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11
Smart-Phone Augmented Reality for Public Participation
in Urban Planning
M. Allen
Information Science
University of Otago
Dunedin, New Zealand
allma658@student.otago.ac.nz
H. Regenbrecht
Information Science
University of Otago
Dunedin, New Zealand
holger@infoscience.otago.ac.nz
M. Abbott
Applied Sciences
University of Otago
Dunedin, New Zealand
mick.abbott@otago.ac.nz
ABSTRACT
We investigate smart-phone based augmented reality
architecture as a tool for aiding public participation in
urban planning. A smart-phone prototype system was
developed which showed 3D virtual representations of
proposed architectural designs visualised on top of
existing real-world architecture, with an appropriate
interface to accommodate user actions and basic
feedback. Members of the public participated in a user
study where they used the prototype system as part of a
simulated urban planning event. The prototype system
demonstrated a new application of augmented reality
architecture and an accessible way for members of the
public to participate in urban planning projects.
Author Keywords
Smart phone, architecture, urban planning, participation,
augmented reality, mobile augmented reality
ACM Classification Keywords
H.5.1 Multimedia Information Systems, H.5.2 User
Interfaces.
INTRODUCTION
Citizens show “rational ignorance” toward urban
planning events (Krek, 2005). The cost of learning how to
participate in urban planning projects outweighs their
perceived potential benefit from taking part (Krek, 2005).
How might we help reduce the cost of learning, and
improve the public's perceived benefit from taking part?
How can we increase their willingness to participate?
It can be seen from the literature that augmented reality
can be used to help enhance the urban planning process
(Piekarski and Thomas, 2001; Sareika and Schmalstieg,
2007; Schall et al., 2009). However, the emphasis of
research in the field of mobile augmented reality for
urban planning is with adding extra functionality to create
novel yet applicable systems for expert users and
stakeholders, and little has been done in the way of public
participation systems for average users (Zhou et al.,
2008). As Livingston (2005) suggests, these added
functionalities tend to confound the user's experience and
ability to perform tasks. There is a need to evaluate high
level user tasks such as information identification and
representation, as most of the focus in the field is in low-
level perceptual tasks (Azuma et al., 2001; Livingston,
2005). Similarly, more work has been done in developing
the enabling technologies of augmented reality, like
tracking, calibration, and display, than to the areas of
mobile augmented reality and augmented reality
application evaluation (Zhou et al., 2008).
The prototype we’ve developed is a smart-phone-based
augmented reality system for supporting public
participation in urban planning events. It takes into
account the potentially confounding factors from previous
research which could hinder public participation and limit
the ability for users to evaluate the system's potential
benefits. This study used mobile augmented reality to
show 3D models of potential new designs of a building
within the context of its environment. This was done in
the context of public participatory urban planning, and the
system allowed its users to vote for their preference in the
proposed designs. These votes would be made available
to the managers and stakeholders of the urban planning
event.
The objective of this study is to determine whether by
using a smart-phone augmented reality system both (1)
the willingness of the public to participate and (2) the
perceived participation in urban planning is increased. A
secondary objective of this study is to qualitatively
examine the public reaction to this technology. This study
not only provides insight into the possible application of
smart-phone augmented reality for urban planning
projects, but also provides a better understanding of the
general public's perception and experiences using a
smart-phone based augmented reality system.
This paper will briefly traverse the previous work done in
the area of mobile augmented reality for urban planning,
and go on to describe the developed prototype system,
the research methodology and results and analysis of the
obtained data. The results of the research are discussed,
and possible future work is considered.
PREVIOUS RESEARCH
Public participatory geographic information systems have
been used in the past to try and improve the public's
participation in urban planning processes, but little
empirical evidence exists to show its success (Krek,
2005). In fact, the effect of “rational ignorance” can be
observed among citizens, where the cost of learning how
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to participate in the planning process can outweigh their
perceived potential benefit; the perceived benefit from
participating is usually low and the cost of learning how
to use a new system and participate in the process is high
(Krek, 2005).
Visual information is used for a citizen to understand and
act upon the changes proposed in an urban environment
(Wang, 2007). Such visual information can be retrieved
from a variety of sources, including from original 3D
architectural models produced using modelling software,
such as CAD drawings (Wang, 2007). By allowing access
to this kind of easily interpretable visual information, the
non-professionalism barrier can be suppressed (Hanzl,
2007). Among the various information technology tools
available for public participation in urban planning is
augmented reality.
Augmented Reality
Augmented Reality (AR) “allows the user to see the real
world, with virtual objects superimposed upon or
composited with the real world. Therefore AR
supplements reality” (Azuma, 1997). AR can be defined
as having three main characteristics: It combines real and
virtual elements, in interactive real-time, which are
registered in 3-D. There are many enabling technologies
that are required to make useful and compelling AR
applications, including display devices, tracking
technology, calibration techniques, and interfaces and
visualisation (Azuma, 1997).
Mobile Augmented Reality and Urban Planning
Mobile augmented reality provides a new way to
approach outdoor information tasks. This section
describes three major efforts to develop outdoor
augmented reality urban planning systems: Tinmith-
Metro, Urban Sketcher, and Vidente.
Tinmith-Metro
In (Piekarski et al., 2001; Thomas, Piekarski, and
Gunther, 1999) the Tinmith-Metro mobile augmented
reality platform was developed to examine possible
answers to the question: “How does one visualise a
design for a building, modification to a building, or
extension to an existing building relative to its physical
surroundings?” They suggest that in the past a customer
or stakeholder in the design process would need to be in
the design studio to propose changes to a Computer
Aided Design built 3D model, viewed on a graphics
workstation. Piekarski et al. used augmented reality to
allow the visualisation of designed buildings, or building
extensions and modifications, to be displayed and viewed
by the user in the real environment where the target end-
users were architects, designers, engineers and clients.
The system uses a wearable computer in conjunction with
a see-through optical head mounted display to allow the
user freedom of movement to interact with and view their
environment. The system used GPS and an electronic
compass to perform object tracking and registration. A
miniature keyboard was used to provide user input and
facilitate interaction with the system (Piekarski et al.,
2001).
They concluded that their system provided users with a
sense of space and “feeling” for the size and location of
the virtual objects.
While the Tinmith system provides a comprehensive set
of functionalities for viewing and manipulating
augmented 3D architecture it was (a) not designed to
allow for a degree of realism suitable for a general, public
audience and (b) requires substantial instrumentation of
the user.
Urban Sketcher
As part of the broader IPCity research project, Sareika
and Schmalstieg (2007) developed the Urban Sketcher
application to “encourage and improve communication on
urban design among stakeholders.” The system provides
multi-modal interface devices for interaction and
collaboration among many users. Visual feedback is
provided on a single projected display containing live
footage of the augmented scene. The system is housed in
a tent on site at the planning event and allows for
conventional planning activities as well as the mixed
reality approach.
With the Urban Sketcher application, users can directly
alter the real scene by sketching 2D images which are
then applied to the 3D surfaces of the augmented scene.
This sketching provides an intuitive method for
collaboration and interaction, even for inexperienced
people.
Urban Sketcher demonstrated that the use of AR
technology is suitable for public participation. However,
it requires a substantial instrumentation of the
environment.
Vidente
Schall, Mendez et al. (2009) developed a mobile AR
system to provide an alternative to traditional printed
plans for field work carried out by utility companies.
Using customised hand-held devices, Vidente has been
developed, tested and evaluated for demonstrating
underground infrastructure virtualisation in the field.
Features and abstract attributes of a geographic
information system (GIS) were transcoded into 3D scenes
via a multi-stage pipeline. GIS features were converted to
Geography Mark-up Language, annotated using real-time
data uploaded from the device in the field, and visualised
on the device using a 3D rendering engine. The
visualisation could have filters applied to reduce the
amount of information on screen (Schall, Mendez et al.,
2009).
Vidente incorporates various spatial interaction tools. An
excavation tool overlays hidden underground
infrastructure on top of real-world objects. A labelling
tool visualises meta-information from the original GIS on
objects selected with a cross-hair. A filtering tool
removes unwanted clutter from the visualisation (a
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feature which proved to be too complicated to use, so the
system was reduced to a selectable set of predefined 3D
features.
The hardware used was an ultra-mobile PC implementing
a version of Studierstube (Schmalstieg et al., 2002), a
GPS antenna and a camera, housed in a custom-made
base with handles. Three factors were recognised for a
system of practical value: it must have sufficient
computing power, it must be ergonomic, and it must have
six degrees of freedom (i.e. able to be moved in the three
perpendicular axes, along with pitch, yaw, and roll
rotations) (Schall, Mendez et al., 2009).
RESEARCH FOCUS
It can be seen from these major studies that the
technology used in the designed systems, such as head
mounted displays, wearable computers, and stationary
tools within a tent, while providing appropriate
accessibility and functionality to select stakeholders at
prearranged meetings, are not likely to be as accessible to
the public as other possible platforms such as smart-
phones. Smart-phones are becoming an increasingly used
platform for augmented reality (Wagner and Schmalstieg,
2009) and based on the increasing sale figures, the
popularity of smart-phones is increasing (Wagner, 2009).
This research focussed on using smart phones and
augmented reality to provide the general public with an
accessible and user friendly way to participate in urban
planning events. With our prototype system, users would
be able to view new urban designs accurately in the
context of their environment, reducing the non-
professionalism barrier, and increasing the proliferation
and potential of better informed feedback from members
of the public.
Compared with the previous augmented reality urban
planning case studies mentioned in this paper, our
prototype system would seek to give anybody with access
to a smart phone the ability to participate in urban
planning events, in their own time, and without the need
to attend formal or prearranged meetings or presentations.
It would serve as a front end to the urban development
process, allowing members of the public to view easily
interpretable augmented reality visualisations of proposed
urban developments, and to conveniently provide
feedback to event organisers.
Hypotheses
Hypothesis One: The use of smart-phone augmented
reality in a public urban planning event increases public
willingness to participate in the urban planning process.
Hypothesis Two: The users of the proposed system are
satisfied with the level of their perceived participation in
the planning process.
Research variables
The independent variable of this study is the presence of
the proposed smart phone augmented reality system,
including its components.
The dependent variables of the study are:
• User perceived participation: the degree to which
users perceive that their contribution and
participation in the urban planning event is
significant towards the outcome of the event.
• User willingness to participate in urban planning
projects: the extent to which the user has been
willing, or is willing, to participate in urban planning
events.
The prototype mobile AR system
The system, as referred to in this article, consists of a
smart-phone and the software and content required for
performing the urban planning augmented reality
visualisation task used in this study. A graphical user
interface was implemented as the front end to the
StudierStubeES software (Schmalstieg and Wagner,
2007), an augmented reality platform for embedded
systems. The StudierStubeES (StbES) software provides
the augmented reality tracking and visualisation
framework that this project required. A panorama tracker
(Langlotz, 2011) was implemented as the tracking
method for the system, where the camera is used to sweep
the scene of interest, thereby creating a panoramic image
of the scene to which the visualisations are calibrated. A
requirement of this tracking method is that the user
remains stationary during system use. 3D architectural
models were designed by students of the DESI313
Environmental Design course at the University of Otago,
and used as the visualisation content of the system. A
heuristic evaluation of the system was performed to
assess its usability before being used in the field user
study.
Toshiba TG01 Smart-Phone
The Toshiba TG01 smart-phone was chosen for this
project. It has a 1GHz SnapDragon processor, 256 MB
RAM and 512 MB ROM, a large touch-screen, a camera
capable of taking reasonable quality stills and videos
(3.15 MP, 2048x1536 pixels, with autofocus; VGA video
at 30 frames per second), and its Windows Mobile 6.1
operating system is supported by the StbES framework.
System Content: 3D Architectural Models
The 3D architectural models had to be processed and
calibrated for use in the system. This required following a
strict process pipeline to successfully convert the models
from their original 3D Studio Max formats into the
Virtual Reality Mark-up Language format supported by
StbES conversion software, and also to realign the
models in virtual space to have them correctly aligned
with the real architecture.
Firstly, the models had to be loaded into the Deep
Exploration 3D model conversion software. Using this
software, each model could be repositioned and scaled in
order to overlay with the real architecture. These output
files were then converted to the StbES XML format using
the VRML To StbES Converter software. Finally, the
XML files could be added to the data directory of the
StbES application and viewed upon running the
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application. The working models were tested against a
scale model of the real architecture to be augmented
(Westpac building in Dunedin, see Figure 1).
Figure 1. Overlay on scale model
System Interface
The functionality of the system is limited to being able to
view the available 3D models and vote for the models
according to personal preference. The idea is to keep the
functionality to a minimum in order to limit any
confounding factors in the user experience of the system.
As such, the graphical user interface (GUI) had to
accommodate these functions in the most direct, user
friendly way possible. As depicted in Figure 2 only the
following functions have been implemented:
• a button to switch between the different virtual 3D
models (green, MODELS)
• a voting button switching on a row of “smiley”
buttons (yellow, VOTE)
• buttons to calibrate (operator) and exit the
application (red, EXIT, RESET)
Figure 2. The Graphical User Interface
Heuristic Evaluation of the User Interface
A heuristic evaluation was performed to discover
usability issues with the system and to determine what
changes would need to be made to reduce potentially
confounding interface issues before the final user study in
the field. Eight students from post-graduate Information
Science and Computer Science courses volunteered to
participate in the heuristic evaluation of the system. All
participants were experienced computer users and were
familiar with smart-phone technology. The number of
participants to take part in the heuristic evaluation was
suggested by Hwang and Salvendy (2010). The
participants recorded usability issues which violated
Nielsen's ten heuristics for usability design (Nielsen,
1994), and noted them as being one of four levels of
severity: critical, high, medium or low.
The problems discovered during the heuristic evaluation
were considered and amendments were made to the
system accordingly before its use in the field user study.
The changes made to the user interface can be seen
between Figure 1 and Figure 2.
USER STUDY AND METHODOLOGY
A user study was designed to formally record quantitative
and qualitative data from members of the public using the
system. The study took place on the opposite corner to
the Westpac building on George Street, Dunedin, NZ, in a
position where the panorama tracker could be calibrated
by the researcher to overlay the 3D models onto the
Westpac building.
Members of the public at the site were approached
without discrimination and individually asked to
participate in a brief research study. Upon agreeing to
participate, they were given an information sheet
regarding the research and the user study, and asked to
complete a consent form.
Each participant was initially asked a series of
demographic questions regarding their familiarity with
mobile devices and their applications, their previous
experiences with urban planning events, as well as basic
demographic information such as age and gender. All
questions of the questionnaire were asked in an interview
style by the researcher, where participants could respond
verbally. After completing the initial questionnaire,
participants had a simulated urban planning scenario
explained to them by the researcher, which they were told
was a fake event designed for the purposes of the
research.
The smart-phone system was then calibrated by the
researcher to overlay the visualisations correctly on the
Westpac building, and participants then used the system
in the context of the simulated urban planning event
(Figure 3).
Participants would toggle through and view each virtual
model as it would appear at the Westpac building site,
and voted on each of the proposed designs by selecting
the appropriate “smiley” vote button. They were asked a
series of questions about their experience when they had
finished using the system. The questions included 7-point
Likert-like scale responses and general feedback. The
questionnaire questions are described, along with the user
responses, in the results section of this paper. Upon
completing the study, participants were offered a small
chocolate bar as reward for their participation.
15
Figure 3. User’s View during study
Assumptions
It is assumed that in order for the study to have achieved
validity:
• participants in the user study are representative of the
general public
• the smart-phone system adequately demonstrates the
augmented reality technology in question
• participants will provide genuine, considered
responses to survey questions
• the questionnaire will adequately extract useful data
during the user study
• the urban planning scenario used is typical of usual
urban planning events
Potentially Limiting Factors
Participants
The participants who volunteer to participate in a field
survey may vary greatly, and these variations will affect
the outcome of the study. Their mood, level of technical
capability and familiarity with the technology, the amount
of free time they have, and other possible factors such as
age and gender and could affect their experience when
using the system.
The age and gender of each participant, as well as their
familiarity with cell phone and smart phone technology,
would be recorded as part of a demographic
questionnaire. Participants would be asked if they have
enough time to comfortably complete the survey.
Field conditions
During any single use of the system, field conditions may
change which could affect the quality of the augmented
reality tracking, and therefore potentially disrupt the
overlay effect. Care would be taken to ensure that the
panorama tracker was correctly calibrated before each
trial, and that the quality of the overlay was observed and
recorded during the trials.
Interface design
It is possible that the designed interface would not meet
satisfactory levels of usability by the time the field study
is scheduled to commence, or that the expert users of the
pilot study heuristic evaluations consider some aspects of
interface design to be acceptable where members of the
public may not. It was assumed that any further problems
would be observed during the user study, and could be
explained by the researcher where necessary.
Complexity of task
A basic requirement of using a smart phone based
augmented reality system is to understand, even vaguely,
the relationship between the technologies and how they
interact and operate. For instance, the phone camera
needs to be pointed at the augmented reality marker or
correct position of the panorama scene, either of which
needs to be kept in view for the visualisation to be
correctly rendered. The users' experience of the system
may largely be affected by their ability to quickly
understand these principles. This potentially confounding
variable is of course to be expected when introducing
members of the public to a new technology, and would be
managed and observed.
Questionnaire
No suitable questionnaire regarding people's willingness
and perceived participation was found for use in this
study. The questionnaire used was developed by the
researcher, and could be a potential confounding variable
in this study. There is the possibility that it could
introduce bias into the results.
RESULTS AND ANALYSIS
The demographic data were analysed first. 18 members of
the public participated in the field user study. Seven of
the participants were female and eleven were male. Ten
were aged between 18 and 25 and eight were 26 and
older. After initial analysis of the data, it was decided that
the results should be split into the aforementioned age
groups to determine whether age was a factor in the
results. The results from the quantitative aspects of the
questionnaire are shown below. “7” is always the positive
end of the scale, and “1” is the most negative possible
response. They are accompanied by descriptions of the
formal observations made by the researcher as well as the
verbal feedback from the subjects. The data analysis is
split into four categories: mobile device familiarity, user
experience, perceived participation and willingness to
participate.
16
Mobile Device Familiarity
It was found that subjects in general were less familiar
with touch-screen smart-phones than regular cell phones.
The 18-25 age group showed a higher level of familiarity
with smart-phone technology (mean=5.2, stdev=1.75)
than the 26-plus age group (mean=2.375, stdev=2.2). The
26-plus age group showed a greater difference in
familiarity between cell-phones and smart-phones.
Figure 4. Mobile device familiarity results for all
participants.
Figure 4 shows the responses from all subjects to these
first three questions of the questionnaire. The variance in
the results was quite large (3.04 and 4.87 for Question 1
and Question 2 respectively), so the median value for
these responses was used for comparison. This can be
seen in Figure 4 where the median value for cell-phone
familiarity was 6 and the median value for smart-phone
familiarity was 3.5. Although this comparison shows a
rather significant drop in the participant's familiarity with
smart-phones compared to cell-phones (Q1 mean=5.28,
stdev=1.74; Q2 mean=3.95, stdev=2.2; p=0.024), the
rather large range in the upper and lower quartiles of the
responses suggest the presence of some underlying
contributing factor to these responses. It was anticipated
that one possible factor was the age difference between
the participants, where it was assumed that the younger
participants would be more familiar with mobile device
technology. The following figures, Figure 5 and Figure 6,
show the responses from the 18-25 year old group and the
26-plus age group respectively.
Figure 5 shows a much closer level of familiarity with
cell-phones and smart-phones in the 18-25 year old age
group ('18-25' Q1 median=6, Q2 median=5.5) than the
overall response. Figure 6 shows that the 26-plus age
group are not only less familiar with cell-phones than the
18-25 age group, they were far less familiar still with
smart-phone technology and mobile device applications.
The median response to Q3, pertaining to the participants
familiarity with mobile device applications, was very low
on the Likert-scale (Q3 median=0.5).
Figure 5. Mobile device familiarity results for 18-25 age
group.
Figure 6. Mobile device familiarity results for 26+ age
group.
There was a clear gap in familiarity of mobile device
technology between the two age groups. It was
anticipated that this gap in familiarity would possibly be a
factor in the participant's responses to the user experience
questions as well as the questions relating to the
hypotheses. For that reason, the results of the remaining
questions were also split into the two age groups for
further comparison.
User Experience
The results of the user experience questions were also
split into the two age groups, 18 through 25, and 26 and
older. The feedback provided by the subjects for each
question give more insight into the Likert-scale
responses.
System Ease of Use
Question 6 (Figure 7) asked participants how easy they
found the system to use. The median response to the
question over all participant's was high (Q6 median=6)
although the range of values extended as low as 3 on the
seven-point Likert-scale. This can be explained when
looking at the responses of the age groups. The 18-25 age
17
group response was very positive (median=6, min=5),
whereas the median response from the 26-plus age group
was 2.5 points lower (median=4.5), and the minimum
value was lower still (min=2).
Figure 7. Perceived system ease of use.
The feedback provided some insight into these responses.
One user of the 26-plus age group found the screen to be
too small to use comfortably, and one person found the
buttons for voting to be too small. Most people found the
system easy to use because of its simplicity.
System Utility
Figure 8 shows the participants' responses when asked to
what degree they considered the system useful for
participating in the urban planning project. The results to
this question were more similar between age groups than
in previous questions. This could suggest that it did not
require a high level of familiarity of the technology to
understand the systems purpose and consider its potential
utility.
Figure 8. Perceived system utility
According to their feedback, participants thought that the
system was a useful visual aid which would motivate
people to get involved in the planning process, and that it
was good to have an actual perspective of how the
designs would look. One participant noted that it would
remove the shyness that people often experience in public
meetings (during traditional planning events), and that
everyone could participate. It was suggested that “multi-
voting” would need to be controlled, and that it should
have been available for previous planning processes.
Augmented Reality Architecture
Participants were asked how useful they found it to see
the new architectural designs superimposed in their actual
environmental context. Again, the response was very
positive and relatively even across the age groups. The
box plot of the results can be seen in Figure 9. Both the
overall response and the 18-25 group showed a median of
7, and no response was lower than 4 on the 7-point scale.
Figure 9. Perceived usefulness of seeing architectural
designs in their environmental context
Participants found the augmented reality visualisations
useful for a variety of reasons. It was suggested that it
would help people visualise the intention of the design
better than if they only had access to drawn plans, and
that it was good to see a real life model of how the
proposed buildings would look. One respondent noted
that they were unfamiliar with other methods of public
involvement in the design process, so was unsure how
these visualisations would compare to more traditional
methods. Some participants would have liked a better
view of the building and the overlaid model (a
shortcoming of the panorama tracking technique that was
to be expected), and one would have liked more realistic
models to fully understand how they would look in the
context of the street.
Perceived Participation
Only two participants had participated in previous urban
planning events, making it difficult to gauge any shift in
public response in terms of perceived participation.
Figure 10 shows the results of the question which asked
participants whether they felt that their feedback (in the
18
form of voting) as a result of using the system would be
considered and used by the organisers of the event during
the decision process. The feedback given by the
participants helped explain why the results were fairly
neutral, with a large range (between 6 and 2 on the
Likert-scale). It was suggested that the voting from the
system would only be a significant factor in determining
the outcome of the urban planning process if enough
people used the system and the results of the voting were
made public. A few of the users felt that the organisers
would not be likely to consider feedback from the public,
and that they were more interested in the views of
businesses. A few users appreciated the fact that there
were hidden but sensible processes in the planning
process that might not accommodate public input.
Figure 10. Perceived participation in the simulated urban
planning event
Willingness to Participate
Paired two-sample t-tests (with alpha value=0.05) were
performed to compare the values of means between the
questions relating to the hypothesis. The results of the t-
tests can be considered significant, that is, it is highly
likely that the difference in means between the two
populations did not occur by chance, if the p-value of the
test is less than 0.05. P-values between 0.05 and 0.1 can
be considered marginally significant (Utts and Heckard,
2005). The two-tailed t-test p-value was used in the
analysis of this data as the anticipated difference between
the means could be either positive or negative.
The result of the t-test performed on the “willingness”
questions (“How willing are you to participate in urban
development projects?” asked before using the system
and “To what degree would you be willing to participate
in urban development projects if you had personal access
to this type of system?” asked after using the system)
showed a significant increase in willingness recorded for
the second question. The mean increased from 4.33 (with
standard deviation = 1.74) to 5.33 (standard deviation =
1.71) with a p-value of 0.005 (t-critical=2.11, df=17).
This increase in mean can be seen in Figure 11. The
increase in mean for the 18-25 age group was significant
(Q1 mean=3.9, Q2 mean=5.7, p=0.001, t-crit=2.262,
df=9).
Figure 11. Mean willingness to participate without (Q5) and
with (Q9) the system
DISCUSSION
This research aimed to determine whether the public’s
willingness to participate in urban planning projects and
their perceived participation in such events would
increase if they had access to a smart-phone augmented
reality system. A prototype smart-phone augmented
reality system was designed and used to overlay virtual
3D architectural designs over an existing building and to
allow users to provide feedback based on their personal
preference of the proposed designs. A user study was
designed to evaluate the prototype system in the field,
using a custom questionnaire which members of the
public would complete. The intention was to gather
quantitative data in order to support or reject the
hypotheses of the research, as well as qualitative data to
gather broader insight into the public's perception of
mobile augmented reality for urban planning projects.
It could be seen that there was some divide in the results
between the younger and older participants. When
looking at the results of the mobile device familiarity
questions, it could be seen that the younger participants
were generally more familiar with mobile technology
than the older ones; a result that could have been
anticipated. This same divide seemed to appear again
when the participants were asked how easy the system
was to use; the younger subjects responded more
positively than the older group.
The same trend was seen again when inspecting
participants' willingness to participate in urban planning
events. Here, only the responses from the younger
participants (the 18-25 age group) showed an increase in
willingness if they were to have access to the kind of
system introduced in this study. The overall difference in
means between both questions did increase however as
the response from the older group remained the same for
both questions. The overall mean increase was shown to
be significant.
The qualitative feedback gave an impression of how the
public reacted to the prototype system. The feedback was
generally very positive, especially among the younger
19
participants. They saw the prototype system as a useful
tool for visualising proposed architectural designs,
although participants would have liked to have had access
to more information about the designs. Participants
generally showed an understanding of how to view the
augmented-reality rendered designs, suggesting that the
augmented reality approach to visualising 3D architecture
was not too difficult to pick up for new users.
The feedback showed that the participants had a range of
reasons to believe that the project planners would not
consider their participation in the urban planning event,
but thought that if enough people used the system and if
the results were made public, then their contribution
would be of more importance. That the prototype system
was “nice and simple” to use and “easy to understand”
suggests that it may help reduce the rational ignorance
citizens have towards participating in urban planning
projects described by Krek (2005).
Participants in the field study showed an increase in their
willingness to participate in urban planning events with
the use of a smart-phone augmented reality system. The
research could not, however, show the effect such a
system would have on the public’s perceived participation
during planning events. Valuable feedback was obtained
which suggested that smart-phone based systems like the
one introduced in this research would be valuable for
helping the public visualise proposed architectural
changes to the urban environment during planning events.
FUTURE WORK
Considering the positive and thoughtful feedback
gathered from the public during this research, future work
could be done in improving the prototype system used
here. This could include designing ways to incorporate
extra information about the designs and urban planning
events, and allowing users to view higher quality models
from multiple viewing angles. In terms of increasing the
public's perceived participation in urban planning, the
system could be extended to allow for web functionality
in order to make the user's feedback public and to allow
for a sense of community among the participants of the
urban planning event. Further extension could allow users
to upload their own design concepts, or modify existing
ones, to better share and understand their ideas about their
urban environment. This could include a desktop PC
version of the system working in conjunction with the
mobile version, to extend the functionality beyond the
limitations of the smart phone device.
ACKNOWLEDGEMENTS
Thanks to Josh Jeffery and the DESI313 Environmental
Design students for their 3D models, and to Tobias
Langlotz for his support with the software and for
implementing the panorama tracker. To those who
participated in the heuristic evaluation and field trial,
many thanks for finding the time to help out, your
feedback and input was greatly appreciated. Finally,
thanks to Simon Hoermann and Lavell Müller for their
assistance with the project, to Claudia Ott for her help
with the user interface design, and to the reviewers for
their helpful feedback.
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