maqueta final

RESUMEN
ABSTRACT.
Executed in the C2 virtual reality space, a Virtual
Architectural Design Tool (VADeT) was developed
to explore factors involved in design in full scale. C2
is a synthetic CAVE environment providing a fullscale setting for image projection and perception.
Applying this tool for design has four advantages
over other CAD systems. First, it enables navigation
performance in full scale to create a sense of immersion and reflection of the seeing-as. Second, it
allows creation, modification, and editing of threedimensional objects in a virtual space. Third, designs
can be modified and viewed simultaneously either
inside or outside of the generated model to obtain
the best design product. Fourth, the entire design
process can be recorded and played back.
Collectively,
this 1
tool1serves
1 0 0 1
0 1the0purposes
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1 (1) a
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three-dimensional sketching tool for manipulating 3D objects, (2) a study tool for transparently
displaying the design processes, and (3) a teaching
tool to demonstrate the processes of how designers design. Thus, design in a full-scale representation
not only is possible, but also is an unconventional
mode that influences design thinking.
keywords:
Design cognition, perception, design tools, virtual
reality.
Elaborada en el espacio de realidad virtual C2,
las herramientas del diseño virtual de Arquitectura fueron desarrolladas para explorar factores que involucran un diseño a escala real.
La C2 es una cabina de ambiente sintético
que genera imágenes a escala para percep0 1de0diseño
0 1 1 0 0 1 1 1 0 1 0 0 0
ción. Aplicando esta herramienta
tiene cuatro ventajas sobre los sistemas CAD.
Primero: permite la navegación en escala real
creando un sentido de inmersión y reflexión
de lo visto. Segundo; permite creación, modificación y edición de objetos tridimensionales
en ambientes virtuales. Tercero; los diseños
pueden ser modificados y vistos simultáneamente tanto de afuera como de adentro del
modelo generado para obtener el mejor producto. Cuarto; el proceso de diseño puede
ser grabado y revisado nuevamente. Colectivamente, esta herramienta tiene el propósito
de: (1) elaborar un esbozo tridimensional para
manipular el objeto en 3D, (2) desplegar de
manera transparente el proceso de diseño y
(3) demostrar el proceso académico de cómo
los diseñadores diseñan. Por lo que, el diseño
en una representación a escala real, no-solo
es posible sino que es un método no convencional que influye en la actitud del diseño.
Palabras claves:
Diseño cognoscitivo, percepción, herramientas
de diseño, realidad virtual.
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Chiu-Shui Chan, Ph.D
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.Virtual Reality Applications Center /
Architecture Iowa State University
[email protected]
Design in a Full-scale
Immersive Environment
How feasible is it to design in full scale? Why would
designers want to design that way? If full-scale
design is worth doing, then how can it be done?
Can technology be utilized to make it possible? If it
is possible, then in what aspects that would affect
or alter design thinking? These are interesting, bold
questions for design educators and researchers to
explore. This project intends to take a lead in this
regard.
1. Why not design in full scale?
Traditionally, architectural design begins with an
idea in mind; then, either a two-dimensional
concept is sketched on paper or a three-dimensional study model is constructed to visually perceive
the form and to evaluate the design product. Rarely
will a designer do design in full scale.
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Design in a full-scale Immersive environment/Chiu Shui Chan/ ConVEACA
2001
This is due to economic and logistic constraints that
prevent designers from creating full-scale drawings
or building full-scale models for large architectural
projects. Thus, designs are typically done in small
scale. However, conventions of sketching on paper
and constructing miniature models are very much
culture-bound. Even though the conventional
methods provide a means for cultivating ideas, they
set up certain limits on stimulation and inspiration.
Because designers cannot physically project
themselves into the space in the same way as they
physically exist, the experiences of seeing-as and
reflection in-action1 are limited, and the scope of
design thinking is narrowed.
2. Why design in full scale?
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If a full-scale model can be built and visualized,
designers can discover from the model whether a
doorway is too large, an access space is too limited,
or a beam is not in the right position. If the full-scale
model is schematic and abstract in form, it will provoke
thinking and provide more clues about spatial
proportions, relationships among spaces, and
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possibilities
the primary design stage. In either of the cases, a
design product represented in a full-scale model would
enhance understanding of the design tremendously.
If a medium exists which would provide designers
with such an opportunity to interactively see design,
a sense of projection into the space and the design
will be created. Such a projection has the potential
to yield different perceptions, enriching the mind set
and diversifying the design processes. In the design
profession, this diversity will stretch personal vision,
enlighten mental images, and stimulate multidirectional
thinking 2,3 . All these are likely to improve design
quality. Furthermore, diversified media applied in
design will broaden thinking, change the design
process, and enhance creativity. Any design medium
that cultivates diversity implemented in full-scale
representation could be seen as an appropriate future
design tool.
Conventional design methodologies involve imagining
the form while conceiving design concepts threedimensionally in the mind, then revealing them
through sketching or modeling. The mental image in
this exercise is small in size and abstract in shape,
similar to those miniatures in Alice’s Wonderland. It
is thus questionable whether designers, after becoming
acquainted to the old convention, can open their
minds to accept change and adjust their mental
operations to see full-scale images. Especially, is it
necessary to transform the thumbnail mental image
into full scale for presenting it outwardly and then
simultaneously encode it back to memory for
designing? And how easy is it for designers to get the
entire picture of the design (building) while they are
at the moment in a remote corner of the building
(e.g., in a room at the end of a long corridor)? If,
however, there is a mechanism equipped with
dexterous zooming and navigation capacities,
designers likely would have no cognitive problems
between encoding, perception, and mental operation
— particularly rotation 4,5 . Then it would be possible
and worthwhile to do design in full scale.
3. How can one design in full scale?
Virtual Reality (VR), a very advanced human-computer
interaction tool 6,7 , provides a diversified medium for
visually, aurally, and interactively experiencing activities
Advanced VR tools applying Immersive Projection
Technology9 (IPT) could display objects in large scale
and would allow interaction between the user and
the environment. Coping with high-speed, real-time
image generation, a number of screen configurations
have been developed in the VR field, such as the
bench display10 and single-wall displays11 . Furthermore,
multi-wall displays, curved-screen displays, and CAVE12
displays also can generate advanced full-scale images.
Thus, combined with a design tool, it is feasible to do
design in a full-scale VR environment giving a fullscale sense of immersion, which helps individuals to
block out distraction and focus solely on the
information with which one wants to work. Effects
are similar to that of an audience and a theater
production. Only when the audience is immersed in
the theater will its attention focus on the actors’
performances. When it works, the theater has the
power to engage the audience and hold its attention.
This total concentration can convince, teach, and inspire. Particularly, the sense of vision overrides all other
sensory modalities in an immersive virtual
environment.
4. Applying virtual reality in design
Theoretically, a full-scale, navigable, and interactive
VR application has the potential of visualizing the
design products, diversifying perception, and
consequently enriching solutions. Design taught in this
fashion should be effective, and projects done in VR
in professional practice should also have great potential
for developing concepts, communicating ideas, and
presenting projects13 . However, perception in VR
space is direct and prompt, and therefore the
character of immersion would reduce the level of
abstraction and ambiguity for perception, which might
affect design thinking. Explained from a different point
of view, a design product is the outcome of a series
of cognitive mechanisms and activities. The full-scale
virtual reality environment, when used as a design
tool, is certain to change cognitive perception and
have an impact on design thinking.
4.1 Perception and representation
In cognitive science, perception is recognition. For
instance, the moment we see a friend, his or her face
triggers the image template of the face stored in our
memory, and the name associated with the template
is simultaneously recalled. Thus, we can address the
friend’s name immediately. This face template has an
image pattern stored in our memory, and a rapid
interpretation is activated after the cognitive
Design in a full-scale Immersive environment/Chiu Shui Chan/ ConVEACA
2001
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and behaviors conducted in cyberspace. Most VR facilities have the character of immersion, which is
created by perceiving images through three-dimensional visual devices8 . The perception in VR is similar
to projecting viewers into the environment. Applied
to design, its immersive and interactive nature enables
designers to perceive, grasp, and manipulate threedimensional building elements in a virtual space. By
implementing design in VR and seeing the design close
to reality, designers can immediately understand the
spatial qualities, visualize the color and texture of
materials, comprehend the major components of the
heating, ventilation, and air conditioning (HVAC)
system, experience the proportions of the spatial layout, and appreciate the aesthetic expression of the
structural elements. Therefore, it can be beneficial to
do design inside a VR environment.
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According to Anderson16 , our cognitive systems utilize
various pattern recognizers to structure sensory input
and to decode the message. Thus, it is assumed that
visual perception involves the following sequences of
processing information: (1) an object is first visualized,
then the sensory information is encoded into shortterm memory; (2) after the sensory information is
stored in short-term memory, it will be used as a
sensory code; (3) the cognitive processors proceed
by searching for the patterns stored in the long-term
memory to find a good match with the visual sensory
codes; (4) psychological attention is paid to recognize
the hidden patterns in the visual sensory codes and
starts the interpretation. Sometimes, the stored
1 1 or
0 image
0 1has1no1name
0 associated
1 0 0 with
0 it,1or a
pattern
name is saved but the associated image is not clear
or is missing. In either of these cases, the pattern
matching does not work and the search fails. Even
though the image patterns stored in memory and
the memory search methods (mainly by association)
utilized for recognition affect perception, the means
of representation of an image is really the key factor
for perception17 . Sometimes, what the eyes have seen
and what the mind believes can be two different things.
Whenever the visual information is uninterpretable
or misinterpreted, an illusion is produced. As there
are differences between the VR representation and
the
conventional
drawing-and-modeling
representation, the illusions created from each are
also different.
4.2 Illusion in conventional representation
Illusion is either caused by the failure to correctly
interpret information during the process of perceiving
a visual object, or by the misunderstandings upon
perceiving
the
representation. Sources
that can trigger illusion
are abstraction, ambiguity, and distortion that
exist in the representation of information. In design, illusion
sometimes can create
new sources for
thinking and for solution
generation. Thus, it is
important to explore
the differences between
the illusions that are generated from a conventional
representation and from an immersive VR
representation.
Abstraction. In the fine arts, quick sketches are always
simple and schematic, which would generate
abstraction and provide room for interpretation
(Figure 01). When a viewer sees a quick sketch,
various senses of uncertainty emerge and personal
interpretations are needed for comprehension.
Different persons perceive different abstractions from
one drawing and yield different interpretations.
Fig. 01. Sketches generate abstraction.
Design in a full-scale Immersive environment/Chiu Shui Chan/ ConVEACA
2001
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mechanism of pattern matching is executed. As such,
perception is to recognize, be aware of, or to
understand the message revealed in the
representation. Representation means to have
something standing in for something else and is the
means of symbolizing the things that happened in
reality14,15 . When perceiving objects in virtual reality,
viewers would fetch the hidden message based on
their experience and prior knowledge.
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but lower levels of reality.
Distortion. Special effects applied in perspective
drawing, such as punctuating colors, varying line
thickness, and switching drawing focus to cheat
perception, can overemphasize certain parts of the
form and create a distorted and surrealistic illusion.
As a result, viewers lose the sense of reality and
generate misinterpretation.
Distortion. In VR, similar results of switching focus
to create distortion might be possible by putting
different details on different parts of the model.
Particularly in IPT display, the three-dimensional space
inside an object may appear distorted, or viewers
may have difficulty with double vision or with blurred
images, which might distort attentions and generate
different interpretations. Therefore, distortion in VR
is different.
4.3 Illusion in VR representation
In VR, CAD modeling can be done on fast and
imprecise sketching, even though modeling tasks
usually require precision. Therefore, abstraction,
ambiguity, and distortion still exist in VR
representation, but have different characters and
dimensions.
Abstraction. In a VR environment, only three-dimensional objects exist, which are presented in some
reality. Abstraction of 3-D objects is suggested by
fewer details provided in the shape of the digital form.
If forms are simple and colors are primitive, they will
be perceived as having higher levels of abstraction
Ambiguity. In VR, digital models do not have the
luxury of allowing flexibility and ambiguity. Chances
for wild guesses and room for interpretation are rare.
Especially, applications requiring at-scale viewing are
very demanding and require a precisely scaled
presentation of the virtual object, whether it is an
automobile body or a human brain. However, in the
IPT display, there are cases when some objects were
seen to be inappropriately large or small, or they
appear at the wrong distance. Thus, there are different
types of ambiguity in VR.
In sum, conventional miniature models and drawings
provide clues to understand design concepts and
room for imagination. However, it is difficult to fully
perceive interior spaces and their spatial proportions
inside the building. In full-scale immersive VR, the digital
models could be as true as the reality, which would
reduce chances of generating conventional illusion
from ambiguity, abstraction, and distortion. On the
other hand, in comparison with the traditional
representations, VR representation might create a new
dimension of perception. Then, what are the new
illusions? How will illusions in VR affect thinking and
the implementation of CAD in full-scale VR? These
Design in a full-scale Immersive environment/Chiu Shui Chan/ ConVEACA
2001
Fig. 02. Louis Kahn’s sketch of
central Philadelphia.
Ambiguity. Different types of
lines utilized in a drawing suggest
different levels of accuracy. A
thick-line drawing is less precise
and more subject to a viewer’s
interpretation ( Louis Kahn’s sketch of central Philadelphia shown
in Figure 02). On the other hand,
working drawings are more
accurately drawn with fine and
straight lines joined precisely; the
level of ambiguity is minimized and
the flexibility for interpretation is limited.
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Design in a full-scale Immersive environment/Chiu Shui Chan/ ConVEACA
2001
serve the purposes of exploring design in full-scale
VR environment.
5. Design in full-scale VR
VR, with its immersive and interactive capabilities,
allows digital models to be constructed at a greatly
reduced cost. However, most current VR
environments18,19,20,21 for architectural design are either
primitive or require external modeling packages to
get a good visual exploration. For instance, it is
necessary to use computer modeling packages such
as Softimage or MultiGen to complete a building
model before it is imported to and displayed in the
VR environment. When mistakes are found in the
model while exploring it in the virtual environment,
corrections cannot be made immediately.
Modifications have to be done off line once the
exploration is completed. This method limits the
flexibility and plasticity of its application to the
schematic design stage, and is good only for using VR
technology as a production tool instead of as a
generative tool.
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newly generated design with an older version simply
by reloading a database. The lack of immediate
interaction and feedback may cause visual perception
errors while modifying the design in a more traditional
modeling package. Further, the user may not recall
the exact design flaw observed in the virtual setting.
On the other hand, a design cannot be done in VR
without having tools available. If there are building
materials and modeling operators handy in the VR
space, designers can simply select and build rather
than having to construct the model elsewhere.
Therefore, an on line computer model and methods
of saving design data are needed. This is the idea of
building a CAD system in the VR to help design22,23,24 .
A number of researchers are working on producing
a virtual walkthrough space to build 3-D shapes25,26,27 .
Chu et al. had built a multi-modal VR-CAD system28
which can be used at a Virtual Table driven by data
gloves. Their efforts focused on the algorithms and
techniques required for shape construction, placement,
and interaction.
To develop an appropriate design tool in VR, efforts
must concentrate on exploring means to simulate an
environment for users to do modeling with a userfriendly interface. Following this line of thought, a VR
design tool is developed to: (1) enable designers to
create a three-dimensional digital model and to
experience 3-D design at the early, primitive design
stage, (2) facilitate the evaluation of design decisions
made much earlier than conventional design methods,
and (3) create a more transparent tool for a virtual
perception of the creative processes. This VR design
tool is termed Virtual Architectural Design Tool
(VADeT).
6. VADeT system
VADeT was developed to explore the advantages
and disadvantages of using full-scale VR for design,
which is an application in C229 . C2, a synthetic virtual
reality facility, is a 12-foot by 12-foot by 9-foot cube
where high-speed graphics computers render images
which are back-projected onto the forward screen
and two lateral sides. A projector mounted above
the C2 projects the fourth image onto the floor. The
back side of the C2 is open. The four-display system
of the C2 uses LCD shutter glasses for the
stereoscopic display and electromagnetic sensors for
head and hand tracking. The C2 is controlled by two
Fig. 03-04. VADeT initial
environment and the main
tool palette.
6.1. Tool functions
VADeT utilizes the same set of the C2 input devices
to enable the direct manipulation of objects and an
immediate stereoscopic display of the effect of users’
actions. Furthermore, the VADeT system can also
be used in an n-Vision head-mounted display equipped
with the same tracking and input devices as the C2.
Whenever the system starts, it presents users with
an empty space delimited by a floor, a 3-D grid
(Figure 03), and a set of icons representing design
tools (Figure 04). Users can select a desired icon from
the menu for form generation, modify the new object
to fit its real dimensions, and then place it on the
right position.
Five major groups of design tools are provided as the
tool palette: entity30 creation, editing, color and
texture, storage and retrieval, and recording of the
design processes. The hierarchy of menu selection is
of standard tree structure. The five major tool groups
are installed on the root level. Each associated
submenu will be activated once it is selected. In the
following, the five major groups are explained briefly.
In this paper, the term «entity» represents geometric
objects.
6.2. Entity creation and placement
The entity creation group is marked as the «make»
option in the tool palette, which allows users to
interactively select a basic entity and place it in the 3D space. Users can select and place as many entities
as they desire (within system memory constraints).
Numerous entities can be grouped into one entity
and the modifications made will be propagated to
the entire group. The main coordinate axes for the
space creation are located in the scene of the C2.
Design in a full-scale Immersive environment/Chiu Shui Chan/ ConVEACA
2001
In C2, users are surrounded
by three-dimensional images,
projected in real time. Users
can interact with the C2 by
controlling a wand, which
feeds back to the graphics
computer. Not only an
immersive and interactive
setting but also a full-scale
space for projection and
perception, the C2 provides
the facilities to implement the
VADeT tool. Thus, running in
C2, this
VADeT
system has
a number
of metaphorical
icons symbolizing
tools for
selection.
Tools are available for defining materials, colors, and
hierarchical 3-D solid modeling operations can build
up, take away, and edit an electronic building.
1 C2 is an advanced version of the CAVE facility. In
the fall of 2001, C2 is upgrading to C4.
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Silicon Graphics (SGI) 12-processor Power Onyx
mainframes, each of which features two Infinite Reality
graphics engines. A 3-D audio system provides
localized sound.
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6.3. Entity editing
After entities are created in the virtual space, designers
can modify their location and size by applying the
translate, rotate, and scale operators. Because of the
speed of the real-time computation, accurate
placement of objects in 3-D space is not an easy task,
and three modes designed particularly for translation,
rotation, and scale are further developed. The mode
of free motion translates objects in any distance, and
designers can quickly place the entity at an
approximate location. The second mode of binding
allows designers to put constraints on how the
transformations apply to the entity. For instance,
translations and rotations can be restricted to only
1 1axis0under
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one
a certain
mode is the «snap-to-grid-and-angle» constraint,
which sets the granularity of the grid and angles for
accurately revising the dimensions and orientation.
These functions will fulfill the requirement of accuracy
in digital modeling. Entities also can be copied, cut
and pasted, and deleted in much the same way as the
utilities applied in most of the CAD systems. During
the operation of these functions, a clipboard is
implemented, serving as a memory buffer to
temporarily store the entities and their attributes.
6.4. Color and textures
Colors and textures are unique elements in design.
Decisions about particular colors and textures are
determined by the
designer’s
personal
preference,
design
knowledge, and aesthetic
appreciation. Currently,
the system treats these
aspects as informational
issues. Thus, several tools
have been developed to
serve as information
resources for decision
making. One tool is the
color palette 31 (Figure
06). This palette uses an HSV and RGB color mode
to obtain the right color schemes for objects. The
second tool is a texture palette (Figure 07), which
has fundamental building materials for major structural
components. Designers can assign and reassign any
color or texture to the generated objects.
Fig. 05. Shape selection
palette.
Design in a full-scale Immersive environment/Chiu Shui Chan/ ConVEACA
2001
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The coordinate axis arrows are attached to the wand
position. The current VADeT system provides 11
predefined primitive solid entities of box, cylinder,
torus, wedge, sphere, pyramid, and cone (Figure 05).
Several entities represent building structural elements,
for instance, box of wall and beam, torus of arch,
cylinder of column, etc.
6.5. Model navigation, storage, and retrieval
Objects existing in a full-scale model are large
compared to a
human scale. It is
not easy for
designers to move
a large entity
quickly within the
design space 32 in
VR or in reality.
Thus, a navigation
tool is provided to
Fig. 06
6.6. Recording the design process
The series of design actions is capable of being
recorded in the order the actions are performed in
the system. This is similar to achieving the
goal of «undo» and «redo» operations.
Because design is a creative process, it is
very likely that designers would change their
minds as the design evolves. It also serves
the goal of making VADeT not only a design
tool, but also a teaching tool. For instance,
saving the design actions of a master
architect provides students with valuable
data to learn what design methodology is used, how
the different entities are combined, why a design
action is creative, and what steps lead to achieve such
a creative level.
6.7. Heads-up display
During the design process, information about the
actual dimensions of the selected entities or the
parameters of the operators in use might be needed
as visual and memory aids for perception purposes.
Therefore, a heads-up display feature is implemented
that displays the status, parameters, and attributes of
the user’s immediate actions. Figure 08 shows an
example of heads-up display during a translation
operation.
6.8. VADeT implementation and its system
architecture
VADeT has been designed using an object-oriented
approach, focusing on supporting interactive performance, incremental development, extendibility and
display interface independency. A set of C++ classes
comprises the main core of the system. Three main
classes are defined to correspond to the main
components that constitute the system: the
environment class, the palette class, and the shape
class.
The environment class is the top-level class, which
contains all the member functions required to control the execution of a VADeT session. It includes
member functions to build the model, process a user’s
actions, and coordinate the communication between
the palette and the shape classes. The system design
Design in a full-scale Immersive environment/Chiu Shui Chan/ ConVEACA
2001
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Fig. 07. Color palette and
texture palette.
Fig. 08. Heads-up display
showing the operation of
translation
let designers easily move inside or outside the building or to new locations within the virtual space. One
of the key features of VADeT is the ability to save
the design at any time during the interactive session.
The saved
design can
be retrieved
for future
visits. The
purpose is
to allow the
e n t i r e
d e s i g n
process to
be done
within the
virtual
environment. Currently, VADeT stores the model
and all attributes in a custom file format. Other popular model formats, i.e., VRML, DXF, and FLT, will
be considered in the future to achieve compatibility
for importing and exporting models between VADeT
and other tools.
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Design in a full-scale Immersive environment/Chiu Shui Chan/ ConVEACA
2001
environments in C2 as well as in the head-mounted
display are fully immersive. The C2 software library
abstracts the implementation and configuration of the
VR devices, providing flexibility in adding new
immersive devices to be used in the VADeT system.
The palette class is the parent of two subclasses: the
input palette and the picking palette. The input palette
class is for objects that allow user input, such as the
color palette. The picking palette class is used for
objects where only optional selections are allowed,
such as the main tool palette (Figure 03).
The shape classes maintain all the different entities
supported by the system. These classes keep shape
attributes such as location, orientation, color, and
texture, as well as the shape modification history. The
shapelist classes store a «clipboard» which is used to
perform cut, copy, and paste operations. The control and synchronization of the C2 and the headmounted display are handled by the C2 software
library; its discussion is beyond the scope of this paper.
7. Evaluation of full-scale designing
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Features of the VADeT include capabilities to perform
solid modeling with a variety of solid primitives and
editing operations. This tool system provides several
traditional and new functions. The traditional functions
include the creation, placement, scaling, coloring, and
texturing of design primitives. The new functions
include navigation inside the model, saving the design
process, and redisplaying the design process. At the
present time, though this system does not have
Boolean operators installed to perform high-level form
manipulation, it is equipped with adequate functions
for form generation. In order to test the performance ability, two design experiments were conducted
for evaluation.
Two subjects were asked to
participate in the study by
completing a simple kitchen
design using the VADeT
system in the C2. Design
results were not required as
conventional drawings, but as
a full-scale digital model of a
kitchen. Walls, windows, and
appliances were created for
completing the design
problem. There was no time
limitation; however, the
subjects were asked to think aloud, and the entire
design processes were audio- and video-recorded for
data analysis. This technique is similar to applying
protocol analysis as an experimental and exploration
tool to study design problem solving33 and individual
style34,35 . The given design problem is the following.
«The owner will provide $250,000 to build a new home
with four bedrooms and a three-door garage in Ames,
Iowa. The site has not been selected and decided yet,
but the client would like a schematic design of the new
kitchen first. There are several design constraints — the
client requires views and reduction of street noise as
much as possible. The whole family enjoys a colorful
appearance and well-made materials. Please determine the size of the kitchen, dimensions of each appliance,
possible circulation, and the orientation needed for this
kitchen. The north of the site is directly in front of you.
Please start your design now.»
Fig. 09
1100111010001
Five characteristics
are found in the
design processes of
subject A. These
characteristics
suggest
the
influence of fullscale perception on
design thinking.
Fig. 12.
Diagram of the
floor plan.
•
The subject did not utilize or pay attention
to any particular dimensions of the generated
objects. Objects were created by using other
objects as reference of scale. Therefore, after
an object was generated, the subject had to make
extra efforts to adjust the sizes of the object, or
its adjacent objects, and the spatial relations
between them. This relates to the location, size,
and scale of the connected objects as a group,
because the subject could perceive
instantaneously the proportion of the object and
its surrounding space. Since perceived visual
distortion could not be tolerated, adjustment
occurred immediately.
• Materials or textures were assigned
immediately after an object was created to
solidify its existence.
• The subject spent little time formulating the
design problem. This may have been caused by
the immediate psychological projection into the
environment; the subject may not have had time
to analyze the problem.
• The entire process seemed more intuitive
rather than deliberate. One theory is that
because the perception is full of 3-D images,
the thinking process tends to be driven mainly
by geometric (visual) thinking instead of
conventional logical reasoning.
• The size of the kitchen is close to the
dimensions of the C2 setting of 12' by 12' by 9'.
Design in a full-scale Immersive environment/Chiu Shui Chan/ ConVEACA
2001
Fig. 10-11.
Three-dimensional view of the
design results
completed by
the subject A.
The subject A had been working for an architectural
firm in CAD for three years before this experiment
was conducted
and had applied
VR for his diploma project.
He spent a
half-hour
familiarizing
himself with the
s y s t e m
operations and
75 minutes to
complete the design, for which the floor plan is shown
in Figure 09. The subject indicated that no particular
concept or image existed in his mind before starting
the design. His entire design used the primitive
geometry provided by the system. The sequence of
design generation was diagrammed as shown in the
right-hand column of Figure 12. The alphabetical order
symbolizes the chronological order of form
generation.
0 1 0 0 1 1 0 0 1 1 1 0 1 0 0 0 1
7. 1. Experiment A
01001100111010
47
48
1100111010001
The subject indicated that immediately after he read
the design task, he had a solution which was in the
form of a U shape with a snack bar eating area in the
middle, and bay window on the south side for dining.
The rest of the kitchen was generated intuitively and
conceptualized in real time to find out things that
1 1 0
0 1for 1each1other.
0 1Therefore,
0 0 the
0 design
1
worked
the best
started from constructing the counters and cabinets
to form the U shape and proceeded to the counter
island in the middle. Others were thought out
instantaneously.
Several characteristics appeared in the process of
design session B.
• Most of the time, the subject applied the
snap function with a quarter-inch spacing interval
to move entities to the right location as well as
to scale objects up or down to get the correct
size.
Fig. 13. Three-dimensional view of the design
results by subject B.
The subject B was a senior architecture student at
the time this experiment was conducted. He also had
applied VR techniques to finish his diploma project.
The total time needed to finish the design was 3 hours
and 12 minutes. Results of 3-D images are shown in
Figures 13, 14, and 15, and plan view is shown in
Figure 16. The design solutions are to locate the
kitchen facing north, to have the south side leading
to the dining area, with bay windows on the facade
for exposure to southern light. The counter island
provides a snack bar function with views through the
south (Figure 14). The chosen materials are marble
finishes for the countertop, ceramic tiles for the island
countertop, and stylish designs for chairs to address
the requirements of well-made materials.
• The subject applied color and materials to
all entities.
• The entities were mostly created on the
side, then moved and
placed on the right
location afterwards.
• The
subject
considered the rule of
the kitchen triangle36 in
the process.
Fig. 14.Section
perspective of the design
results by subject B.
• No alternative design solutions
were created or considered, and
the whole process was linear.
• The subject spent a lot of
attention on the proportions of
each object, their spatial relationships with
adjacent objects, and their location in the space
that fulfilled functional links with other objects.
• The subject used his body as a reference
scale; for instance, he utilized the height of his
hip and the length of his palm to measure the
height of the counter and the size of the cabinets’
handles.
1 Kitchen triangle is a design convention to reduce circulation conflict in the kitchen operations.
Metaphorically speaking, lines joining these three
elements of sink, range, and refrigerator form
the known «work triangle.» According to
Neufert (see Neufert, E Architects’ Data Crosby
Fig. 15. Three-dimensional top view of
the design results by subject B.
Design in a full-scale Immersive environment/Chiu Shui Chan/ ConVEACA
2001
0 1 0 0
7.2. Experiment B
Fig. 16. Diagram of the
floor plan.
One limitation of VADeT found from the experiments
relates to the availability of needed functions or
commands. For example, at the time, the system could
not generate organic forms due to not being able to
efficiently run Boolean operations. Another example
was found on experiment B; when the experimenter
asked for the rationale of placing the refrigerator next
to the stove, the subject reported that he had
considered moving the refrigerator to a different
location but eventually left the refrigerator in the original spot. It was because the system, at the time, did
not have an efficient «group» function to allow moving
multiple objects
simultaneously, and it
was a tedious process
to move objects one
by one. Thus, any
CAD system must
provide necessary capacities to fit design purposes.
The small samples of experiments yielded interesting
observations about designing in a full-scale VR
environment. Of course, it is risky to jump to the
conclusion or to claim that the observations are really
representing the design activities of all designers.
However, it is worthwhile to report the findings so
far.
• Quite often, subjects checked the function
of circulation of each generated objects in the
entire process. Particularly, there are no
approximations in determining the fluidity of
circulation on walkways and structural
components of objects. The VR environment
provides a real-time test for the functionality,
which might limit the generation of alternative
solutions and sets up a linear thinking process.
• Design products were generated mostly by
the visualization and manipulation of the objects.
Both subjects were preoccupied with completing
the color and texture of the objects, and
arranging and sizing them to show their
existence. This suggested that the VR products
contained a higher level of specification than the
traditional design method. Designers not only
concentrate on spatial relationship, but also on
the texture, color, and material. Thus, visual
illusion in VR is different, ambiguity and
abstraction in VR are less significant due to the
immersive nature of this design tool. Because of
this, VR representation is a new instrument for
understanding virtual aesthetics.
• A full-scale model, however, also limits
immediate perception of the entire site and its
adjacent context and presents problems for
immediately comprehending relationships among
objects macro-wide. This is similar to the fact
that a designer has difficulty perceiving the scene
of a city block while he or she is on the street
level or inside the building. Such limitations may
constrain the immediate response of reflection
projected between the designer and the design
status, and may block the spring of immediate
intuition.
Design in a full-scale Immersive environment/Chiu Shui Chan/ ConVEACA
2001
8. Observations
0 1 0 0 1 1 0 0 1 1 1 0 1 0 0 0 1
Lockweed Staples, London (1980) pp 54-56), the
distance between sink and range should not exceed
1.8 meters (5'-10") and the total of the three triangles
sides should be between 5.5 meters (18'-4") and 6
meters (19'-8").
01001100111010
49
50
1100111010001
Design in a full-scale Immersive environment/Chiu Shui Chan/ ConVEACA
2001
Thus, in the schematic design stage for concept
generation, the best solution is to control the scale
mechanisms. In other words, a small scale should be
used to build large objects and to view exteriors, and
then the designer should navigate inside the structure
to explore the interior in full scale after the overall
form is generated.
9. Discussions
VADeT provides a chance to explore design in full
scale. Navigating through spaces in VADeT is quick,
and the change of perspective is very mobile. Objects
can be generated, copied, deleted, moved, scaled, or
regenerated in real size without difficulty. The whole
process can be saved, re-entered, and remodified.
These unique characteristics provide a greater degree
of flexibility for designing than traditional sketch-andmodel methods. Regardless of the level of
sophistication and the modeling functions that have
been achieved, this system can be seen as a threedimensional sketching tool.
0 1 0 0 Experiments
1 1 0 0conducted
1 1 1 in0this1study
0 0documented
0 1
how a full-scale design tool affected design processes
and representations. The flexibility to change the
location, size, and attributes of each object and
visualize changes immediately is very beneficial for
schematic design and parti design1 . It also has great
potential for teaching design, because the cause and
effect of any design movement made is clearly
displayed. However, both subjects in the experiments
used their bodies as references to determine the size
of the objects. Thus, a higher level of precision in
scaling was expected when designers were in the VR
environment. Precision reduces conventional
ambiguity, which may occur rarely while perceiving
in VR space. The new illusion in VR is generated mainly
by the interaction within the environment, particularly
motion. In other words, virtual illusion relates to the
rapid change of composition perceived from the rapid
change of perspective angles. Thus, illusions in drawing
perception are one-shot-and-still illusions, but in VR
they are jumping-and-continuously-generated illusions.
This is a new experience for users, and it is difficult to
find verbal data to prove the theory.
On the other hand, in order to get a quick and
imprecise sketch to yield room for thinking, precision
must be sacrificed, and the effects and methods of
sketching in VR, in all, is a new research frontier. This
relates to what Gombrich38 had mentioned, that the
language of art is not that it enables the artist to create
the illusion of reality, but to give the illusion of looking
into the invisible realms of the artist’s mind. Because
perception in VR switches from visualizing still images
to moving images, from imprecision to precision, from
abstraction to reality, from image distortion to
distorted attention, the definition of aesthetics in reality
may need to be redefined in the future. As Read39
wrote, «We do not always realize that the theory of
perspective developed in the 15th century is a scientific
convention; it is merely one way of describing space
and has no absolute validity.» This applies to the
immersive VR representation.
It also is interesting to observe the different design
processes emerging from this full-scale tool.
Apparently, the sense of projection and immersion is
quite convincing, which alters the design behavior.
The design process is almost purely visual. The
overwhelming sense of the projection and immersion
diverts designers’ attention to local details and causes
10. CONCLUSIONS
Virtual reality is a new technology allowing
users to step through the computer screen into a
3-D artificial world. To further design in the artificial
world, users should be able to manipulate objects
naturally in the virtual space with their eyes, feet,
and hands. To this end, new methods of modeling
architectural objects directly in VR need to be
further explored — especially the freedom of
deformation and the Boolean operators required
to make organic forms. This will make the object
generation processes more sculpturally oriented.
The recording and redisplay capabilities of VADeT
characterize its use as a tool for observing
designers’ thinking process to understand how a
full-scale representation would affect design
thinking. Given the opportunity to visualize the
design process in VR, viewers will be able to
understand the myth of how master architects
perform their creative works. In summary, design
can be done in full scale by applying VR technology.
With digital models displayed in different
geographical locations, designers would learn
various design principles, methods, and processes
inherited in various design cultures. This would
transcend geographical boundaries to allow
architectural design to be taught, learned, seen, and
touched from different locations to improve
thinking.
ACKNOWLEDGMENTS
This project resulted from a collaborative effort.
The research was funded by the Special Research
Initiation Grant and a Second Discipline Grant. The
implementation was done by Lewis Hill, supported
by the Research Careers for Minority Scholars
Program and assisted by Professor Carolina CruzNeira. Special thanks should go to the subjects
involved in the design experiments. Without their
participation, this project would have been
impossible. Parts of the thoughts were presented to
CAADRIA99 and the 4th Design Thinking Research
Symposium, hosted by MIT
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Design in a full-scale Immersive environment/Chiu Shui Chan/ ConVEACA
2001
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Design in a full-scale Immersive environment/Chiu Shui Chan/ ConVEACA
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36 Kitchen triangle is a design convention to
reduce circulation conflict in the kitchen operations.
Metaphorically speaking, lines joining these three
elements of sink, range, and refrigerator
form the known «work triangle.» According to
Neufert (see Neufert, E Architects’ Data
Crosby Lockweed Staples, London (1980) pp 5456), the distance between sink and range
01001100111010
53