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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Multimodal AI Agent to Support Students' Motion-Based Educational Game Play</article-title>
      </title-group>
      <contrib-group>
        <aff id="aff0">
          <label>0</label>
          <institution>Norwegian University of Science and Technology</institution>
          ,
          <addr-line>Trondheim</addr-line>
          ,
          <country>Norway https</country>
          <institution>://lci.idi.ntnu.no/</institution>
        </aff>
      </contrib-group>
      <abstract>
        <p>Increased accessibility of lightweight sensors (e.g., eye trackers, physiological wristbands, and motion sensors), enable the extraction of student's cognitive, physiological, skeletal, and a ective data, as they engage with Motion-Based Educational Games (MBEG). Real-time analysis of this Multi-Modal Data (MMD) leads to a deep understanding of student's learning experiences and a ords new opportunities for timely, contextual, personalised feedback delivery to support the student. In this work-in-progress, we present the MMD-AI Agent for Learning; a MMDdriven Arti cially Intelligent (AI) agent based eco-system, composed of 3 separate software components, which work together to facilitate student's learning during their interactions with MBEG. The Crunch Wizard, receives MMD from eye-trackers, physiological wristbands, web camera, and motion sensors worn by a student during game play, and derives relevant cognitive, physiological and a ective measurements. The AI agent identi es and delivers appropriate feedback mechanisms to support a student's MBEG play learning experience. The Dashboard visualises the measurements to keep teachers informed of a student's progress. We discuss the foundational work that motivated the ecosystem's design, inform on our design and development accomplished thus far, and outline future directions.</p>
      </abstract>
      <kwd-group>
        <kwd>multimodal</kwd>
        <kwd>ed-tech</kwd>
        <kwd>arti cial intelligence</kwd>
        <kwd>motion-based games</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction and Motivation</title>
      <p>It is important to obtain a holistic understanding of student's educational
experiences in order to provide them with appropriate, constructive, timely and
personalised support during their interactions with learning activities. Current
practices typically rely on researcher's observation, surveys, interviews and
questionnaires. Though these methods have undoubtedly advanced our
understanding of student's educational experiences, their a ordances are limited to the
student's memories, and perceptions of what researchers can \externally"
observe. Additionally, data collected in this manner can only be analysed after the
learning experience has completed; thereby preventing opportunities to sca old
Copyright © 2021 for this paper by its authors. Use permitted under Creative Commons License Attribution 4.0 International (CC BY 4.0).
student's learning in real-time through provision of feedback mechanisms.</p>
      <p>
        In this regard, recent advancements in sensing technologies and their
respective Multi-Modal Data (MMD), demonstrate the capacity to transform how we
understand and conduct student's educational experiences. Speci cally,
MotionBased Educational Games (MBEG) utilise sensing devices (e.g., Microsoft Kinect)
to capture, map and interpret student's full-bodied movements as game input
[
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. These games have gained traction across a multitude of educational domains
in student's learning (e.g.,[
        <xref ref-type="bibr" rid="ref10 ref8">10, 8</xref>
        ]). Previous works suggests that compared to
traditional classroom instruction (i.e., pen and paper), the \touchless" nature of
MBEG o ers student a more engaging and natural learning experience [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ].
      </p>
      <p>
        In addition to motion sensing devices, wearables like eye-tracking glasses
and wristbands, allow for the unobtrusive, continuous, and automatic
collection of student's MMD generated during their learning experiences. Leveraging
the a ordances of MMD (e.g., temporality and direct access to indicators of
student's cognitive and a ective processes [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]), provides researchers with a new
vantage from which to observe and monitor student's \internal" states (e.g.,
cognitive, physiological) in real time [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ]. Thus, investigating the inherent
richness of student's natural interactions with MBEG by using MMD might enhance
our understanding of student's learning experiences [
        <xref ref-type="bibr" rid="ref13 ref14">13, 14</xref>
        ], and contribute to
the development of supportive measures (i.e., feedback mechanisms) which can
be integrated to student's educational technologies/experiences. However,
despite the potential of interlacing MBEG and MMD from sensing technologies,
limited research has explored the con uence of these ideas/domains to better
support/sca old student's learning experiences through automatic, personalised,
feedback generation/delivery.
      </p>
      <p>To bridge this gap, we are creating a MMD-driven Arti cially Intelligent
(AI) agent and visualisation dashboard ecosystem that: 1) collects and assesses
student's MMD during their interactions with MBEG, 2) identi es, prioritises
and delivers appropriate feedback mechanisms to sca old student's educational
game-play experiences in real-time, and 3) visualises the MMD for teachers to
keep informed on individual student's progress so that teachers can contextualise
this data with their own personal accounts of each student. In this paper, we
present our product vision, work completed thus far, and discuss directions of
future work.
2</p>
    </sec>
    <sec id="sec-2">
      <title>The MMD AI Agent Educational Ecosystem</title>
      <p>The purpose of this work is to create an MMD-driven AI educational sca olding
ecosystem, that automatically and continually, provides personalised feedback to
support student's learning during their interactions with MBEG. The MMD-AI
Agent for Learning consists of three components, the Crunch Wizard, a
Dashboard, and an AI agent (each described in section 2.2). Research, development
and validation of the MMD-AI Agent for Learning occurs in three consecutive
phase, where each phase builds on the previous results. In phase 1, we
augmented student's MBEG play with MMD collection devices to explore how the
collective data (i.e., gaze from eye-tracking glasses, physiological from wristband,
and skeletal from Kinect) might be used to understand and support student's
learning. In phase 2, we commenced the design and development of the MMD-AI
Agent for Learning, based on design implications that resulted from phase 1. We
are currently partway through phase 2; initial versions of the Crunch Wizard and
the Dashboard have been implemented, however, development of the AI agent
has not started. Lastly, in phase 3, we will conduct an empirical study to assess
the e cacy of the MMD-AI Agent for Learning, from the perspective of both
students and teachers. Each phase is detailed below.
2.1</p>
      <sec id="sec-2-1">
        <title>Phase 1: Discovering the possibilities of MMD and MBEG</title>
        <p>The purpose of this stage was to explore how MMD contributes to understanding
students' interactions with MBEG, and to identify ways to support students'
game play experience through real-time, personalised, MMD-driven feedback
mechanisms. To address this, we conducted a study in the winter of 2019, in
which students wore Tobii eye-tracking glasses and Empatica E4 wristbands, as
they played three commercial single-player MBEG from the Kinems Platform1
focused development of maths and language skills. The MBEG tracked student's
movement using Kinect.</p>
        <p>Context &amp; Participants: the study took place in a local science museum and
public elementary school in a European city. The designated study space was
arranged to accommodate two experimental set-ups running in parallel. Our
sample included 46 students (28F, 18M) with an average age of 10.3 years (SD
= 1.32, min= 8, max= 12 years). Sixteen students participated at the science
1 https://www.kinems.com/
centre, and 30 at the elementary school. No students had prior exposure to
MBEG. Students received a gift card in exchange for their participation.</p>
        <p>Procedure &amp; Data Collection: Each student was given a pair of Tobii
eyetracking glasses , and an Empatica E4 wristband to wear. They played 3 di
erent MBEG, 3 times each (9 sessions total). Student participated in a practice
session where experimenters assisted them in understanding the game's rules
and objective. The cumulative play time of all 9 sessions ranged between 25-30
minutes. We collected sensor data from: Tobii eye-tracking glasses , Empatica
E4 wristband (with sensors for HRV, blood-pressure, temperature and EDA
levels), Microsoft Kinect (which tracked skeletal movement of 25 di erent joints),
and Logitech web camera. We also screen recorded student's game sessions,
examined their system logs (e.g., for speci c event occurrences) and monitored
in-game performance metrics (i.e., reaction times, game score). Figure 1 shows a
student in action, wearing the data collection devices, together with
experimental set up. Table 1 presents the measurements that were derived from the raw
MMD.</p>
        <p>
          Results: We analysed the data according to several research questions, but
limit our presentation of results to only those which motivated, and are included
in the design of, the AI agent discussed in Phase 2. Speci cally, our results
suggested the following possibilities (references concealed to preserve anonymity).
Problem Solving and Play: we examined the possibility of using MMD
measurements derived from student's interactions with MBEG, to determine
when students are 1) playing rather than problem solving, and 2) guessing
rather than taking an informed decision [
          <xref ref-type="bibr" rid="ref11 ref12">11, 12</xref>
          ].
        </p>
        <p>
          Prediction: the combination of gaze and physiological measures (from
eyetrackers and wristband, respectively), can be used to predict student's
ingame performance metrics (where performance is measured by correctness
of answers). Prediction occurs with extreme accuracy (i.e., 94%) in a short
amount of time (i.e., 47s) [
          <xref ref-type="bibr" rid="ref13">13</xref>
          ].
        </p>
        <p>Prioritisation: relative to the student's correctness of answer (history of right
or wrong) during MBEG play, we developed a novel MMD measurement
classi cation scheme and corresponding algorithm which may be used
together to prioritise the delivery of di erent (and possibly con icting) types
of feedback when multiple avenues of support are applicable for
addressing the needs of di erent MMD measurements. We have broadly identi ed
di erent types of feedback (e.g., scaling of content di culty, o ering hint,</p>
        <p>
          informing the teacher to interact with the student in a speci c manner,
removal or inclusion of game distractors) corresponding to the di erent MMD
measures. In practice, the exact realisation of each feedback type must be
contextualised and thus, will largely depend on the focus of the MBEG [
          <xref ref-type="bibr" rid="ref16">16</xref>
          ].
2.2
        </p>
      </sec>
      <sec id="sec-2-2">
        <title>Phase 2: Realising the MMD-driven AI ecosystem</title>
        <p>Building on the above results, we designed and have started developing the
MMD-AI Agent for Learning, purposed to provide students with personal,
contextualised, real-time support delivered either in-game or from their teacher, as
they interact with the MBEG. MMD-AI Agent for Learning consists of MMD
devices (i.e., Tobii eye-tracker, Empatica E4 wristband, Logitech webcam, and
Microsoft Kinect) and three software components; namely, the Crunch Wizard,
Dashboard, and AI agent.</p>
        <p>How it Works: the MMD-AI Agent for Learning works as follows. A student
wears Tobii eye-tracking glasses and an Empatica E4 wristband as they interact
with a MBEG. Throughout their game play, the student's raw MMD (gaze from
eye-tracker and physiological from wristband) is continuously collected by the
devices and sent to the Crunch Wizard program in real-time. Skeletal and video
data are sent by the Kinect and Logitech webcam, respectively. The Crunch
Wizard calculates measurements from the raw MMD, writes the measurements
to a database, and sends them to the AI agent and the Dashboard. The AI agent
assesses the student's measurements, in conjunction with in-game performance
metrics sent from the MBEG, and determines whether the student requires
support. If so, the AI agent determines the appropriate feedback mechanisms and
mode of delivery. Feedback in the form of suggestions for the teacher, may be
sent to Dashboard. Feedback may also be realised as in-game student support.
The Dashboard visualises the incoming measurements according to the teacher's
preferences (e.g., speci cally selected students and measurements), as well as a
noti cation centre where the teacher may receive feedback alerts indicating
appropriate ways to sca old the students experience.</p>
        <p>The system can be used by a single student, or multiple students
concurrently. In the case of multiple student's, each must participate from separate
learning environments, such that they have access to their own eye-tracker,
wristband, web camera, and MBEG. Each separate setup includes its own Crunch
Wizard and AI agent program instances. However, all instances of Crunch
Wizard and AI agent, pass their data to a single shared Dashboard. A student's
Crunch Wizard and AI agent must be running on the same machine, but due
to the decoupled nature of the software components, the Dashboard is able (but
not required) to reside on a di erent machine, at a separate physical location.
Thus, the MMD-AI Agent for Learning enables remote educational instruction,
where each student interacting with a MBEG, and a teacher monitoring their
learning experience (via MMD measurement viewed on the Dashboard), can
participate from their separate locations. Figure 2 shows an overview of the
MMD-AI Agent for Learning, together with the MBEG, and directional ow of
data (raw MMD, derived measurements, in-game metrics) and feedback
mechanisms. Following, we provide a detailed account of each software component:
Crunch Wizard, Dashboard, and AI agent.</p>
        <p>Crunch Wizard receives an in ux of raw MMD (i.e., gaze, physiological,
and skeletal) sent from the devices (Tobii eye tracker, Empatica E4 wristband,
Logitech web camera, and Microsoft Kinect) worn by a student during game
play throughout their learning experience, and calculates various
corresponding MMD measurements (see 1). Since the devices monitor a student's state
(e.g., HR, eye and joint movement), new data is continuously sent to Crunch
Wizard, and corresponding new measurement updates are constantly calculated
and propagated to the dashboard and AI agent. The current iteration of Crunch
Wizard calculates the following measurements from incoming raw MMD:
physiological stress, physiological arousal, engagement, emotional regulation, perceived
di culty, anticipation, cognitive load, information processing index, emotions,
fatigue, motion stability.</p>
        <p>Dashboard visualises students' MMD measurements in real-time, to help
teachers know what necessary action they should take to improve the learning
process of individual students. A future iteration will display recommendations
to guide the teacher in providing appropriate feedback to speci c students to
support their learning session in real-time. The feedback recommendations come
from the AI agent and are discussed in the following text.</p>
        <p>When the teacher enters the dashboard, they are prompted to ll out a form
to create new learning session (see Figure 3a). The teacher enters a session
name, and selects a student to participate. To add a student, they must have
a learner pro le. If no pro le exists, the teacher must create one (by clicking
the yellow + button). Each learning session has a unique session code, that is
used to connect the student's software components (Crunch Wizard, and AI
agent) to the teachers dashboard. After a connected has been established, the
teacher is able to select between an \all sessions view" and individual session
(a) View of new learning session and stu- (b) View of a single student's learning
sesdent pro le creation. sion.
(c) View of multiple student's learning (d) View of a student's recorded learning
sessions for measurement comparison. session.
views for each student. The all session view shows data for every participating
student, whereas the individual student views allow the selection of any number
of participating students. Figure 3b shows a live learning session view for a single
student, Erland.</p>
        <p>The teacher can customise which measurements (from those listed in the
Crunch Wizard section) they wish to view during the learning session. This
allows the teacher to assess the student's learning experience based on
specifically selected metrics. If viewing multiple students, the teacher can identify,
and direct their attention, the students that require additional support with the
knowledge of where they are struggling. For example, a teacher may wish to
examine the perceived di culty and information processing index of two
participating students, Erland and Lukas (see Figure 3c). Perceived di culty is the
level of di culty the student attributes to the question. Thus, in seeing that
Erland is experiencing the problem as harder than Lukas, the teacher can pay
special attention to Erland's progress and support him if he appears to be
struggling.</p>
        <p>The Crunch Wizard is responsible for sending student's MMD measurements
to the dashboard, and recording this the data in a database. The dashboard
supports viewing learning sessions after a learning session has nished. The teacher
can set the time interval they wish to view, which controls how much of the
learning sessions data is shown on each measurement's selected graph. Figure
3d shows 34s of data for a single student's learning session (as set by the yellow
slider on the top right). Viewing and comparison of multiple learning sessions
belonging to the same student, or multiple students, is also possible.</p>
        <p>AI agent orchestrates feedback delivery to sca old the student's learning
experience. It receives a continuous ow of real-time data from both the MBEG
(e.g., the student's in-task performance metrics) and Crunch Wizard (e.g., MMD
measures), collectively assesses the student's measurements, determines the
appropriate feedback mechanisms required to facilitate the learning experience (if
needed), and delivers the feedback accordingly. The type of feedback to deliver is
determined by a combination of a student's performance prediction results, the
MMD measurements classi cation and prioritisation algorithm, and play and
problem solving design implications, derived from our previous publication, as
mentioned above. The feedback is realised in numerous ways (i.e., in-game hints,
scaling of content di culty, informing the teacher that help is needed),
according to the student's individual MMD measurements and in-game performance
metrics. Moreover, feedback is provided either directly to the student through
modi cation/supplementation of game content (e.g., scaling down content
difculty in response to elevated cognitive load or perceived di culty), or to the
teacher via the visualisation Dashboard (e.g., informing the teacher to
encourage the student) so that they can use their personal knowledge of the student
to determine a contextualised appropriate course of action. Thus, the AI agent
must maintain a bi-directional stream of communication with both the MBEG
and the Dashboard, but only receives data from the Crunch Wizard (see Figure
2). In order to enable the provision of feedback directly to the child through
modi cation on the game content, the AI agent must communicate with the
MBEG engine. In our rst iteration of the AI agent, we will adapt, and connect
directly to, the game engine for the Kinems Platform utilised in our study
presented in Phase 1. Future versions will focus on developing the AI agent into a
software SDK for easy integration into MBEG during their development phase.
Development of the AI agent has not yet commenced.
2.3</p>
      </sec>
      <sec id="sec-2-3">
        <title>Phase 3: User Testing</title>
        <p>Thus far, the current version of the MMD-AI Agent for Learning (i.e., Crunch
Wizard and Dashboard, without AI agent), has undergone a single user test
with an adult acting as a teacher (though not a teacher). The motivation
behind the usability testing was to identify issues with the Dashboard layout and
functionality. Therefore, there was no need to include students playing a MBEG.
Rather, the test was consulted remotely, with a researcher wearing the devices
while web camera was capturing their movement. The test subject navigated to
various views within the Dashboard during this experience, and was asked to
identify and interpret di erent information on-screen. Test data was collected
via video/audio recording and System Usability Scale (SUS) survey. Results
indicated that there there was confusion related to recording, and viewing of
recorded, data (as discussed above in the Dashboard section and shown in
Figure 3d). Upon completion of development and integration of all three software
applications (Crunch Wizard, Dashboard, and AI agent), the MMD-AI Agent
for Learning will be extensively tested by teachers to assess its usability, and
likelihood of class-room adoption. We require relevant test tasks (i.e., the
system will be tested using the MBEG from the Kinems Platform), subjects (i.e.,
both teachers and students), and environment (i.e., in class-room).
3</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Future Work and Conclusion</title>
      <p>In future, we aim to extend the MMD-AI Agent for Learning to accept data from
a stationary eye-tracker. Upon creation of a learning session, either the teacher
would input or the system would detect, which eye-tracker a given student will
use during their learning session. This will allows a student to sit directly in
front of a computer screen which supports traditional computer-based
learning experiences (e.g., non-motion based). A driving factor for augmenting the
eye-tracking capabilities of the system, is to promote inclusion of students with
limited mobility. Additionally, this would also enable future studies which
compare traditional computer-based learning games with their motion-based counter
parts. The Kinems Platform is a favourable candidate for this endeavour, as it
includes learning games that are o ered in both motion and non-motion -based
form. Our work contributes to the understanding of multi-sensor devices
\beyond mouse and keyboard" in learning contexts with the purpose of automatic
feedback generation, adaptation, and personalisation in student's learning, and
good graphical visualisation of quantitative information, to make the learning
processes more measurable and interpretable.</p>
    </sec>
  </body>
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