“This Old Digital City”
Virtual Historical Cedar Rapids, Iowa, circa 1900
James Cremer and Joan Severson
Computer Science, The University of Iowa
&
Digital Artefacts, LLC
Shayne Gelo
Joe Kearney
Digital Artefacts, LLC
Computer Science, The
University of Iowa
Marise McDermott and Rich Riccio
The History Center, Cedar Rapids, Iowa
Background
Grocery store encounter: neighbors Joan
Severson, undergraduate researcher in
Hank virtual environments lab at U. Iowa,
and Marise McDermott, curator at The
History Center
• Ms. McDermott wanted to do a multimedia
project on the history of Cedar Rapids
• Ms. Severson says “let’s do virtual reality
instead”
Vision
Use University of Iowa expertise and experience in
virtual environments, real-time person-in-the-loop
driving simulation, and 3D modeling to create an
engaging new exhibit
 3D virtual environments as interface to historical
archives
 create 3D virtual reconstruction of turn-of-the-20thcentury Cedar Rapids, and let people explore history in
an exciting engaging environment, accessing
multimedia historical information in appropriate
geographical setting
Background: The University of Iowa
A world leader in virtual environments for
driving simulation: NADS, IDS, Hank, and
others
NADS
(www.nads-sc.uiowa.edu)
• The National Advanced Driving Simulator. U.S. Dept. of
Transportation facility operated by U. Iowa. Cost: more than US$ 50
million. Fully operational within the next few months.
• Most advanced driving simulator in the world. High fidelity motion,
vehicle dynamics, audio, control loading, data recording, and
scenario (autonomous traffic, vehicles, and other entities) systems.
Sophisticated visual database creation and scenario and experiment
authoring tools.
• Use in many applications. Especially
driving safety and human factors
research: effects of signage, drugs
and alcohol, cell phone usage and
other distractions, anti-lock braking
systems, collision warning devices,
heads-up displays.
Hank (www.cs.uiowa.edu/~hank)
• Small simulator in Computer Science. Focus on
simulator development research and new uses of
virtual environment technology rather than very
large experiments of NADS.
• Collaboraration with Ford, IRISA (Rennes, FR), U.
Valencia (ESP).
• Primary current project: collaboration with
pyschology researchers on use of virtual bicycling
environment for child behavior studies. Children
ride instrumented stationary bicycle through
virtual town with traffic. Decisions/reactions
recorded and measured.
Hank Simulator
Hank and Virtual Urban Environments
• As part of Hank project
we developed expertise in
3D modeling for real-time
display. Created virtual
present-day Iowa City
(one student during the
summer) and
demonstrated at Iowa
State Fair 1998.
Thousands of riders over
10 days of use.
Digital Artefacts (www.digitalartefacts.com) and The
History Center (www.historycenter.org)
• Small company that grew out of the Hank group at
The University of Iowa. President Joan Severson
(and primary inspiration for and creator of TODC)
has an art and theater background, but
subsequently earned a computer science degree
because she saw virtual reality as a great medium
for her artistic skills.
• The History Center is a small museum in Cedar
Rapids, Iowa. Since opening its new building in
summer 1999 it’s had about 20,000 visitors and
5,400 students involved in its programs.
The TODC Project
• Initially: a small project with one large screen.
After presentation of ideas to local organizations
who might provide funds, including the possibility
of bigger things in the future, they said “let’s do
the big one now”.
• Goal: an interactive virtual environment in which
visitors can sit it and operate a “time machine” to
explore 3D restoration of circa 1900 city. During
exploration visitors can activate multimedia
associated with significant locations in the
environment.
Initial TODC Ideas
Physical Components
• Three large screens, each 6 feet (1.83meters) wide
and 8 feet (2.44meters) tall. 120 degree angles
between them. Enclosures behind screens house LCD
projectors and mirrors arranged for rear-projection.
• The “time machine”, an H.G.Wells-ish device with
seating for 4 or 5 adults, several controllers (joysticklike “wand”, buttons, a rocker switch), vibration
motors, lights, etc. Includes a token slot and LED
timer.
Physical components
• Four networked computers. One master, three
slaves. Each slave does graphics processing for
one screen. High-end but cost-effective PCs: offthe-shelf 933MHz IBM Intellistations. Graphics
cards: 64MB GeForce2 graphics cards in current
prototype. At opening in a few weeks, might
possibly use Intense3D Wildcat 4210 (higher
quality antialiasing, but lower overall fill rate) or
GeForce2 Ultras (if we can get them by then!)
Physical components
Physical components
Construction of the 3D Historical Model
• The most challenging part of the project. Of more
than 100 buildings modeled, 6 remain standing.
• Archivists and others gathered a variety of raw
materials
 Sandborn insurance maps: provided accurate road,
sidewalk, building footprints, dimensions, and function
(names of businesses, etc.)
 photographs, postcards, blueprints, newspapers
 city records and other documents, books with
information about colors used in the time period (all the
photographs were black-and-white or sepia-toned – we
wanted a colorful environment!)
3D Model Construction
3D Model Construction
3D Model Construction
Construction of the 3D Historical Model
• Georeferencing the raw materials,
associating images and other information
geographic location/maps was important,
critical to good 3D modeling, but time
consuming.
• Primary tools: Multigen and Photoshop, plus
a little bit of 3D Studio Max
Visualization, Interaction, and Multimedia
Software
• Custom visualization, interaction, and network
synchronization software. Developed in C++ and the
OpenGVS real-time graphics SDK.
• Master processor interacts with “time machine” via data
acquisition card (“time machine” is an expensive joystick!)
and synchronizes and controls PCs doing the 3D graphics.
Master also handles audio.
• Center PC, in addition to 3D graphics, displays MPEG2
and/or AVI video associated with locations in 3D
environment. (Video, as well as 3D graphics had to be
rotated 90 degrees – projectors are on their sides).
• The software also controls region-based playback of some
narrative audio and ambient sound.
Visitor Scenarios
• Free navigation and exploration of virtual environments can
be immersive, engaging, and entertaining.
• Does not always fit with educational goals and time
constraints of museum or similar setting
• Initial TODC goal: 5 to 10 minutes user experiences
(museum visitors each given one token that activates
environment for a certain amount of time).
• Initial scenarios: free exploration with enticement to access
content. Simple representations of characters at key
locations inviting visitor to visit. I.e. access multimedia
content associated with the location.
Visitor Scenarios
• We are developing other kinds of scenarios such as
“guided tours” in which visitor movements are more
constrained. Our experience shows that not everyone is
comfortable with the full freedom afforded by virtual
environments. They’d prefer to be shown around. In
guided tour scenarios, the gross motion paths are
controlled by the software, while the user retains some
control over speed and fine path variations.
• Determining good visitor scenarios will be a very exciting
part of this project. Certainly, our initial experiences tell us
that we should develop several types of scenarios, some
better suited to children, others to senior citizens.
Demonstration of prototype at August
2000 Iowa State Fair
• Single screen, joystick, 3D model, and multimedia content
not quite finished.
• As in 1998, many users over the course of 10 days.
• Interesting to observe: people of all ages really liked it, but
in different ways or for different reasons. Kids thought it
was cool and fun, their parents/other adults like it because
they could learn interesting things, senior citizens from the
Cedar Rapids area loved it because of the nostalgic
memories it evoked.
• Showed us we need to tailor multimedia content to
particular audiences when possible (many children want to
“leave” the multimedia content and get back to 3D realtime environment quickly. Video content not enaging
enough.
Iowa State Fair 2000
Educational Impact and Next Steps
• We are very excited about the potential
educational impact of derivatives of this effort.
We are working to take it out of the museum and
into schools. For instance, we are developing
software that will by used by area school chilren
(3rd, 4th, 11th grades initially) to participate in
many of the research, content creation, and even
3D modeling activities involved in creating TODC.
One component is map-based georeferencing
software that enables associating and accessing
content and research results with physical
locations.
More Next Steps
• Bring the city to life by adding moving
characters. Related to University of Iowa
work on scenario control and semiautonomous agents for driving simulation.
• Enable time travel. Develop 3D models and
content for other time periods.