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Bottleneceks in Adoption of AR written in 2014

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Avestia Publishing
Journal of Multimedia Theory and Application
Volume 2, Issue 1, Year 2014
Journal ISSN: pending
DOI: TBD
Date Received: 2013-12-30
Date Accepted: 2014-03-16 27
Date Published: 2014-03-31
Drivers and Bottlenecks in the Adoption of
Augmented Reality Applications
Héctor Martínez1, Danai Skournetou2, Jenni Hyppölä2, Seppo Laukkanen1 and Antti Heikkilä2
1SenseTrix. PL 20, 00101 Helsinki, Finland
[email protected]; [email protected]
2bgator Ltd. Hermiankatu 6-8H, FI-33720 Tampere, Finland
[email protected]; [email protected]; [email protected]
Abstract- In the last decade, Augmented Reality (AR) has
been one of the emerging technologies that have been in the
centre of attention among academics and business
practitioners. Despite the numerous studies which have
demonstrated the multitude of benefits derived from AR
applications, the technology has not reached yet its full
potential due to various bottlenecks which are preventing it
from becoming the mainstream technology that many have
anticipated. In this paper, we first present briefly the history
of AR followed by the evolution of related software
algorithms and hardware devices. The main contribution of
this paper is the overview of the drivers and challenges
related to the adoption and diffusion of AR across five major
application domains; (a) industry and military, (b) training
and education, (c) travel and tourism, (d) medicine and
health care and (e) retail and marketing. Such overview
facilitates especially a cross-domain comparison, which here
enabled us to identify a list of five drivers and five bottlenecks
in the adoption of the current AR technology.
Keywords: Augmented Reality, drivers, bottlenecks,
technology adoption.
© Copyright 2014 Authors – This is an Open Access article
published under the Creative Commons Attribution
License terms http://creativecommons.org/licenses/by/3.0).
Unrestricted use, distribution, and reproduction in any
medium are permitted, provided the original work is
properly cited.
1. Introduction
Augmented Reality (AR) is a concept where
elements from real life are augmented by additional
visual information after recognizing the environment
in order to guide the augmentation (i.e. to position
and orientate augmented content). In 1994, Milgram
and Kishino defined a Virtuality Continuum (VC) [1].
In this continuum, the concept of Mixed Reality (MR)
is set between two ends: (a) Virtual Reality (VR), an
environment where the user is totally immersed in
and (b) Real Environment (RE). MR refers to the
combination of elements from both ends of the VC (i.e.
a mixture between real and virtual worlds). One state
inside the VC is AR, which refers to those cases where
the RE is augmented by virtual objects. This definition
explains the most common approach of AR nowadays,
where images of a real environment (e.g. video feed
from a camera) are augmented with elements from
virtual worlds in real time (e.g. 3D model, images,
videos, text, etc.).
The first known reference to AR concept was
provided in 1901 in [2] where the idea of overlaying
metadata on top of people (basically, information
about their real character) through the use of
spectacles was mentioned. Yet, it took almost a
century until the AR term was first announced in 1990
by Tom Caudell [3] when he was working for Boeing
and one of the first AR-relevant papers was published
in 1992, presenting an AR system prototype called
KARMA [4]. The same year, one of the first AR systems
(Virtual Fixtures) from US Air Force was released [5].
Even though AR was introduced in early 1990s, the
technology that is based on has its roots deeper
embedded in history. Specifically, AR evolved from VR
which in turn originated from simulators in 1920s.
For instance, in 1950s, Morton Heilig introduced
Sensorama (patented in 1962 [6]), the first machine
with AR elements that provided sensing-related
techniques utilizing 3D images, sound, wind,
vibrations, and aromas; however, it never sold
commercially largely due its high cost, complexity and
scalability limitations. Also, in 1961 the first Head
Mounted Display (HMD) was introduced [7].
AR development became easier after Hirokazu
Kato from HitLAB introduced ARToolKit in 1999 [8].
This among other technological developments
(namely gained by computer gaming industry) in
early 2000 attracted more developers to AR. Due to
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the increasing interest in AR technology, researchers
and experts from different fields are nowadays
working together to develop new applications that
can bring the benefits of AR technology to the
respective fields. The number of different useful
applications and recent developments of smartphones
and AR-goggles by large companies like Google [9],
indicate that AR can be one of the hyped technologies
in the next years.
Despite the numerous studies demonstrating the
multitude of benefits derived from AR applications,
the technology has not reached yet its full potential
due to various bottlenecks which are preventing it
from becoming the mainstream technology that many
have anticipated. While there is a large amount of
studies discussing the benefits and problems
encountered in the adoption and diffusion of AR
technology, the majority of these focus on a single
application field of AR. Motivated by this observation,
in this paper, we study what drives but also what
impedes the adoption of AR technology across five
major domains, and taking into account both the
developers’ and final users’ perspectives. The main
goal is to provide a general overview of the current
state of the art and to provide hints for future
developments.
Unlike the invention of a new technology, which
often appears to occur as a single event or jump, the
diffusion of that technology usually appears as a
continuous and rather slow process. Yet it is diffusion
rather than invention or innovation that ultimately
determines the pace of economic growth and the rate
of change of productivity [10].
Technology acceptance models are used to
explain how users come to use or accept a specific
technology [11]. For instance, Louho et al. defined
technology acceptance as the way people perceive,
accept, and adopt technology use [12]. According to
the Technology Acceptance Model (TAM), the success
of a system is based on an individual’s behavioral
intention (i.e. attitude) to use it and this is determined
by two factors: perceived usefulness and perceived
ease of use [13]. Perceived usefulness is defined as the
degree to which the user believes that using the
system will enhance his or her performance.
Perceived ease of use is defined as the degree to
which the user believes that using the system will be
free from effort.
According to Rogers innovation diffusion theory,
five characteristics of a technology determine its
acceptance [14]:
 Relative advantage (the extent to which it offers
improvements over available tools),
 Compatibility (its consistency with social
practices and norms among its users),
 Complexity (its ease of use or learning),
 Trialability (the opportunity to try an innovation
before committing to use it),
 Observability (the extent to which the
technology’s gains are clear to see).
The remainder of the paper is structured as
follows: section 2 describes the AR-related software
and hardware and how these have evolved over time.
Section 3 overviews the drives and bottlenecks in AR
adoption across five of the fields where AR has been
used most extensively. In section 4, a discussion about
the drivers and bottlenecks is presented. Finally,
section 5 presents the conclusions.
2. AR Software and Hardware
The evolution of AR has been tied to the available
computational power. In particular, during many
years in the past, computers were not powerful
enough to process video feed, analyse it and overlay
virtual content on top of it in real-time and with the
necessary level of accuracy. With the increasing
availability of computational power, the AR-related
techniques have evolved and more complex
algorithms can nowadays be supported. Moreover, the
current trends show that even more advanced and
complex techniques would be supported in the
following years.
There are two main challenges in AR
development related to software: the recognition of
the environment and the rendering of virtual content.
As the rendering of virtual content is a mature
technology thanks to VR, AR researchers have focused
mainly on the former task, i.e. the recognition of the
environment. This has been performed traditionally
using computer vision algorithms or positioningbased systems. Marker based algorithms have been
widely used long in the past as they enable a robust
and fast recognition process. ARToolKit [8] and
derivative studies have diffused the use of markerbased systems and nowadays, these are still one of the
most important approaches. However, this approach
is limited by the requirement of attaching the markers
to the real world and thus, new approaches were
studied in order to overcome the above limitation. For
instance, the evolution of computer processing
enabled the use of image-based algorithms. The main
benefit compared to marker tracking is that no
additional markers need to be placed in the real
world, as images that are already present in the
captured video can be used.
One of the current research trends is to detect not
only real objects but also humans. Specifically, point
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cloud based systems allow detecting real objects using
their corresponding 3D models not only for the
augmentation, but also for the spatial recognition and
also to track movements of humans. As it can be seen,
the evolution of software algorithms towards a more
natural tracking system is a constant. However, it
requires higher computational power and therefore,
the standardized use of these tracking systems is still
far in the time.
From the hardware point of view, there are three
main components required in the majority of the AR
applications. The first component is a camera that is
used to capture the real environment (although the
use of the camera can be avoided in some see-through
systems that may use GPS or non 3D positioning of
virtual elements). Almost any kind of off-the-shelf
camera (e.g. USB cameras, built-in cameras, IP
cameras, industrial cameras…) can be used for an AR
application, depending on the requirements of the
rest of the hardware. The video captured from the
camera (or any other spatial acquired information),
together with the virtual information, needs to be
processed by the second component, i.e. the
computing unit. The last component is a device where
the final augmented information is displayed (e.g. a
flat screen). Additionally to these three elements,
further hardware, e.g. GPS, human motion sensors,
accelerometers, gyroscope, etc., can be included into
the designed system in order to serve a specific
purpose.
Traditional computers with USB or built-in
cameras and flat screens have been the most common
setup for the early AR systems. However, with the
growing computing power of handheld devices (i.e.
smartphones and tablets), AR technology has started
to be integrated also in these devices as they are
constitute all-in-one hardware systems. In 2008-2009,
the first commercial AR browsers for smartphones
were introduced. These AR browsers were based on
GPS tracking instead of computer vision, as the
computing power was still not enough for image
recognition. With the fast evolution of smartphones
and the expansion of tablets, the number of computer
vision based AR applications is growing rapidly.
Moreover, Head Mounted Displays (HMD) have been
for long in the centre of attention among researchers
because they can also serve as all-in-one devices.
However, so far existing prototypes have been heavy
to use and the computing power has also been limited,
preventing their wider adoption.
In the recent years, new lighter glass-type devices
have started to appear with higher computing power
which makes them particularly suitable as AR devices
(e.g. Vuzix Wrap 1200DXAR [15], Google Glass [9]).
The last Consumer Electronics Show (CES) has shown
this trend as several AR-glasses have been presented
(e.g. Epson Moverio BT-200 AR glasses [16], Lumus
DK40 smartglasses [17], ORA-S AR eyewear [18], etc.).
In the future, it is expected that these devices will
further evolve enabling an even higher number of AR
applications for these devices to be developed. Finally,
cloud services are nowadays a new trend in the AR
field which may lead to a new standard of AR
computing. Moreover, the use of cloud services is very
tempting because it enables the utilization of
powerful computer vision algorithms with low
requirements of hardware, as the majority of the
calculations are done remotely. Therefore, if the
tracking is done in the cloud, a smoother rendering
can be achieved with the same hardware. However,
cloud technology also presents some drawbacks, such
as the need of continuous connection to internet for
the cloud processing and an appropriated bandwidth
for the targeted cloud service.
3. AR Applications – Drivers and Challenges
3.1. Industry and Military
Industry is one of the fields that may take more
advantage of AR technology than other fields, as it can
be applied to the whole life cycle pipeline, starting
from the design of the product and going through the
workers’ training, the product manufacturing and the
maintenance of the facilities. Figure 1 shows a block
diagram of the current possibilities of AR in the
product pipeline. These possibilities are explained in
this section, except the marketing of the product that
will be explained later in a separated section.
Figure 1. Product pipeline and the uses of AR.
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Product design is usually an expensive process
for the majority of companies, as either a physical
prototype (in fact, several iterations of prototypes) or
a Virtual Reality model displayed in a Cave Automatic
Virtual Environment (CAVE) like system is needed.
The use of AR technology allows designers to create
real scale virtual prototypes that would be very
expensive to build (e.g. cars, heavy machines, etc.) and
analyse and present them augmented in a real
scenario with a low cost solution. Thus, AR can be
used at an early stage prototype design phase to
reduce costs and provide means of design interaction
either in a real size or in a desk size environment [19].
Designers may get interested in AR not only for saving
costs, but also for some additional features like
tangible interaction [20], [21], the easiness of
visualizing changing variables like size, colour or
textures [21] or the possibilities of usability
evaluation [22].
Although the use of AR for training purposes is
discussed later in this paper, it is worth to mention
that AR may bring standardization of the
manufacturing training which in the end would
reduce costs and training time and allow workers to
learn at their own pace [23]. During the training
phase, the real devices can be augmented to guide the
trainee through the different steps to follow, highlight
some specific parts of the devices or point out
dangerous parts and/or procedures that need to be
avoided, for citing some examples. Several studies
have already shown positive results when using AR
for guiding the assembly process (e.g. [24], [25], [26]).
The results from [27] show that the use of AR for
assembly provides faster and more accurate
performance for psychomotor phase activities.
Although these studies have been carried out for small
size prototypes, benefits like higher accuracy with
fewer errors and shorter assembly times depict a
promising future for larger scale projects. For
example, [28] presents a first phase to create a large
scale AR assembly process in the aerospace industry.
Moreover, AR can be also used for final inspection of
the manufactured products [29].
Maintenance is probably the most active research
field in AR for industry and there is a large number of
studies that have described the benefits of using AR
for maintenance (e.g. [30], [31], [32]). Some of the
benefits are faster maintenance interventions with
fewer errors and more efficient and safer procedures.
Furthermore, remote guidance and supervision from
an expert is also possible by means of AR [33]. Several
AR prototypes have been already implemented for
maintenance in different sectors, such as aerospace
industry [31], remote handling [34], photovoltaic
pumping systems [35] or acid treatment industry [36]
for citing some recent examples.
The great majority of research studies are
prototypes aimed to solve a specific problem.
However, the use of AR in industrial environments
requires flexibility [37]. This flexibility means that the
AR tools should be easily reusable to adapt to
different devices and procedures with little effort. The
solution to this issue could be the standardization of
the patterns to be recognized by the system, like the
unique identifiers proposed in [38], and the
implementation of authoring tools that allow facilities
to create their own AR applications without the need
of dealing with low-level AR programming.
Military field has also started to research actively
the use of AR technology not only for training (e.g.
[39]) and maintenance (e.g. [40]) but also for
simulation of actual military operations, like the
prototypes presented in [41] and [42].
One of the main drawbacks of utilizing AR in
industry and military fields is the accuracy of the
virtual elements positioning. For instance, when using
AR for the product design, the accurate placing of the
prototype models is difficult to achieve [19].
Sometimes the low accuracy comes from the tracking
algorithm itself which sometimes relies on
environmental variables such as light conditions.
Another important drawback of AR is that the
recognition and tracking can be time consuming
processes which complicate the direct use of the inplace objects for tracking in real time. Although some
studies have shown good results in this direction (e.g.
[31], [34]), a standardized method for markerlessbased AR systems for large facilities is still far from
the status of current technologies. Due to this fact, it is
common to use marker-based AR systems which can
provide a robust real time performance for large
projects. However, this approach is not always
convenient as the placing of markers in the facilities
may not be possible or desired [31].
Despite the advantages mentioned through this
section, it is still not clear for the industry whether the
use of AR technology would return the investments
made in the implementation of the system [23], which
may be the major impediment in the generalization of
AR applications in industry environments.
3.2. Training and Education
According to [43], AR is one of the ten most
important emerging technologies for humanity,
especially when it is used in educational
environments. The reasons of this asseveration
usually rely on the inherent characteristic features of
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the technology, i.e. immersive environments and
interactivity.
The combination of real environments with
virtual objects creates an immersive feeling for the
user. As stated in [44], immersion in a digital
environment enhances education in terms of multiple
perspectives (i.e. changing frame of reference),
situated learning (i.e. learning in the same context
where the knowledge is applied) and transfer (i.e. the
application of the acquired knowledge). AR is also a
highly interactive technology which makes it suitable
for the concept of “learning by doing” [45]. The
interaction possibilities range from the basic
interaction with virtual objects (e.g. moving 3D
models, playing videos, scaling objects, etc.) to
complex interactive features, like an embedded
intelligent virtual tutor [46] or interaction between
physical and virtual objects (i.e. tangible interfaces)
[47], [48].
Moreover, AR brings further features to
education and training. Collaborative applications
have shown to be of great interest in this field and
several studies have already shown the benefits of
creating collaborative AR environments (e.g. [49],
[50], [51]). AR is not only a means to educate and
train people, but also to entertain while acquiring new
knowledge. Students usually find concept acquisition
more interesting when using this kind of systems [52].
Last but not least, AR technology has a fast learning
curve, which means that users are able to start
utilizing the applications with very little prior
information [53], [54].
AR can be used in almost any educational subject,
as it has been demonstrated in the large variety of
examples that can be found in the literature, such as
mathematics [55], [56], physics [57], [58], chemistry
[47], [50], languages [59], medicine [60], Earth and
environment learning [51], [61], natural sciences [54]
or music [62], [62]. The applications can be targeted
to a wide range of ages, from preschool students [54]
to University students [49]. AR can be also used for
training professional workers in several fields, such as
training on clinical breast exam [64], planning brain
surgery [65], [66], bread production in a bakery [46],
full-body movement [67], myoelectric prosthesis [68]
or escape guidelines for nuclear accidents [69].
There is no common standard on how to deploy
AR applications for education and training. However,
there are some common approaches that are followed
by a large number of studies. One of the most common
approaches is to use AR to augment the content of
books where traditional educational or training
material is explained in the form of text and images.
The content used for the augmentation may cover a
wide range of multimedia elements (3D models,
animations, videos, webpages, etc.) and also several
means of interaction that provide an added value to
the books. Starting from one of the first AR books, the
widely known MagicBook [70], where users could
immerse themselves in a virtual world, researchers
have been augmenting books for different subjects
with all kind of educational material to enhance the
learning process (e.g. [71], [72], [73]). The inherent
interactivity of AR technology leads to a common and
widely used approach where hand-sized markers are
handled by students in order to analyse complex 3D
representations that are not easy to understand when
seen as printed images or to interact with the learning
content in educational games. Another common
approach is to introduce virtual characters in the AR
scene to act as teachers, tutors or training guiding
characters (e.g. [46], [74], [75]).
As it can be seen from the previous
considerations, there is no unified procedure for the
development of AR applications, as the variability of
needs is large in the educational and training fields.
Moreover, there is a gap between application
developers, mainly from programming and IT fields,
and educators and trainers who provide the
educational value. Several approaches have tried to
fill this gap by providing authoring tools to educators
and trainers (e.g. [76], [77], [78]). Another approach is
the one proposed in STEDUS [79] where a common
platform provides access to educational AR
applications that have been developed by
programmers from the specifications designed by
educators.
Despite the large number of research studies in
this field, the level of acceptance is still limited. Some
reasons may be that as an emerging technology,
people are not used to utilize the technology or they
even do not know what AR is. This applies not only to
educators, but also to students who, as reported in
[80], may feel overwhelmed with the large amount of
information and the complexity of the educational
tasks. In that paper, the authors also point out that
some educators are unwilling to let the students
experiment with the AR applications by themselves
fearing that they may get lost in the process. Another
problem may be, as stated before, that the majority of
the applications are developed by programmers
without the appropriate pedagogical point of view
which may lead educators to ignore the potential
capabilities of the technology.
3.3. Travel and Tourism
The travel and tourism industry is one of the
fastest gowning industries across the world. For
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instance in Europe, it comprises 1.8 million
enterprises, many of these being SMEs, and
contributes to more than 5% of European GDP [81].
Tourism includes the activities of persons travelling to
places outside their usual environment for recreation,
leisure, business and other purposes. The tourism
market relies heavily on information and technology
plays an increasingly pivotal role not only in the
delivery of it but also in the overall enhancement of
tourists’ and travellers’ experience.
Among the various technologies employed in this
heterogeneous industry (which includes tourist
attractions, accommodation, bars and restaurants,
transports, tourist offices, etc.), AR can be used across
the value chain. In particular, AR can be used to access
information about physical objects “on-the-go” via
mobile AR browsers which deliver information
through spatially registered virtual annotations and
can function as an interface to (geo)spatial and
attribute data [82]. For example, one can browse the
history of Greece, see the Berlin Wall and other
historic sites as well as see information about nearby
business, e.g. the today’s menu of the restaurants
nearby. AR browsers have achieved more than 20
million downloads from mobile app stores [83] and
some of the most common examples are Wikitude
(launched in 2008) [84], Layar (launched in 2009 by
SPRXmobile) [85] and Junaio (launched in 2009 by
Metaio) [86]. Other, less popular, AR browsers are
Sekai Camera (launched in 2009 by Tonchidot) [87],
Tagwhat (launched in 2010) [88] and Argon
(launched in 2011 by Georgia Tech) [89].
Exploring new places is the most common
motivation in tourism and therefore navigation is very
important. AR technology can also be used to facilitate
access for visitors to and within a destination by
overlaying virtual arrows on the live view in real time
that indicate the direction the user should follow.
Currently, there are many mobile applications
available that utilize AR; few focus exclusively on
pedestrians (e.g. [90]) or drivers (e.g. [91]), while a
larger number focus on several modes of commuting
or travelling (e.g. [92], [93], [94]). Moreover, the
automotive industry is also interested in in-car AR as
a means of enhancing drivers’ safety. For instance,
Mercedes-Benz is developing an In-Vehicle
Infotainment System based on AR for its in-car
navigation system which would have a split-view
display in order to minimize distraction for the driver.
Apart from navigation, the translation of information
(e.g. menus and signs) is also very important in the
tourist sector and AR can be utilized to instantly
translate foreign text by pointing the mobile device’s
camera at the text (e.g. [95], [96], [97]).
AR can be used in cultural institutions for engaging
visitors and enhancing their experience through
interactivity. For example, the Digital Binocular
Station (DBS) used in Canterbury Museum is based on
a traditional binocular station, but adds a layer of
interactive, 3D stereoscopic digital content between
the user and their view [98]. Stedelijk Museum in
Amsterdam used AR to install artworks in a local park
[99], the Royal Ontario Museum used AR to add flesh
to the bones of dinosaurs [100] while the Asian Art
Museum recently unveiled a new AR application for
its Terracotta Warriors exhibit [101]. AR applications
have been also developed for further promoting
tourism in particular regions. For instance, Tuscany+
[102] and DiscoverHongKong-City Walks [103]
applications offer visitors in Tuscany and Hong Kong,
respectively, an interactive, real-time AR-based guide
for experiencing city’s vibrant living culture while AR
city tours are offered in Seville [104]. There are also
mobile tourist guides which utilize AR but are not
limited to a single region such as GuidePal [105],
mTrip [106], and GeoTravel [107].
Despite the increasing use of AR in tourist-related
mobile applications, there are several obstacles
reported in the literature which prevent the wider
adoption of this technology. One such problem is the
lack of interoperability across mobile platforms which
affects both application developers and content
aggregators [108]. Moreover, many apps often require
Internet connection which can limit greatly their use
considering the high cost of data roaming [109]
(although the effect of this is likely to decrease in EU
when data roaming charges may get unified across
Europe). Other major factors hindering the adoption
of AR applications for tourism are the scarcity of
available content, the poor quality of the user
interface and user experience, as well as issues with
battery life likely caused by the variety of sensors
involved [110]. For example, many of the existing
marker-less smartphone AR applications do not
support extensively value-adding functionalities for
mobile tourism such as Context-aware push of
information, m-Commerce, Feedback and Routing
[111]. In addition to technical limitations, aspects
such as information abuse or oversaturation for
marketing reasons and data privacy could also affect
negatively the adoption of these in applications in the
tourism sector [112].
In order to facilitate the adoption of AR in
tourism, a number of critical design issues have to be
addressed. For instance, according to [109], the
criteria that need to be taken into account when
developing an AR application specifically for tourism
are (a) efficacy (e.g. does the system work as it was
33
planned for and does it provide the required
information to the right users?), (b) efficiency (e.g. are
the AR application functions fully exploitable?), and
(c) effectiveness (e.g. does the new AR system provide
better tourist support?). AR app developers focusing
on tourism also need to take into account future
trends in this sector such the shift of demand from
mass tourism to more tailor-made customized
tourism for individual travellers [113]. All in all,
innovative AR solutions can become the key to the
promotion of tourism or tourist regional development
therefore. However, it also important for relevant
stakeholders to come along on this move toward
innovative strategies, knowing that it will cost money,
require a lot of training, and take time [114].
3.4. Medicine and Healthcare
Medicine is one of the most important industries
for human well-being and health. The technological
development has enhanced the quality and
possibilities of medicine. Many illnesses and abnormal
conditions that earlier caused constant pain or death,
such as cardiovascular diseases or many cancers, can
now be cured by modern technologies,
pharmaceuticals and surgery.
The possibility of using AR and VR in medicine
was recognized already in the late 1990s [115].
Benefits of using AR in medicine include a possibility
to increase the (virtual) transparency of the patient,
higher accuracy and precision with fewer risks,
possibility of diagnosing the patient’s condition
during surgery and guided surgery within less time
[116]. AR is especially useful in surgery. Together
with 3D visualization and modeling, AR can be used to
provide a virtual transparency of a patient and thus,
help surgeons to conduct minimally invasive surgery
that provide greater benefits to patients [117]. AR
supports Minimum Invasive Surgery (MIS) approach,
aiming at the least possible inconvenience for the
patient. AR may also prevent patient and operator
from other risks such as exposure to radiation in
some procedures [118]. In orthopedics, VR training
applications for shoulder and knee operations have
been used with good results [119], [120], [121].
Augmented reality has proven to be useful in
after-stroke re-education (e.g. [122], [123], [124],
[125], [126]). Luo et al. [125], [126] got promising
results by creating an AR training environment for
rehabilitation of hand opening in stroke survivors.
They used mechanical devices to assist finger
extension. However, the patient required a therapist
to assist wearing the equipment. A musical AR game
has been created to develop patients’ motor
coordination, providing a natural fingertip/toe
tipbased interaction [127], [128]. An AR-based
rehabilitation system for daily practice, using a 2-D
web camera and fiducial markers was proposed by
Alamri et al. [129]. A table-top home-based system
proposed by Mousavi Hondori et al. [123]
rehabilitates wrist, elbow and shoulder by tracking
the patient’s hand and creating a virtual audio-visual
interface for performing rehabilitation-related tasks
that involve wrist, elbow, and shoulder movements.
The system can be used by the patient and a therapist
may follow and modify the exercise as the system
sends the real-time photos and data to the clinic for
further assessment.
Presurgical cranial implant design technique that
develops custom fit cranial implants prior to surgery
using the patient’s computed tomography (CT) data
was pioneered in 1996 [130]. In 2004, it was shown
that virtual 3D cranial models based on patient CT
data can be created in a haptic AR environment, thus,
using force feedback to simulate a sense of touch,
which is essential while creating realistic and reliable
models [131].
Despite the numerous benefits of AR in the
medical field, some issues have arisen, including, for
example, incorrect visualization of interposition
between real and virtual objects [132], [133]. A
challenge in surgery is that the position of organs and
tissues cannot be estimated but the surgeon must
know them exactly. AR projections do not always
correspond the reality because of the structure of
tissues in human body and patient’s subtle
movements, such as aspiration and other tissue
function [115], [134]. An attempt to provide more
realistic real-time data was made by Konishia and al.
by integrating laparoscopy and 3D-ultrasound images,
i.e. combining images inside and outside a body,
provided by two different imaging methods [134].
As described earlier, AR is beneficial also in
training doctors, as well as in medical education and
while explaining patients their condition and
treatments. AR provides a realistic method to train
medical skills, as well as objective feedback, without a
presence of an expert supervising the exercise [136].
AR aids medical trainees to acquire proficiency in
required procedures [137]. The enhanced reality
compared to traditional learning methods enhances
memorability of the procedures and thus, the
efficiency of training and the speed of learning [138],
[139].
3.5. Retail and Marketing
The retail industry involves the sale of products
and merchandise online or from a static location, such
as a physical store. It is also coupled with marketing
34
activities undertaken by a retailer with the purpose of
promoting awareness of the company’s products and
increasing sales. While e-commerce has improved
dramatically over the last 20 years since Amazon was
founded, still a large percent of all retail commerce is
being done in the brick-and-mortar world. As an
attempt to bridge this gap, many retailers, small and
large, have increased their investment in their ecommerce divisions but one of the biggest challenges
they face when entering the online shopping space is
the lack of interaction with physical products.
Moreover, retailers have traditionally relied on print
advertising campaigns or other media to promote
products. With the increasing use of tablets and
smartphones, the use of augmented reality technology
could completely transform the way traditional retail
and marketing activities are done [140].
In the retail industry, AR can bring major benefits
both in the online and brick-and-mortar sectors by
enabling the interaction with virtual objects and
enhancing the shopping experience with capabilities
offered by the Internet, respectively. Specifically,
there are many advantages in using AR in the retail
industry [141]: It can improve the conversion rates
and reduces returns for clothing stores via the use of
virtual fitting rooms. Such rooms allow customers to
sample products online as clothes are automatically
overlaid on the consumer`s real-time video image
through their webcam. For example, both
Bloomingdale and J.C. Penney have tested the use of
virtual dressing rooms, which let customers “try on”
outfits that appear when they are looking at
themselves on a large screen. In addition, the clothing
retailer, American Apparel, is also adopting AR
technology with the aim of bringing the online
experience offline. By using a particular application,
in-store patrons can scan the item to see the product
in different colours and read reviews by other
customers who have bought that item [142].
Besides clothing, AR allows customers to try a
product before they buy it with the use of a 3D
preview, as in the case of Lego. Major beauty retailers
also plan to offering customer a new way to try out
new makeup with the help of 3D AR Makeup and AntiAging Mirror which was unveiled at the 2014 CES
conference by ModiFace. Moreover, the assembly of
models can be digitally displayed on products, such as
furniture, that require at-home assembling. This
increases convenience and perceived flexibility to the
online shopping experience. For instance, IKEA has
utilized AR for visualizing the 2014 product catalogue
and providing a virtual preview of furniture in a room.
In 2014, Matterport, along with a growing and diverse
list of companies, will start selling software to the
public that can create a 3-D rendering of indoor
spaces such as the inside of a house. People can view
the rendering on a computer screen, explore the
house as though taking a video tour and add objects to
rooms. Such application could be also be utilized in
construction, home improvement and insurance
industries. Furthermore, AR can be used to optimize
the warehouse space resulting in the reduction of
time needed to process orders. For instance, Vuzix
and SAP have created a partnership with the aim of
developing AR applications for data collection and
warehousing.
With the help of AR technology, additional
information can be displayed about products in order
to enrich the shopping experience, enable customers
to search for nearby deals and attract them inside a
store. Yihaodian, China’s largest food e-commerce
retailer launched in 2012 a chain of 1000 “virtual
stores” with an AR mobile app that allows customers
to shop in public places across the country. Glashion, a
fashion app recently released for Google Glass allows
users to purchase fashion items online as soon as they
spot someone else wearing it. Pocket BargainFinder, a
handheld device for augmented commerce allows
customers to physically inspect products while
simultaneously perform a price comparison online
[143]. Another AR application, called TrackMyMacca,
was lunched in Australia with which customers of
McDonald’s could see what their meal is made of
[144].
AR technology can also be regarded as an
effective marketing to enable a new form of
visualization and interaction. In particular, AR can
enhance brand recognition and empowers advertising
campaigns. For example, Accenture has developed an
app for Google Glass that allows customers to explore
Toyota showrooms and check out new cars. Another
example is Unilever, a global hygiene and personal
care brand, launched in Buenos Aires an interactive
AR campaign to promote one of their products [145].
AR, which has been used in marketing campaigns, can
be seen as a form of experiential marketing because it
focuses not only on a product/service, but also on an
entire experience created for the customers [146],
[147].
While the use of AR in retail and marketing is
increasing, there are still several obstacles preventing
its mass adoption. Specifically, only a fraction of
consumers with Internet access have a webcam and
the majority of mobile handsets are unable to support
AR activities or have a limited computational power.
Also, awareness is low and not every product is
outfitted with the ability to display the interactions
[148]. Therefore, relevancy of idea with the product
35
should be taken into consideration when designing
AR applications for the retail and marketing sectors.
4. Analysis of Drivers and Bottlenecks
AR has been an active research topic during the
last decade and its importance will likely increase in
the future as technological advancements (e.g. new
hardware devices, more computational power, etc.)
could fuel further the development of AR technology
as well as help overcome existing bottlenecks. Several
benefits and bottlenecks regarding the use of AR in
five different domains have been discussed in this
paper. Such approach enables us not only to identify
the domain-specific benefits/bottlenecks but also to
expose potential commonalities. One of the most
commonly encountered benefits of AR across the
examined domains is the reduction of various types of
costs. For instance, as a tool for learning and guiding
(e.g. in maintenance tasks, in medical procedures,
etc.), AR helps to learn faster and reduce errors which
leads to increased time savings, safer procedures and
less operational costs. Furthermore, AR can also
reduce fixed costs such as those related to the
purchase of various items as virtual objects can
replace physical ones (e.g. using virtual robots instead
of real ones for the path planning phase). Moreover,
the use of virtual objects is also beneficial in terms of
reduced damage costs (i.e. virtual items cannot be
damaged by misuse) as well as development costs
(e.g. in product development, the use of virtual
prototypes can be employed in the design phase to
fine-tune the development of the final physical
prototype).
AR is still an unknown technology for many
people. Although this is still a problem for the
expansion of the technology, its fast learning curve
and the curiosity make it already suitable for many
contexts, like education, training, or leisure activities
(e.g. tourism). Moreover, the use of AR also allows
users to visualize content that cannot be easily viewed
otherwise. For example, it is possible to see the 3D
disposition of the planets in a desk-size environment,
recreate in-place 3D environments of historical
moments, view the interior of the human body or
understand 3D objects that are usually printed as
images in books. Although the visualization of 3D
content has been done for several years in VR field,
the possibilities of tangible interaction and in-place
visualization (mixing reality and virtuality) that AR
provides, together with the fun side of its use, make
AR a solid alternative that can overcome traditional
VR applications in several fields. However, as it has
been explained in this paper, there are also some
common problems that still prevent AR from being a
mainstream technology.
Nowadays, there is no standard for the use of AR
technology. Although the creation of an all-purpose
standard would be a very challenging task, defining
several standards for different purposes would be a
more realistic approach to follow. For example, the
standardization of AR use in the tourism field has
already shown some progress when considering the
related AR browsers. However, the content of these
browsers is still not common as it could be, for
instance, in traditional web browsers. For this reason,
the majority of existing applications are still of
prototype level with the lack of flexibility being often
a common denominator. Nonetheless, several tools
have been already developed to help overcome the
flexibility problem, but the efforts need to be still
increased.
From the technological point of view, there are
two main problems nowadays which hinder the
adoption and diffusion of AR; these are the lack of
accuracy (e.g. light conditions affect to the right
alignment of virtual objects) and the time consuming
algorithms (which may be an important bottleneck in
some devices with limited computational power).
While both of these problems have been tackled
during the last years and some progress has been
made towards achieving higher alignment accuracy
and reducing the algorithms’ complexity, the demand
for more robust AR applications is yet to be met.
In the recent months, a new bottleneck has arisen
as a major issue: the compatibility with social
practices. As we have described before, there is a
current trend on new devices in form of glasses or
HMDs. Although the majority of these devices are
used in specific environments (e.g. training rooms,
maintenance facilities, etc.), some of these devices are
beginning to appear as common accessories in
everyday life (e.g. Google Glass). The possibilities of
these devices in their daily use are unlimited and their
use could boost the development of AR technology.
However, the use of these devices is still far from
being socially accepted. Apart from the inherent
problem of getting distracted by the virtual content
displayed on the glasses while establishing social
relationships, one crucial problem is the privacy
issues that may appear, as stated in [149]. In that
paper, they explain that a new technology may create
privacy concerns at the beginning but this may change
when we get familiar with the devices and with the
real value of using them. Despite this fact, the problem
of social practices may become so important in the
early stages of the product commercialization that
even Google has release a list of “do’s and don’ts”
36
[150] targeted to the users that are currently testing
the device.
Last but not least, there is a risk to overwhelm
users by a large amount of information. Therefore, it
is crucial, to carefully analyse the information before
presenting it to the users (e.g. shops in an AR city
application or instructions for maintenance) in order
to ensure that the amount of information conveyed is
sufficient for the application’s purpose, but not too
much or more than needed as it may distract the user
and limit the outcome of the application use.
If we analyse the drivers and bottlenecks
presented here with Rogers’ innovation diffusion
theory (mentioned in the introduction), we can
conclude that three out of the five characteristics are
already fulfilled by AR, as it is shown in
Table 1. AR shows advantages over VR and other
multimedia technologies, it implies low complexity in
its usage and it is relatively easy to try nowadays
(although not all devices are prepared for AR
technology). However, there are still two aspects that
are not met yet. Although technically AR can be used
nowadays, there are still some compatibility issues in
terms of social practices for some devices (e.g. AR
glasses). On the other hand, the observability of the
benefits of the technology is not clear for all potential
users.
Table 1. Roger’s theory applied to AR.
Roger’s theory applied to AR
Relative advantage (the extent
to which it offers improvements
over available tools).
Compared to VR, AR offers new advantages (e.g. Visualization of virtual worlds mixed
with real environments)
Compatibility (its consistency
with social practices and norms
among its users).
Some devices are not socially accepted yet due to privacy issues.
Complexity (its ease of use or
learning).
AR is easy to learn and to use.
Trialability (the opportunity to
try an innovation before
committing to use it).
AR is easy to try nowadays as many applications are freely available (especially for
smartphones, tablets and consoles). However many users do not have the required
devices to test the applications.
Observability (the extent to
which the technology’s gains are
clear to see).
The benefits are not clearly seen from the consumers’ point of view. Some users are
not aware of the benefits of the technology while others need more information to
know if AR would return the investments made in the implementation of the system
(e.g. investment in AR maintenance systems, investment in marketing and retail
solutions, etc.).
In today’s economy, network effects due to
technology standards are very important because
there is a high degree of interrelation among
technologies [10]. A technology has a network effect
when the value of the technology to a user increases
with the number of total users in the network.
Network effects in adoption can arise from two
different but related reasons, often characterized as
direct and indirect. Direct network effects are present
when a user’s utility from using a technology directly
increases with the total size of the network.
Specifically, in AR direct network effects are relevant
when considering e.g. the user-generated content in
AR browsers where the higher the amount of content
is available, the more probable it is to attract new
users or in the case proposed in [79], where a larger
number of users implies a larger number of available
applications. Indirect network effects also arise from
increased utility due to larger network size, but in this
case the increase in utility comes from the wider
availability of a complementary good [10] such as
smartphones, tablets, head mounted displays and AR
glasses.
5. Conclusions
As a conclusion, this paper has presented an
overview of AR and related technologies and has
introduced the benefits and most common problems
of its use in different fields. Table 2 presents a
summary of the drivers and bottlenecks analysed in
this paper.
37
Table 2. Summary of drivers and bottlenecks in the adoption of AR.
Drivers Bottlenecks
Reduction of
costs
Costs can be reduced by using
AR in several manners (e.g.
reducing costs in manufacturing
processes, reducing errors, safer
procedures, etc.)
No standard and little
flexibility
There is no current standard for AR
applications. The majority of applications
do not allow their use in other domains and
thus, the creation of new applications is
usually required with the additional effort
and time that it entails.
Fast learning
curve
The technology is intuitive and
easy to use. Therefore, the
adoption from newcomers is
easier than in other
technologies.
Limited
computational power
Many AR applications require complex
computer vision algorithms to work. These
algorithms tend to be time consuming for
current devices (especially for mobile
devices).
Curiosity
The idea of “expanding” the real
environment with virtual
content usually catches the
attention of users that feel
tempted to use the applications.
Inaccuracy
Some of the techniques are still not accurate
enough to provide a robust localization of
the virtual content to be displayed in the
augmented view.
Tangible 3D
visualization
Visualization of 3D content in
real life and the possibilities of
interaction offer an added value.
Social acceptance
New devices (especially glasses) are in their
first years of existence and they have not
been fully accepted in social practices.
Fun
The technology offers a
component of fun in many cases
that can be useful in several
fields (especially in education
and tourism).
Amount of
information
The amount of information to be displayed
in the augmented view may exceed the
needs of the user. This problem may
become critical when advertising becomes
popular in AR applications.
From the aforementioned considerations, it can
be concluded that AR technology is not mature
enough to be mainstream (at least not as mature as
VR is nowadays), but the steps followed by developers
are pointing in the right direction. Also, changes in the
perception of the technology from the users in terms
of social practices and the perception of the benefits
from its usage are needed to enhance the acceptation
of the technology. Finally, an increase of the number
of users and devices may create a network effect that
can boost the implantation of AR as an everyday life
technology.
Acknowledgements
This work was carried out in project “Preventing
hUman intervention for incrREased SAfety in
inFrastructures Emitting ionizing radiation
(PURESAFE)” funded by the 7th Framework Program
of the European Union under the Marie Curie Actions –
Initial Training Networks (ITNs).
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