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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>St. Pölten,
Austria</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>Embodied Material Guidance: Augmenting Material for Carving</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Marcel Penz</string-name>
          <email>marcel_penz@hotmail.com</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Sreyan Ghosh</string-name>
          <email>contact@sreyan.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>National Institute of Design, India, R &amp; D Campus</institution>
          ,
          <addr-line>Bangalore 560 022, Karnataka</addr-line>
          ,
          <country country="IN">India</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Umeå Institute of Design, Umeå University</institution>
          ,
          <addr-line>SE-90187 Umeå</addr-line>
          ,
          <country country="SE">Sweden</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2016</year>
      </pub-date>
      <volume>2</volume>
      <fpage>4</fpage>
      <lpage>11</lpage>
      <abstract>
        <p>When learning a new skill, video tutorials are often the first choice to get help. For creative domains like carving, this is often not sufficient as the desired expression require reacting on changes in the form constantly. A crucial part of the making process is a close observation of the material. Looking at various domains we have chosen wood carving, to propose new forms of interactions that can support creative learning processes. Instead of focusing on tools we aim to augment the material for the novice carver. The concept aims to reduce the fear of learning by replacing traditional carving material (like wood) with 3D printed material. Guides on where to carve are part of the printed base material and form embodied guidance. We assume artistic self expression as an additional goal for carving and provide added levels of randomness to the material structure through variable colors and material densities while using Virtual Reality (VR) to provide a change in perspective.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        1 Introduction
The success of numerous online tutorials for making
indicates how people gather first hand insights in
learning a new skill. Free online platforms for learning
such as edx.org, coursera.org or others offer a variety
of courses for both hands-on and theoretical
knowledge building conveyed through video. Often
tutorials allow for copying a stepwise process to
achieve a certain goal. For artistic activities like
painting, clay modelling or wood carving static videos
– which don’t adapt to the learner’s context – are only
of limited help. For painting different interactive
systems have been created that have the potential to
support the learner by enhancing brush and/or canvas
by digital components (
        <xref ref-type="bibr" rid="ref5">Otsuki et al., 2010</xref>
        , Vandoren
Copyright © by the paper’s authors. Copying permitted only for private
and academic purposes.
      </p>
    </sec>
    <sec id="sec-2">
      <title>2.1 Ideation Workshop</title>
      <p>In order to better scope the project we invited design
students to participate in an ideation workshop
revolving around the question of how the future home
can be a place for collaborative making and learning
through making. During the 45 min workshop, six
students of the Master’s programme in Interaction
Design at the Umeå Institute of Design were asked to
follow a set of tasks involving reflecting on hobbies
and their tools and how the tools will change in the
future. Some participants found it difficult to force
features onto tools that should enable creativity.
During the final discussion a common point of view
was created stressing that tools should be enablers
rather than means for creativity. By not focussing on
the tools we were inspired to think about the material
instead. Hence we decided to take an approach of
augmenting the medium i.e, the carving material.</p>
    </sec>
    <sec id="sec-3">
      <title>2.2 Research on Tutorial Videos for Making</title>
      <p>
        To identify the issues that the hobbyist carver faces, we
reviewed tutorial videos on the web
        <xref ref-type="bibr" rid="ref2 ref7">(Farnsworth, 2014,
Schrettl, 2014)</xref>
        trying to place ourselves in the mindset
of a beginner in that field. Our reflections towards
these videos helped us identify a few issues. When
staying in the virtual world, support through video
seems to work effectively e.g. for digital tools such as
creative software (Photoshop, 3DS Max). We assumed
that the flat representations on the screen perform
inadequately when it came to learning with actual
tangible material. Videos are sufficient for defined
tasks or step-by-step instructions. However, videos do
not work as well for artistic expression such as carving
due to the fact that the material in the user’s hand will
always be perceived differently than the one displayed.
The biggest challenge for the novice carvers seemed to
be in the ability to understand when to stop carving.
3 Concept
“Every block of stone has a statue inside it and it is the
task of the sculptor to discover it” — Michelangelo
Buonarroti.
      </p>
      <p>In the same way a blank page can be a barrier for a
writer a block of wood can be an issue for a sculptor.
Once this issue is overcome, the process of turning this
block of wood into a small figurine without using
machinery requires both craft skills and skills for
creative expression. In our concept we propose using
3D printing to create a specialized base material for
carving embodied guidance. In this way we want to
guide the carver towards a shape that is already part of
the carving block and foster a dialog with the carving
material through this augmentation. In addition we use
VR as part of supporting creative reflection.
3.1 Scenario
The user is inspired to carve out the iconic Swedish
Dala horse (Swedish: Dalahäst) and downloads or
builds her own CAD model (see fig. 1.1). In a software
similar to current 3D printing software, she imports the
model that is embedded in a virtual cube (see fig. 1.2).
Control elements let her choose how much of the horse
should be visible when later cutting through the
material. This is defined through 1.), contrast in color
between the horse and the waste material and 2.)
through guiding dots aligned with the edge of the horse
(see fig. 1.2a, 1.2b and fig. 2). The user should also be
able to add additional color gradients (see fig. 1.2a). A
sensor unit is embedded in the print, able to
communicate with a VR headset. After the block is 3D
printed (see fig. 1.3) she can carve the print
immediately (see fig. 1.4). The more she cuts, the more
guiding dots appear making her aware where to carve
away more material. As the color of the material
changes while cutting she is inspired to modify the
final shape for aesthetic reasons. To achieve a better
understanding of the proportions of the object inside,
she can use the sensor unit in her workpiece to connect
to VR headset using wireless technology. By switching
to VR she gets to see her work from a different
perspective (see fig. 1.5).
3.2 Embodied Guidance: Guiding Dots, Color
Gradients and various Levels of Material Density
When creating a drawing people use techniques like
tracing paper as support. The supporting techniques for
a novice carver creating 3D shapes are limited. Often
carvers draw guiding lines on the workpiece that are
carved away immediately, hence using 2D solutions
for a 3D problem. When interviewing makers we
discovered that – especially for beginners – there is
often the fear of carving away too much from the
carving material. By printing guiding dots in the base
material, drawing lines becomes obsolete and
confidence is fostered. As the novice carver starts to
carve out the printed block, a visual imprint of the
horse inside the block emerges. This acts as feedback
that helps the carver to stop carving in time, thus
overcoming the challenge of carving in too deep.
Further for intermediate users we envision various
levels of support by limiting the guides indicating the
border of the shape adjusted in software (see fig. 2,
center image). In this way we aim to support the
learning process. We also envisioned embedding a
color gradient changing the color from a surrounding
boundary box to the object inside. When the novice
carver sees the change in color, she is made aware that
the enclosed object is starting to surface (see fig. 2,
right image). Other ways of showing when the carver
gets close to the object could be to use variable
densities of material, a property that can be set for 3D
printers. By increasing the density of the object inside
(the Dala Horse) as compared to the surrounding
carving block tactile feedback can be provided.</p>
      <sec id="sec-3-1">
        <title>3.3 Creative Reflection on the Material</title>
        <p>We focus on the relationship between the user and the
material, almost trying to allow for a reflective
conversation, where the material provides rich
feedback on how it is treated. To achieve this, we
propose change in material through adding randomness
in the color gradients and providing the option to
change perspective in VR.</p>
      </sec>
      <sec id="sec-3-2">
        <title>3.3.1 Fostering Creativity by adding Randomness</title>
        <p>As described before guides can be printed in form of
guiding dots or color gradients. However the guiding
color gradient doesn’t have to be linear. By enabling
the user to add gradient turbulences, the embedded
object becomes slightly distorted. A low level of color
turbulences will lead to uniform coloring. Higher
levels of turbulences will cause multi-color 3D
gradient patterns (see fig. 3). In the same way material
density could change as well. This is an attempt to
mimic natural material qualities characteristic to wood.
The same way the wood’s growth direction can inspire
the wood carver to carve different shapes, artificial
randomness can hint towards a shape that the creator
has not thought of before.</p>
      </sec>
      <sec id="sec-3-3">
        <title>3.3.2 Changing Perspective: Using Virtual Reality</title>
        <p>In a last step we experimented with the virtual
representation of the initial shape using VR. A good
practice in (abstract) painting is to physically step back
from the painting to see how the latest brush strokes
have changed the overall composition. It is a state of
observation and reflection that allows for constant
acting and reacting on the painting. Other than this
example of a two dimensional canvas, the 3D object
allows us to explore the material also from the inside.</p>
        <p>With the help of a virtual reality headset the user
can place herself inside the box with the object in front
of her. This makes her aware of the parts that are not
carved out yet and may open up for changing the
direction she wants to pursue. By adding a small
inertial measurement unit (IMU) the workpieces
orientation can be tracked and transmitted to a VR
headset using wireless technology. The physical model
acts as controller for the user to navigate in 3D space,
where the user can move around the virtual
environment by moving the physical object (see fig. 4).
We created a prototype in Unity &amp; Arduino to
communicate ways to navigate in virtual space and
presented it to people (see next section). Since the user
holds the partially carved out object in her hand she
gets rich tactile feedback while at the same time seeing
the model from the inside. This disruptive experience
might encourage the user to change the way she thinks
about the workpiece. After establishing the experience
of the inside view, the user will return to the physical
world continuing to carve, having the possibility to
revisit the virtual space at any time during the process.
4 Evaluation &amp; Reflection</p>
      </sec>
      <sec id="sec-3-4">
        <title>4.1 Interviews</title>
        <p>We proceeded to interview four makers to gain
qualitative feedback on our concept. The interview
participants were chosen based on their background
and skill in craftsmanship. We interviewed a teacher
for making physical prototypes, a product design
student and passionate maker, a prototyper in a design
consultancy who likes to tinker in his free-time, and an
owner of a 3D printing shop. The participants were
asked questions around their personal experience with
making at the beginning of each interview. Some
recurring topics in all the conversations were:</p>
        <p>Sources of inspiration and the reason for making
including: Solving a specific problem through making,
inspiration by different materials or inspiration through
finding interesting projects (online). We also learned
that the tool plays different roles for different people
ranging from being the center of the activity to being
mere means to achieve a goal. Lastly we got to know
different drivers for making that can either be outcome
driven vs. process driven as well as making as
purposeful vs. making as artistic expression. Especially
the distinction between drivers has implications for our
design, as our concept is not meant to focus on creating
to fulfill a need but is a learning tool for expression in
3D physical objects. When presented with the concept
the interviewees saw great value in the material having
an embodied object and agreed that the concept could
definitely work to train and encourage people to carve.
The concept of variable gradients as a guide to stop
carving and start sanding was highlighted positively.
While the prototyper and the product designer saw
value in using VR to gain a different perspective, the
teacher did not agree and stated that the shift in
medium causes disconnect and the user should not be
made to leave the material at any stage of the carving
process. The print shop owner suggested that the
density of material should also vary along a gradient
along with the colors.</p>
        <sec id="sec-3-4-1">
          <title>4.2 Technical Limitations</title>
          <p>
            Adding the virtual reality feature would lead to
multiple problems. The first one concerns the sensor
unit embedded in the work piece. To our knowledge it
is currently not possible to print the sensor at the same
time as the carving block. One way to work around this
could be to add the electronics manually in the printing
process. The second problem is the changing shape of
the module that cannot be tracked easily with available
sensor technology. However research in this direction
has already been conducted
            <xref ref-type="bibr" rid="ref6 ref8">(Reed, 2009, Smith,
Thomas &amp; Piekarski, 2008)</xref>
            .
          </p>
          <p>
            To our knowledge there is currently no material
available that supports carving. However, when
interviewing an 3D printing expert he felt confident
that this material could be manufactured easily. Also
research suggests that this kind of material can be
produced
            <xref ref-type="bibr" rid="ref1">(Compton &amp; Lewis, 2014)</xref>
            .
          </p>
        </sec>
        <sec id="sec-3-4-2">
          <title>4.3 Beyond Carving</title>
          <p>We feel confident that there are advantages in
augmenting material by adding additional information
as part of the manufacturing process. Changes within
the material can provide extra information e.g.
considering abrasion and wear of material or inside
predetermined breaking points. We hope that this
concept inspires others to explore new possibilities on
how to physically augment material.
5 Conclusion
In this paper we present a concept to support novice to
intermediate skilled people interested in carving. As a
main incentive to carve we assume artistic self
expression and the learning/ skill building of carving as
handicraft. Our proposal focuses on the dialog between
the learner and the material and how the material can
be augmented to be more expressive. We show this in
three parts of our concept: First, the materialization of
guidance manifested in a 3D printed block (embodied
guidance). This allows the user to fully concentrate on
the material and the learning process. The embodied
guides aim to reduce fear of making mistakes and to
encourage training, since the final product is already
part of the workpiece. Second, to support for more
creative exploration of the material we envision the
functionality to change the inner structure (color
gradients and density) of the material by adding
randomness. Both embodied guidance and the creative
reflection with the material allow learning how to
carve by making use of the digitally enhanced material
while staying in the physical world interacting with it
in a tangible way. Third, we offer a way to use the
digital realm for changing the perspective to see inside
the physical workpiece using VR. We created
prototypes used in discussions with four makers. In
those discussions we found that the makers were
generally enthusiastic regarding various levels of
support and they could see value in random changes of
the material structure. However, not everyone agreed
on the importance of switching between VR and
physical world while carving.</p>
        </sec>
      </sec>
    </sec>
  </body>
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