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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Visualizing the Positive and Negative Affordances in the Home Environment During the First Year of Life Using Augmented Reality</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Miho Nishizaki (mnishiza@tmu.ac.jp)</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of System Design</institution>
          ,
          <addr-line>6-6 Asahigaoka Hino-City, Tokyo</addr-line>
          <country country="JP">JAPAN</country>
        </aff>
      </contrib-group>
      <fpage>582</fpage>
      <lpage>586</lpage>
      <abstract>
        <p>This study sheds light on J. J. Gibson's theory of “affordances” by presenting a competent visualization of how infants perceive and act in their everyday home environments, with the aim of preventing accidents and promoting development. Gibson described affordance as a unification of an environment's action-relevant properties and an animal's way of life. To visualize infants' affordances in their natural settings, this study adopted Augmented Reality (AR) technology, which enhances a user's perceptions of and interactions with his/her real environment. In this study, we developed an AR application for iPads and iPhones. We conducted longitudinal observations of two infants from 4 to 12 months of age at their homes in Tokyo, Japan. The findings of these observations revealed 10 typical objects that appeared most frequently among the everyday items found in people's homes. Those objects were assigned to vision-based markers in order of the actor's age and were incorporated into the application. This AR application prototype system was implemented in two ways: (a) Objective-C and OpenCV and (b) openFrameworks and Vuforia. Our informal user study showed that (a) was more suitable regarding recognition time. However, (b) was much broader in terms of the interface design.</p>
      </abstract>
      <kwd-group>
        <kwd>affordance</kwd>
        <kwd>visualization</kwd>
        <kwd>infants</kwd>
        <kwd>everyday environment</kwd>
        <kwd>augmented reality</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction</title>
      <p>Affordance is a fact in the environment as well as a fact
embodied by the act. The ecological psychologist James
Gibson proposed the theory of affordance referring to the
mutuality of animal and environment. The most familiar
living environment is a "home," which includes various
affordances. The process of perceiving affordances is not
the same for all people sharing the same space and objects
as others’ bodily features differ from ours. Still more, an
infant differs from an adult.</p>
      <p>
        Most studies have examined the affordances for infants
outside of their homes, either outdoors or in a laboratory
setting
        <xref ref-type="bibr" rid="ref11 ref14 ref15 ref2 ref3 ref6">(Adolph, 2008; Adolph &amp; Eppler, 1998; Broberg,
2013; Gibson, 2000; Heft, 1988, 1997; Kyttä, 2002, 2004)</xref>
        .
Even though many different approaches have been proposed,
concrete problem analysis and corrective strategies for use
in everyday environments have not been fully clarified.
Furthermore, according to
        <xref ref-type="bibr" rid="ref13">Gibson (1979)</xref>
        , environmental
affordances are what it offers the animal, what it provides or
furnishes, either for good or ill. To correct this, the current
study proposes a novel approach to preventing accidents and
promoting infant development based on the theory of
affordances, which unites our understanding of action,
awareness, and knowledge between the self and the
environment.
      </p>
      <p>
        Empirical research concerning individual affordance has
been advanced based on a series of pioneering studies by
        <xref ref-type="bibr" rid="ref1">Adolph (1995)</xref>
        ,
        <xref ref-type="bibr" rid="ref10">Gibson and Walk (1960)</xref>
        , Stofferegen
(2000),
        <xref ref-type="bibr" rid="ref21">Turvey (1992)</xref>
        ,
        <xref ref-type="bibr" rid="ref22">Warren (1984)</xref>
        , etc. However,
generalization methods have not been thoroughly
established
        <xref ref-type="bibr" rid="ref18 ref19 ref24 ref8 ref9">(Gaver, 1993a, 1993b; Mark, 1995; Mark et al.,
1997; Warren &amp; Whang, 1987)</xref>
        . In particular, little is known
about natural settings, such as the “home.”
      </p>
      <p>
        In this study, we explored the suitable method for an
everyday home environment in order to better visualize
infants’ developmental resources. Technology that enables
the visualization of our environments has remarkable
current real-world applications. First developed over 40
years ago, Augmented Reality (AR) is one such technology
that enables the seamless merging of virtual content with the
real world
        <xref ref-type="bibr" rid="ref4">(Azuma, Billinghurst, &amp; Klinker, 2011)</xref>
        . AR
enhances a user’s perceptions of and interactions with the
real world
        <xref ref-type="bibr" rid="ref5 ref7">(Azuma, 1997; Carmigniani &amp; Furht, 2011)</xref>
        .
Furthermore, developing this technology to work with
mobile devices is one of the biggest and fastest growing
relevant AR research areas
        <xref ref-type="bibr" rid="ref23 ref4">(Azuma, Billinghurst, &amp; Klinker,
2011; Wagner &amp; Schmalstieg, 2009)</xref>
        . While mobile AR has
become commonplace, there is a need for more research
into how to adapt this technology to our fundamental
experiences.
      </p>
      <p>Therefore, the purpose of this study was twofold: 1) to
present an analysis of the affordances of infants’ home
environments based on longitudinal observations during the
first year of life and 2) to propose a new way of visualizing
infants’ affordances by creating an AR mobile application
prototype for iPhones and iPads to provide parents and
surrounding adults with better understanding.</p>
    </sec>
    <sec id="sec-2">
      <title>Methods</title>
      <sec id="sec-2-1">
        <title>Observation</title>
        <p>The longitudinal observations were conducted with two
healthy male Japanese babies, who were observed in their
homes during the first 18 months of their lives. Each family
used a digital video camera to record their baby’s actions at
their home on a weekly basis. This application focused on
data collected between 4 to 12 months of age (the total
recorded time was 75 h).</p>
      </sec>
      <sec id="sec-2-2">
        <title>Design and Development</title>
        <p>(1) Paper prototypes. (2) Designing the app using Adobe
Illustrator CS6, Photoshop CS6, and Shade. (3) Designing
the marker recognition using OpenCV and Vuforia. (4)
Writing an iOS application using Objective-C. GUI and user
interactions were developed using Objective-C.</p>
        <p>Augmented Reality Movies (1) All Augmented Reality
movies were based on the longitudinal observations of two
babies. (2) Hand line drawings that were created based on
the recordings were converted to digital data using
Photoshop and Lightroom. They were saved as 448 px ×
336 px images. The sequences were animated in Photoshop
using the Animation Timeline and were exported as
QuickTime Movies. Figure 1 shows the example of an
infant interacting with a cabinet at age 11 months, 17 days.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Results</title>
      <p>This study proposed an AR application prototype for
iPhones and iPads capable of visualizing the affordances of
infants’ indoor environments during the first year of life. On
the basis of these observations, we extracted objects.
According to Gibson’s classification of objects, we divided
them into two patterns: detached and attached objects
related to the home’s room layouts (Table 1).</p>
      <p>In this prototype, 10 objects—a bathtub, cabinet, chair,
cushion, door, futon, sofa, table, threshold, and wall—were
extracted as the most frequently found everyday things in
the infants’ homes. Based on the longitudinal observation,
infants’ perceptions and actions toward these 10 objects
were observed and included not only positive
developmental possibilities but also risks of troubles—
positive and negative affordances for infants in the home.
Concrete examples of those affordances are described in
Table 2. These descriptions were embedded in the
application as reference for the app’s users. The users were
able to learn about a home’s contents according to three
categories: plan of room layout, attached objects, and
detached objects. Figure 2 is an example of a detached
object. The user can tap to select a category and items, and
pop-up windows show the properties of the object for
infants. The user can then tap the window’s close button or
swipe icons to see the next items.</p>
      <p>Regarding marker recognition, two types of
patternmarker codes (Figures 3 (a) and 3 (b)) were created. Figure
3 (a) was made by combining dots and objects’ icons using
OpenCV. Figure 3 (b) was made using textures and objects’
icons using OpenCV. The textures reflected the objects’
features.</p>
      <p>The AR system recognizes these markers’ codes from the
captured camera images. Both could be attached to
realworld objects at virtually no cost since the marker codes can
be printed using laser or inkjet printers.</p>
      <sec id="sec-3-1">
        <title>Overview</title>
        <p>Figure 4 introduces the overall information flow of the
system. The user begins by setting an arbitrary place marker
on the real objects in the real situation. After starting the AR
application, the user can capture the marker with his/her
device camera. As soon as the camera recognizes the marker,
the user can select the age of the actor. Then, the AR movie
starts to play (Figure 5).</p>
        <p>Each marker includes several AR movies based on
4–12month-old babies’ actions toward the object. Each movie is
color-coded according to the actor’s age. By selecting both
object and age, the user is able to discern the differences in
the infants’ developmental processes. The application
enables the user to simulate infants’ affordances toward
various objects in their own environments.</p>
      </sec>
      <sec id="sec-3-2">
        <title>User Experience</title>
        <p>Informal user observations formed the basis for this
prototype. These observations indicated that marker
recognition time is one of the most effective points to use in
the prototype development. We measured the velocities of
recognition time to compare two types of AR markers under
two lighting conditions: (A) fluorescent light and (B) flat
surface fluorescent light.</p>
        <p>Tables 3 (A) and 3 (B) show the rate of change of velocity
related to the illuminance of the surface (vertical and
horizontal directions) and the distance between marker and
device, in addition to the verified accuracy of marker
recognition via an illuminance meter. The findings revealed
differences between (A) and (B) of more than 30 cm. In the
case of the flat surface fluorescent light, the differences
depended on the surface direction (Table 3 (B)). On the
whole, (B) shows relatively unstable properties and more
effects of the surroundings than does (A).</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Discussion</title>
      <p>With this AR application prototype, users could put markers
on real objects anywhere there is adequate space to paste
them. This would make it possible to expand user
experience by increasing understanding of infants’ actions.</p>
      <p>The first years of life are filled with positive and negative
affordances that enable infants to develop. These
affordances could be changed according to age, motor skills,
or object layout. This AR application prototype provides an
opportunity to examine the relationship between infants and
their environments and to learn from it. Additionally, it
allows a more precise look at what may lead to accidents
within the app users’ own home environments. Moreover,
the prototype displays resources that may aid development
in the long run.</p>
      <p>The target users of this application are not limited to
young parents. Its popularity is expected to spread into the
educational, design, and cognitive science fields from the
context of ecological psychology.</p>
      <p>From a usability perspective, 1) the application’s UI/UX
aimed simple graphic design and standard gestures (tap and
swipe) functionality. The way of providing notification of
risk information and tips for development continues to
improve. 2) A marker-based system would currently be
more suitable for users in a variety of situations. It will also
be necessary to gather more data in the near future
concerning children’s actions by sharing this prototype. The
goal is to create an AR application global composition
system that will allow users worldwide to capture
augmented information about real, everyday objects
(furniture, door, steps, etc.) in their surroundings without
any markers.</p>
    </sec>
    <sec id="sec-5">
      <title>Acknowledgments</title>
      <p>This research was supported by the Japan Society for the
Promotion of Science (JSPS) KAKENHI (26870473),
Grant-in-Aid for Young Scientists (B).</p>
    </sec>
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