Case Study
Development of Virtual Driving Simulator
for Transportation Research
M. K. Abdul Jalil, PhD
Faculty of Mechanical Engineering
Universiti Teknologi Malaysia
Johor, Malaysia
This presentation…
To share with you our short research experience
of developing a static base driving simulator
 Basis for vehicle related reach activities in the
future
 Development of basic research in computational
and visualization areas
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Introduction

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

Virtual reality is a technology allows user to feel immersed
in a computer-generated environment
A virtual driving simulator is a virtual reality device allows
its user to feel a life-like experience of driving an actual
vehicle
A driving simulator is cost effective tool to enable analysis
on driving characteristics, and interaction between visual
database and vehicles
A low cost PC-based static driving simulator can be used
to develop VR related system
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History of Driving Simulator
Root on flight
simulator in
early 1900s
Daimler-Benz
high-fidelity
driving simulator
in 1985 with the
advent of
computer
technologies
Advanced
driving
simulator
constructed
since 1990s
The most sophisticated
driving simulator around the
world, NADS in Iowa
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Advanced Simulator

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Capable of simulating the dynamic
motions and scenes of actual
vehicle with high fidelity
simulation output
Construction cost is very high with
consists of a visual system, control
feel system, dynamic feedback
platform, auditory system and
complex full developed vehicle
dynamic model
Examples: National Advanced
Driving Simulator (NADS), Leeds
Advanced Driving Simulator (LADS)
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Why Driving Simulator?
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Vehicle Prototyping – new vehicle design, ride
and handling
Safety Related Issues – DWI, Cellular Phone,
Driving endurance, blind spot
Drivers Training – truck simulators, train
simulators
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Components
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Visual database -
simulation of
surrounding environment, including
other vehicles
Vehicle Dynamic Model
(VDM) - simulation of the physics of
vehicle model and the road surface

‘Driving Cab’


A system that enables the operator
to interpret the state of the model
such as visual display
Control devices, such as steering
wheel, brake pedal and throttle
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Our Research ..
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Static base simulator
PC based, low-cost, with sufficient graphic quality
Components

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visual database – audio + visual database
VDM
Vehicle control – accelerator, steering, brake
As a groundwork and preliminary attempt to develop
an advanced driving simulator for vehicle related
research
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System Architecture
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Hardware
To PCI
slot of
Server
CPU
NI PCI 6024E, 200 kS/s, 12-Bit,
16 Analog Input Multifunction
DAQ
CB-68LP, 68-Pin Digital and
Trigger I/O Terminal Block
3 Potentiometers
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Issues …
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Visual Database Rendering cost

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Simulation Frame-rate & Fidelity of Vehicle Driving
Simulator
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Effective way of producing a detailed image, without using too much computer
power
Graphic optimization is implemented – LOD
Large graphical delays mean a great risk of the driver getting dizzy even if the
screen has good acuity
Acceptable frame-rate to human user (approx 40 frame/second)
Enough quality and temporal response for driving tasks and maneuvers
Real-time Computation of Vehicle Dynamic Model (VDM)


The ability to run in real time depends on the integration time step and the
complexity of the vehicle dynamic model
6 DOF VDM is used
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Visual Database
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VR environment is developed using WorldToolKit
(WTK) programming language.
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All models created using AutoCAD & 3D Studio
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WTK reads these models into the VR environment and
manage them under Scene Graph

WTK universe includes:

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Static models – sky, landscape, buildings, road, barriers, lights
Effects – fog, sound
Transform node – driver’s view port in VR environment
Position information – current position data extraction
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Scene Graph Management
Universe
Root Node
Light Node
Group Node
Transform
Node
Position
Information
Geometry
Node
Driver View port
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Graphic Construction &
Optimisation
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Shell Modeling
Texture Mapping
Visible Facet
Foggy Effect
Recursion Technique
Collision Detection
Level of Detail (LOD)
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Shell Modeling
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Models loaded into WTK
are prepared in 3D shell
(rather than solid) for
polygon reduction.
Shell modelling reduces
memory usage in the
rendering of model
internal parts
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Texture Mapping
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Texture mapping to
improve visual database
realism
Real photo images were
taken by using digital
camera and exported in
.jpeg format
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Visible Facet

Visible facet of building
containing window
frames and wall are
created using single
polygon with wall
textures image mapped
on the polygon to
minimize graphical
complexity
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Fog Effect
Driver visibility
 Linear model used

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Collision Detection
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Realistic road driving
simulation
Against curbs, buildings,
etc
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Level of Detail (LOD)
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Closer objects – good
graphics
Far objects – minimal
rendering
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WTK Virtual Environment
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Network Data Transmission
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Transmission Control Protocol / Internet
Protocol (TCP/IP) was employed as the
data transmission protocol between 2
PC’s
TCP is a connection-based protocol
designed to ensure smooth data transfer
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Vehicle Dynamic Model (VDM)
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The vehicle dynamic model
is computed using MATLABSIMULINK program in the
server computer
SIMULINK S-function block
constructs a TCP/IP port for
data interface with the
client computer
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Handling Dynamic Model
The velocities components and from
vehicle velocity, and its sideslip angle, in
the equations
u  V cos 
v  V sin 
Equations of motion of handling system
 
X
 
Y

  cos 

  sin 


 sin    u 
 
cos    v 
  N  ( mV  Y )  N  Y 

 N ( mV  Y )  N Y 


  

 
Handling Coefficients Corresponds
To Velocity (Courtesy from Motor
Vehicle Dynamic, World Scientific)

 
N

Y N


 N  Y
( mV  Y  )  N  Y 




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Handing and Cornering Effect
The view port is from the position of vehicle c.g.
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Quarter-Car Model
A two-degree of freedom quarter-car model
is suitable to examine the forces acting on
the suspension system natural frequency up
to 30-50Hz
F sfl  k
fl
( Z ufl  Z sfl )


F dfl  C S ( Z ufl  Z
sfl
)
F tfl  k tfl ( Z rfl  Z ufl )


F dtfl  C St ( Z rfl  Z ufl )
Arrange in the form of Newton’s Second
Law,
the
unsprung
mass
vertical
acceleration is computed

F tfl  F sfl  F dfl  F dtfl  m ufl Z ufl
Quarter-Car Model

Z ufl 
Ftfl  F sfl  F dfl  F dtfl
m ufl
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Full-Car Model
The result obtained from quarter-car model is substituted into
Full-car model. The equation of motions of suspension system are
F

 mB Z b


M

M Y  I YY 
X
 I XX 

Hence, the variables of
dynamic model is obtained

Z
b

F fl  F fr  F rl  F rr
mB

 
( F fl  F rl )(
a
2
)  ( F fr  F rr )(
a
)
2
Full-Car Model
I XX

 
( F rl  F rr )(
b
2
)  ( F fl  F fr )(
I YY
b
2
)
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Visualization of Suspension Response
The view port is from the position of vehicle c.g.
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Suspension Response of Vehicle
Road Input, [Z]
Vertical
Translation, z
Roll angle
Pitch angle
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Conclusion

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Our first attempt to develop a low-cost
static base driving simulator using VR
technology is almost completed.
This project provides the groundwork for
future development of advanced driving
simulator.
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(EVRG)
ICPDD ’04, Kota Kinabalu
Future work
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Integration of Motion base
Development of traffic simulation
Comprehensive database development
More efficient computational and graphics
rendering methods – parallel rendering, better
approximation methods
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(EVRG)
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Thank You
Contact:
kasim@fkm.utm.my
© Engineering Visualization Research Group
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