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    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>A Study on Skill Acquisition Mechanism and Development of Skill Transfer Systems</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Hideki Koike</string-name>
          <email>koike@acm.org</email>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Jun Rekimoto</string-name>
          <email>rekimoto@acm.org</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Junichi Ushiba</string-name>
          <email>ushiba@brain.bio.keio.ac.jp</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Shinichi Furuya</string-name>
          <email>furuya@csl.sony.co.jp</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Asa Ito</string-name>
          <email>ito.a.ah@m.titech.ac.jp</email>
          <xref ref-type="aff" rid="aff3">3</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Keio University</institution>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Sony Computer Science</institution>
          ,
          <addr-line>Laboratory</addr-line>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>The University of Tokyo</institution>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>Tokyo Institute of Technology</institution>
        </aff>
      </contrib-group>
      <abstract>
        <p>This paper describes our project which studies skill acquisition mechanism and develops skill transfer systems. To clarify skill acquisition mechanism, we analyze top athletes, elite music performers and handicapped persons who have advanced skills which are not found in ordinary people. Then we will develop skill transfer systems by using advanced computer vision, robotics and artificial intelligence.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>INTRODUCTION
Human augmentation is regarded as an important research
field with a view to the future society in which computer
technology, artificial intelligence technology, robot
technology, etc. are highly integrated. There is a powered suit such
as HAL1 by CYBERDYNE Inc. as a representative human
augmentation technology. This is used to carry heavy objects
that human cannot possess or to complement the lost body
functions due to injuries and diseases. However, too much
dependence on such complementary technologies may worsen
human’s physical ability and cognitive ability. In other words,
there is a need for a human augmentation that can strengthen
human’s ability regardless of healthy persons or persons with
disabilities. Of course, application to strengthening
physical ability of powered suit is also conceivable, but many of
the conventional orthotics are mechanical type or those
using McKibben type artificial muscle. However, they are not
suitable for teaching sensitive delicate movements.</p>
    </sec>
    <sec id="sec-2">
      <title>1https://www.cyberdyne.jp/english/products/HAL/</title>
      <p>⃝c 2018. Copyright for the individual papers remains with the authors. Copying
permitted for private and academic purposes.</p>
      <p>
        SymCollab ’18, March 11, 2018, Tokyo, Japan
The conventional augmented reality system displays
superimposed virtual worlds in the real world. In acquiring skills,
it has been pointed out that not only such simple additional
information display but also an augmented reality system in
which people see themselves from the outside in a
thirdperson’s view [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] is effective. Also, there are many cases that
the motion is so fast that visual feedback is not appropriate.
In this case, it is necessary to integrate other sensory channels
such as auditory sense, tactile sense, and haptic sensation and
to provide teaching data in multi-channel.
      </p>
      <p>The advanced skills of elite music performers, top athletes,
disabled people are acquired by many years of training and
experience. It is difficult to externalize such skills, and
therefore it is difficult to transfer the skills to others. For example,
in sports science, it is possible to measure body motion using
the latest equipment such as special video equipment, small
sensors, etc. However, the feedback to the athlete is limited
to video playback after training and presentation of the
measurement data. It is desirable that the coach intervenes in real
time during training, and teach how to use the body, gaze
direction, or psychological guidance etc. However, it cannot be
done because (1) the essence of skill is not understood, (2) the
difference with others is unclear, (3) it is difficult to present
differences in real time using haptic tactile awareness during
exercise.</p>
      <p>In this project, we aim to develop the foundation of the
technology of skill acquisition support system that acquires (i.e.
copies) advanced skills from people and transfers (i.e. pastes)
them to others using advanced image processing technology,
augmented reality technology, robotics technology, and
artificial intelligence technology. To that end, it is first necessary
to clarify the principle of skill acquisition mechanism.
Therefore, we analyze elite musicians, elite athletes and disables
people those have special skills that are not found in ordinary
people. We try to abstract the essence of skills by reducing the
dimension of the multidimensional big data obtained by using
statistical and machine learning methods. On the other hand,
it was difficult to transfer skills until now because it is
difficult to measure gaze, body movement, environment in real
time, without disturbing the free and natural movement of
humans. In order to solve this problem, we develop the
following skill acquisition support system in this project. The first
is a wearable gaze, body motion and environment
recognition device using a small omnidirectional camera. The
omnidirectional camera shoots an entire scene including human’s
face, body and environment. By applying image stabilization,
feature extraction, machine learning to this omnidirectional
video, recognition of gaze, body motion and environment is
achieved at the same time. The second is a device for
presenting third person’s view using a compact HMD. Based on the
body movement and the environment recognition, real-time
feedback is provided based on the difference between model
data and the body movement. The third is a real-time force
feedback device using ultra-fine artificial muscles.
Conventional force presentation devices were mechanical type like
CYBERDYNE’s HAL or McKibben type artificial muscles,
which hindered users’ natural and free movement. In
contrast, we develop a lightweight, wearable haptic feedback
device using ultra-fine artificial muscle. Teaching data is
presented to the user in real time. Ultimately, we validate the
effectiveness of each developed device by applying it to each
field of music performance, sports, disabled persons and
rehabilitation.</p>
      <p>PROJECT DESCRIPTION
In this research, we mainly focus on two research themes:
(1) abstraction of skills and clarification of skill acquisition
mechanism, and (2) development of skill acquisition support
technology. Both are done in parallel, but scientific
knowledge in (1) is fed back to (2). Also, the prototype of the
acquisition support system developed in (2) will be provided in
(1) and will be used for new experiments to clarify the skill
acquisition mechanism.</p>
      <p>A study on skill acquisition</p>
      <p>
        Biomechanical study on top athletes
Data accumulation and analysis of top athlete skills will be
conducted. Motion measurement, gaze measurement, etc.
for specific sports are performed. Obtained data are
multidimensional time series data. We apply principal
component analysis (PCA) and machine learning to extract the
essence of skills. At the same time, we will develop a
gaze, body motion and environment recognition device
using a small omnidirectional camera. The image
stabilization method [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] is applied to the obtained omnidirectional
video. Then, we will perform gaze estimation and
motion recognition by using deep learning algorithms such as
OpenPose library [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], and also perform environment
recognition by SLAM [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ].
      </p>
    </sec>
    <sec id="sec-3">
      <title>Cognitive study on handicapped person</title>
      <p>In order to master artificial limbs, we need to acquire
another body control sensation different from that when
not wearing. This process of acquiring shifts from
“conscious control” to “unconscious control (automatic
control)” along with proficiency. However, depending on
physical condition and specifications or prosthesis,
unconscious control goes back to conscious control. It is
important to know how the prosthetic user gains and
distinguishes multiple body senses. We analyze what kind of
cause exists in handicapped persons through interviews.
The findings obtained here not only include implications
for support of people with disabilities but also help to
clarify the promoting factors and inhibiting factors when the
human body wears artificial objects such as artificial
devices. Also, in the human augmentation technology, it is
possible to think of situations where a person and a person
actively interact through artifacts.</p>
    </sec>
    <sec id="sec-4">
      <title>Study on rehabilitation</title>
      <p>
        We will develop “visual reprogramming glasses” that can
integrate HMD with the omnidirectional gaze motion
measuring device developed in other groups and program the
visual characteristics of the subjects [
        <xref ref-type="bibr" rid="ref5 ref8">8, 5</xref>
        ]. In addition,
we develop a “haptic reprogramming device” which can
change the motion resistance by incorporating a magnetic
fluid active joint whose viscosity can be controlled to the
brace attached to the wrist joint or the elbow joint. We will
use “target/reaching experiment” to adjust the fingertip to
the target position. As described above, by mathematically
modeling the adaptation process of the brain that occurs
when modulating the physical environment information at
a strength that is not conscious using a wearable visual
presentation device or a force sense presentation device. We
formulate a general extension law that is not dependent on
generality.
      </p>
    </sec>
    <sec id="sec-5">
      <title>Study on elite music performers</title>
      <p>
        We will clarify elite musician’s skills and biological
information processing behind them [
        <xref ref-type="bibr" rid="ref3 ref7">3, 7</xref>
        ]. Firstly, we will
target professional pianists in college of music and perform
’archive of transcendence skill’ to measure the movement
and muscle activity of various bodily skills. Therefore, we
develop a sensing system detachable to the instrument and
high precision data glove. Secondly, using the
multivariate analysis such as NMF and LASSO regression and deep
learning, we extract individual skills based on the obtained
big data.
      </p>
      <p>Development of skill transfer system</p>
      <p>
        A tactile feedback suit using ultra-fine artificial muscles
Tactile feedback is very important for actual skill
transfer. In this study, we develop a lightweight tactile feedback
suit incorporating ultra-fine artificial muscle [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. This is an
ultra-fine artificial muscle with a diameter of about 2 to 4
mm, it is possible to make a suit that does not disturb free
movement by sewing into clothes. We have already
conducted preliminary experiments using this artificial muscle
and confirmed that sufficient torque can be obtained with
a small number of artificial muscles by devising a knitting
pattern. We will first develop a device that can be worn on
the arm, and then develop upper body or whole body suit.
      </p>
    </sec>
    <sec id="sec-6">
      <title>A system providing third person’s view</title>
      <p>In order to acquire body control ability, it is effective to
provide means for seeing learner’s body from the third
person’s view. In addition, we think that it is effective to
provide means for providing the difference between the
physical condition of the user and the model. For this purpose,
we develop a system that projects its own body image in
front of himself by augmented reality and emphasizes the
difference with the model image as a model. Furthermore,
a tactile feedback device is arranged on the body surface
of the learner so that the difference portion can be
experienced not only by sight but also by tactile sense. In order
to present the difference in a more comprehensible manner,
a method of compressing multidimensional information of
the skeleton shape with a neural net (e.g. auto encoder,
etc.) will be studied.</p>
    </sec>
    <sec id="sec-7">
      <title>Future prediction</title>
      <p>Excellent athletes and performers are expected to predict
the event occurring at the next moment from the current
exercise condition and the environmental recognition
result. Also, in rehabilitation, if it becomes possible to
predict accidents such as falling of a practitioner in advance,
measures such as supporting the principal can be taken. For
this reason, time series measurement information including
human body shape displacement and barycentric position
change etc. is learned and predicted using Recurrent
Neural Network. In combination with a force feedback system,
an injury prevention interface can be constructed.
DISCUSSION
The first scientific impact expected from the project is a
recognition method of gaze, body and environment using
omnidirectional video. This will open up a new field of computer
vision including a new image stabilization method, gaze
estimation method by deep learning and three-dimensional body
shape restoration. The third person’s view system requires
advanced image processing technology and real-time image
synthesis technology, and creates a new augmented reality
study. The force sense presentation system proposes a new
way of using ultra-fine artificial muscle and it is expected to
be applied to the field of robotics. Also, externalization of
skills makes it possible to discuss skills scientifically.
From the viewpoint of creating new industries, cyber
training systems for players and athletes, support devices for
persons with disabilities, and rehabilitation systems will be
developed. In particular, a third person’s view system and a
force feedback system using ultra-fine artificial muscles
becomes a new technology in HCI.</p>
      <p>As a social contribution, this project contributes not only to
the transfer of skills, but also to the realization of a
society where healthy people and disabled people coexist, and
contribution to the elderly problem can be considered. At
the same time as supporting the maintenance of the physical
health of the elderly, by lowering the threshold of acquiring
the musical instrument performance, it is possible to give the
living worth of hobby and also to prevent dementia by fine
finger movement. Human augmentation technology is
ubiquitously invoked for everyday life at elderly care facilities and
at home, realizing a human-machine coexistence life that
prevents, maintains, and strengthens declines in physical ability
and cognitive ability.</p>
      <p>CONCLUSION
In this paper, we described our project of a study on skill
acquisition and skill transfer. By using augmented human
technology which integrates computer vision, robotics and
artificial intelligence, we aim to develop a framework and systems
to support humans collaborating with embedded
environmental intelligence.</p>
    </sec>
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