HPL EQUIPMENT AND CAPABILITIES
HPL Advanced Driving Simulator / STI Simulator Trainer / Eye Tracker & Other Equipment
HPL Advanced Driving Simulator
The centerpiece of the Human Performance Laboratory (HPL) is the Advanced Driving Simulator (Figure 1). The simulator has been in operation at the Human Performance Lab since 1996. It has been an integral part of dozens of research projects whose focus has included topics as varied as driver training and assessment, hazard anticipation, attention maintenance, decision making, driver distraction, cell phones, lane changing, pavement markings, traffic control sign and signal design (both on the road and in tunnels), advanced traveler information systems, forward collision warning systems, and in-vehicle music retrieval systems. In recent months the software and computer hardware underwent a complete upgrade in November of 2008. While the car and projection screens are the same as before, the new simulator software for scene and scenario development is part of a brand new Realtime Technologies Inc. (RTI) driving simulation platform – which has increased the fidelity of the vehicles, buildings and roadways of the virtual environment and significantly increased the lab’s data collection and analysis capabilities.
Figure 1: HPL Advanced Driving Simulator
SIMULATOR HARDWARE: The
vehicle cab in the HPL Advanced Driving Simulator is a full sized Saturn
sedan. A driver operates the controls of
the Saturn just as he or she would on the road.
The visual world is displayed on three screens, one in front of the car
and two on each side. Each screen
subtends 60 degrees in the horizontal direction and 30 degrees in the vertical
direction. As the driver turns the
wheel, brakes or accelerates, the roadway that is visible to the driver changes
appropriately. The images themselves are
updated 60 times a second using a network of four advanced RTI simulator
servers which parallel process the images projected to each of the three
screens using high end multimedia video processors. The image resolution on each screen can be as
high as 1024 ×768. The sound system
for the simulator consists of three Logitec Dolby 2.1 Surround Sound speakers,
two located on the left and right sides of the car and one, a sub-woofer,
located in front of the car. The system
provides realistic road, vehicle, wind and other noises with appropriate
direction, intensity and Doppler shift.
SIMULATOR SOFTWARE: The
simulator is run by four custom-built rack-mounted servers provided by
RTI. Each of three servers are
responsible for processing visual database, dynamic objects and driver
point-of-view and projecting these images onto the three simulator
screens. Three software packages make it
possible to develop the virtual environment and program the driving
scenarios. A program called Sim Creator
is the software responsible for the coordination of all aspects of the
system. Sim Creator takes inputs from
the car (steering angle, throttle, brake, turn indicators, etc.) and the system
(scripts, virtual database, scenario parameters, data files, scenario
definitions) and outputs the appropriate scenes to the projectors in real
time. A second software package called
Internet Scene Assembler (ISA) allows for the construction of virtual
environments from a library of uploaded roadway tiles. Custom vehicle paths and behaviors can be
programmed using a combination of predefined sensor objects and
JavaScript. Both autonomous vehicles
(random vehicles put in the environment and controlled by the computer based on
desired traffic density) and scripted vehicles (specific vehicles placed by the
programmer to behave in some predetermined way for each participant) can be
programmed in ISA. Vehicles in the
virtual environment are very realistic in the way they move and behave. Finally, custom geometry, road tiles and
traffic paths can be built in a 3-D modeling program called Multigen
Creator. Multigen geometry and paths can
then be uploaded directly to ISA as tiles for use in our simulations. Sim Creator and ISA are both completely open
source, allowing us unprecedented flexibility in the types of data we
collect. This flexibility also allows us
to upgrade the system easily and/or incorporate new study-specific,
custom-built hardware into the simulation system for testing purposes. Thus, we can easily create scenes and
scenarios to study the research areas of interest to Hyundai: Lane Departure
Warning, Blind Spot Detection, Forward Collision Warning, and Adaptive Cruise
Control.
DATA COLLECTION &
ANALYSIS: The HPL Advanced Driver Simulator is
extremely flexible in its ability to provide both common and uncommon types of
data to the researchers using it.
Typical parameters such as throttle position, velocity, direction of
travel, steering angle, lane position, braking,
and signaling are automatically recorded at up to 60 Hz (can be user
specified), not only for the participant’s vehicle (ownship) but also for any
vehicle specified by the experimenter.
In addition, video signals from the simulator are easily recordable on
digital tape for later replay and analysis.
However, the system’s data collection capabilities go far beyond the
most typically recorded parameters.
Because the system is open source, custom JavaScript code can be written
to record just about any parameter required for a study. For instance, if a study requires that the
distance from ownship and a pedestrian about to step into the road be recorded,
JavaScript code can be included in the model to record the distance between
those two objects starting at some predefined point and ending after ownship
has passed (or hit) the pedestrian. As
mentioned earlier, custom hardware can also be incorporated into the simulator
with minimal effort for such things as testing displays, in vehicle devices
(GPS, IPod, collision warning systems, etc.) and data from the hardware
recorded along with the systems typical parameters.
In 2009, the Human Performance Laboratory received a second driving simulator to complement our research in driver training human factors. The new simulator is a Systems Technologies Inc. (STI) driving simulation system (Figure 2). The new simulator will be primarily be used for driver training research. The advantage of the STI system is that it is a very powerful driving simulator system for an affordable cost. The system has an extremely large user base in the driver’s education, insurance, and training research community. While our system will be somewhat upsized compared to the typical STI system in the field, the fact that our platform will operate using the
same software
and basic hardware
components means our research
findings will be more easily generalized
for use in the field and will greatly increase our ability to collaborate with
other organizations using the same system for projects such as training
research or large-scale field studies. Sharing an STI system’s scenarios
and visual databases is as easy as emailing a single file to another
user.
Figure 2: STI Simulator Hardware
SIMULATOR HARDWARE: For
our new system, a custom-built simulation platform is being constructed. The new system will utilize an adjustable
driver’s chair and steering/pedal console.
Three 60″ diagonal screens will be directly in front of the
driver, subtending at least 160 degrees visual angle. Roadway images will be projected to the
screens using state-of-the-art short throw projectors which can be placed
directly below the screens, eliminating the need for ceiling mounted projectors
and allowing for a more compact simulator set up. The sound system for the simulator will
consist of three Logitec Dolby 2.1 Surround Sound speakers, two located behind
the screens to the left and right of the participant, and a sub-woofer, located
in front of the participant.
SIMULATOR SOFTWARE: The
STI simulator is operated using three high-end graphics computers operating in
parallel. The center channel computer
controls vehicle and environmental dynamics as well as the view projected to
the center screen. The left and right
channel computers control views on the left and right screens. Images are projected at a resolution of
1024 × 768 and are refreshed at 60 Hz. Tiles and scenarios are programmed directly
in STI’s simulator software,
DATA COLLECTION & ANALYSIS: The
STI simulator system automatically records the most common driving parameters
such as throttle position, velocity, direction of travel, steering angle, lane
position, braking, and signaling. Data
concerning the participant’s vehicle relative to other vehicles in the
environment can also be recorded (such as following distance). Events can be programmed and data relative to
those events recorded. Also, because the
system was designed with training in mind, data relative to the “rules of the
road” are recorded. For instance,
drivers may be “fined” for running stop signs or failing to use indicators
during a turn. Attention maintenance and
secondary tasks can also be programmed in STISIM and that data recorded in the
data file. One of the most powerful
features of the STI simulator is its ability to instantly replay drives
immediately after a drive is concluded.
This is an extremely useful feature for training purposes, allowing for
immediate feedback to be provided for the driver.
The HPL also
possesses a large array of other equipment for use in research studies. The lab owns two eye tracking systems that
are used for transportation studies. The
lab’s primary eye tracker for simulator and field studies is the ASL Mobile Eye
eye tracking system. Mobile Eye is an
ultra-lightweight, highly portable system that can be used either in the
simulator or in the field. The system consists
of a pair of goggles that contain miniaturized optics – a camera for viewing
the eye, another for viewing the scene ahead, an ultraviolet light source, and
a small reflective spectacle to allow the eye camera to see the eye without
being directly in front of the participant’s eye (Figure 3). The scene and eye data are recorded on a
portable DVCR which can be clipped to the participant’s belt or placed on the
passenger seat for later analysis.
Special software is used to overlay the driver’s calculated point of
gaze on the video of the scene ahead (Figure 4).
Figure 3: ASL Mobile Eye II Eye Tracker
Figure 4: Crosshairs on Scene Output
Indicate
Participant's Point of Glaze
The lab’s other transportation eye
tracker is an ASL 5000 head mounted system (Figure 5).
Being another ASL system, the optics operate in much the same way. However, the ASL 5000, rather than using a
scene camera, uses the output of the simulator’s video signal as the
scene. Eye position is calculated using
a combination of eye and head position, which is calculated using a magnetic
head tracking system that is integrated with the simulator. Eye point-of-gaze is then overlaid on the
video of the simulator output. The lab
also owns a third eye tracking system for PC-based training studies (SMI eye
tracker).
Figure 5: ASL Headed Mounted System
The lab also has a large array of equipment for use in field studies. The lab uses a Vericom system for recording the on-board diagnostics of vehicles in the field. Data from other devices such as global positioning units or range finders can be recorded by the Vericom. The lab has also developed a means of easily recording video in the field. The lab’s “Four-Cameral Mobile Lab” system (Figure 6) can digitally record up to four video channels and contains mounting for three roof-mounted cameras and one head-mounted camera. The system is configured to be installed in any vehicle within minutes and can be removed just as quickly.
Figure 6: Four Camera Mobile Lab System
last updated 8/11/2009 (tmz)