will be used. The internal combustion
engine can also charge the electric motor if needed.
These systems are designed with redundancy in mind
as a fail-safe option in case one of the engines break
down, the other can be used as a prime mover
instead.
The Series Hybrid model is made such that the
electric motor becomes the prime mover of the
system, while the internal combustion engine is
optimized as a driver for the battery banks, which
acts as a power supply for the electric motor. It is a
relatively simple set-up; however, the battery banks
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must be sufficiently large in order to have an
optimized system.
Figure 1: Simple Schematic of a Typical Hybrid Vehicle Design
D. NetLogo
The simulation software of choice for multi-agent
based modelling used in the study is NetLogo, which
allows easy entry level programs and accommodate
high level agent-based modelling such as in the
researcher’s case. The end result would be a traffic
system whose tendencies and trends can be observed
as data that can be easily exported for further
analyses.
Figure 2: Predator-Prey Model Simulated in NetLogo.
E. Traffic Simulations
If a particular traffic scenario is modelled
correctly, it can provide the means to produce a drive
cycle output that reflects the trend and behaviour of
traffic. Inputting the drive cycle output as an input to
a Quasi-Static Simulation Toolbox-generated Series
Hybrid vehicle in MATLAB produces efficiency
plots of the vehicles when subjected to certain
conditions and policies. This provided the
groundwork for further study involving the use of
Agent-Based modelling as a tool for traffic
engineering.
III. METHODOLOGY
A. General Overview
Figure 3: Methodological Framework
The researchers are to follow the following
methodology: (1) Data gathering from authorities, (2)
Field data gathering, (3) Simulation input
approximation, (4) Traffic policy simulations, and (5)
Software calculation.
The researchers would begin by gathering
traffic data in the form of recent Annual Average
Daily Traffic (AADT) records of major highways
from sources such as the Metropolitan Manila
Development Authority (MMDA) or academic
institutions like the National Center for
Transportation Studies (NCTS) in University of the
Philippines-Diliman.
This is followed by Actual data gathering,
both from a field location and within a vehicle. The
first part would involve taking 10-15 minute (or
longer depending on use) video samples of traffic.
The second part would involve the measurement of
vehicle-specific data such as cruising and U-turn
speeds.
These data are combined with physical data to
simulate as close as possible to real scenario.
NetLogo will be used as the simulation platform of
choice.
The drive cycle output from the NetLogo
simulations would then be used as an input to the
series hybrid electric vehicle simulated in MATLAB.
This model will then calculate and produce
efficiency plots based on the drive-cycle behaviour
generated by the NetLogo simulations.
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Figure 4: Traffic and Vehicle Simulation Set-Up.
B. Data Gathering and Results
Compare
Against
Random Stops Fixed Stops 4-Lane
w/Fixed
stops
4-Lane
w/Fixed
Stops
and
Exclusiv
e Lane
(Low
jeep
count)
Fixed
Stops
Fuel: 14.92%
decrease. Passengers:
148.78%
increase.
4-Lane
w/Fixed
stops
Fuel: 20.18% decrease.
Passengers:
724.05% increase.
Fuel: 6.18% decrease.
Passengers:
231.44% increase.
4-Lane
w/Fixed
Stops
and
Exclusive
Lane
(Low
jeep
count)
Fuel: 33.41%
decrease.
Passengers:
851.67% increase.
Fuel: 21.73%
decrease.
Passengers:
282.54% increase.
Fuel:
16.58%
decrease.
Passengers: 15.49%
increase.
4-Lane
w/Fixed
Stops
and
Exclusive
Lane
(High
jeep
count)
Fuel: 108.09% increase.
Passengers:
898.44% increase.
Fuel: 144.58%
increase.
Passengers: 301.34%
increase.
Fuel: 160.69%
increase.
Passengers: 21.16%
increase.
Fuel: 202.49%
increase.
Passengers: 4.92%
increase.
Table 4: Average percentage difference summary of best sub
cases. Compare Against Fuel Consumption
(L/100KM)
Passenger
Throughput
Random Stops 34.99 449
Fixed Stops 29.77 1117
4-Lane w/Fixed stops 27.93 3700
4-Lane w/Fixed Stops
and Exclusive Lane
(Low jeep count)
23.3 4273
4-Lane w/Fixed Stops
and Exclusive Lane
(High jeep count)
72.81 4483
Table 4: Fuel Consumption and Passenger throughput of each
best sub case.
IV. CONCLUSION
The study points to the aggressive nature of
Metro Manila traffic as the main reason of the un-
viability of E-vehicles as an alternative mode of
public utility. The constant stop and go traffic, as
well as, aggressive lateral movement of vehicles
in the Philippines are the main causes of traffic
congestion and fuel-inefficiency. These
behaviours have an adverse effect on the engine,
as well as, the loading and unloading of
passengers. However, there have been promising
results by gradually eliminating these problems
with implementing the four main cases discussed.
Lastly, although the system is far from being
perfect, it is a step in the right direction. It only
proves that there are two sides in E-vehicle
implementation one is making an efficient engine,
and another is engineering a better traffic system
for it.
REFERENCES
[1] Mitchell, Melanie. "Dynamics, Chaos and
Prediction" Complexity - A Guided Tour. New
York: Oxford UP, 2009. 14-27. Print.
[2] Palmiano, Hilario Sean, Ueda Shimpei, Tetsuo
Yai, and Daisuke Fukuda. Development Of A
Simulation System For Jeepney Stop Vicinity
Located In Front Of A Shopping Center. Thesis.
Tokyo Institute of Technology, 2003. Print.
[3] Teodoro, Rene Val R., Dr. Eng. Empirical
Analysis on the Relationship Between Air
Pollution And Traffic Flow Parameters. Thesis.
University of the Philippines Diliman, 1996.
Quezon City: 1996. Print.
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