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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>April</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>Pragmatic and hedonic experience of virtual maritime simulator</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Kimmo Tarkkanen</string-name>
          <email>kimmo.tarkkanen@turkuamk.fi</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Juha Saarinen</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Mika Luimula</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Timo Haavisto</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Turku University of Applied Sciences</institution>
          ,
          <addr-line>Joukahaisenkatu 3, Turku</addr-line>
          ,
          <country country="FI">Finland</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2023</year>
      </pub-date>
      <volume>1</volume>
      <fpage>8</fpage>
      <lpage>21</lpage>
      <abstract>
        <p>Virtual training is resource effective and sometimes only option for practicing complex situations in hazardous environment. Maritime training and certificates are regulated by standards yet recently opened for virtual training possibilities. In this paper, we study how maritime students experience a new gamified VR training environment in their common training episodes at sea. We introduce a unique, state-of-the-art system for training maritime scenarios, and 25 students' subjective comparison to their experiences in traditional maritime simulators. They evaluated the efficiency in learning and the pragmatic quality of the new system only slightly below traditional simulators. The hedonic quality was evaluated much higher than of traditional. The new system was considered also more engaging and realistic. In the latter, users seemed to value more the realism of the visual environment than the realism of using the ship controls. Virtual reality, game-based learning, safety training, maritime, user experience be</p>
      </abstract>
      <kwd-group>
        <kwd>learning</kwd>
        <kwd>in</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>Interests in remote and virtual training has
increased rapidly due to recent pandemic, which
prevented face to face
meetings and closed
training centers. Training in virtual environments
is
resource
effective
and
in</p>
      <p>hazardous
only option for practicing
environment the
complex situations.</p>
      <p>
        That is a case in maritime education all over
the world: Simulated scenarios in cave rooms [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]
are the backbone of educating new seafarers, the
people who can navigate and steer large passenger
ships and container vessels safely in any sea.
Simulations are also an important part of life-long
training of more experienced sea captains, who
currently need to land and use their spare time for
additional training.
      </p>
      <p>Maritime training and certificates are regulated
by standards, which purpose is to ensure that the
simulations
provide
appropriate level of
physical and behavioral realism as well as agreed
body of knowledge and assessment objectives.
Maritime industry has recently modified their</p>
      <p>
        2023 Copyright for this paper by its authors. Use permitted under Creative
also
cloud-based,
fully
asynchronous
[
        <xref ref-type="bibr" rid="ref2">2</xref>
        ].
      </p>
      <p>
        This
has
artificial
opened
and
new
opportunities for online virtual training systems in
maritime context. In the search of contemporary
and relevant topics for the field of game-based
learning
[
        <xref ref-type="bibr" rid="ref3">3</xref>
        ],
maritime
safety
and
training
represents one: There are continuous fear of large
environmental catastrophes due to shipwrecks
like the one in Suez Canal [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. Could game-based
learning paradigm improve safety training and
maritime across
continents and
      </p>
      <p>Virtual reality (VR) is considered here as a
technology
that
can
significantly
improve
seafarer’s performance and competence with the
adaptation of maritime applications developed for
design simulation and gaming. For example,
mobility of head-mounted VR equipment allows
training independent of time and place, even when
the ship is sailing at the sea. From safety and
business perspective, this opportunity is more
effective compared to booking a simulator room
at land. However, from the user perspective, it is
unknown how seafarers themselves receive such
VR training possibility.</p>
      <p>In this paper, we study how maritime students
experience a new VR training environment in
their common simulator training episodes. We
introduce a unique, state-of-the-art system for
training maritime scenarios, and students’
subjective comparison to their experiences in
traditional simulators. To our understanding, there
are currently no scientific studies about
headmounted VR-based training simulations in ship
maneuvering and navigation outside our research.
2.</p>
    </sec>
    <sec id="sec-2">
      <title>VR simulation and training system for maritime</title>
      <p>The system is developed for practicing
different collision avoidance situations at seas.
The command bridge, which is implemented as a
digital twin to the virtual environment, contains
common equipment for ship maneuver and
navigation operations such as a radar, ECDIS (i.e.,
map + route plan), auto pilot, manual steering, and
engine power controls. The controls of the bridge
are limited, yet their functionality correspond with
the real bridge of a large vessel.
main difference is that the physical command
bridge with buttons, handles and rags are now
virtual (Figure 2).</p>
      <p>
        The system is used with Varjo VR headset [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]
without separate control devices in player’s hands
(Figure 1). The system exploits eye-tracking
feature [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] and hand gesture recognition [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ],
which allow more natural interactions with the
command bridge. Compared to a traditional
multiscreen simulation setting in a cave-like room, the
      </p>
      <p>The system supports behavioral data collection
and records all the moves of all ships and all
player actions (hand gestures and eye movements
with objects) into the database. This allows
reconstructing player’s path, actions, and the
whole performance, whilst training the dedicated
neural network for further performance analysis.</p>
      <p>In the future, with the help of artificial
intelligence, it is possible to give detailed
(proactive or reactive) information to the player
during or after the play session. For example, the
system could proactively guide and highlight to
the player the required operations based on the
activity patterns it has learned from successful
scenarios. Notable is that the order and timing of
player actions can vary in successful
performances. For debriefing phase, typical to
maritime education, the system could
automatically recognize actions that are risky
(e.g., not following evasive rules, passing
distances) and their relative time compared to
optimal (e.g., time on task, looking at sea vs.
bridge). The development has recognized
possibilities for more gamified elements such as
use of leaderboards and badges.</p>
      <p>
        Transforming a conventional training to a
game-based does not automatically lead to higher
learning or motivation in users [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. Therefore, the
system is designed together with maritime
training experts and experienced seafarers
following user-centered design practices. Expert
involvement aimed at increasing narrative quality
and realism of the system, which could influence
players’ views about learning effectiveness in a
serious game [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. The collision scenarios are
designed by the experienced teachers and
seafarers. Implementations of bridge controls
were also frequently tested by one expert (Fig. 5).
      </p>
      <p>Total of 25 international maritime students
participated in the tests in four days long test
sessions. On average, participants had 93 study
credits and 2 to 4 years studies in higher maritime
education unit in Finland. The average grade of all
their maritime related courses was 3.8/5. They had
previously used conventional maritime simulators
10 times (median), and the last use was no longer
than two weeks before the test session, and for
some participants, even earlier on the same day.
Their previous play experiences with any VR
device varied between 0 and 2 times.</p>
    </sec>
    <sec id="sec-3">
      <title>3.1 Session protocol</title>
      <p>In the game play, the player was steering a
large, 200-meter long, tanker ship (Figure 6).
Before taking the ship into their control,
participants went through a tutorial, which
introduced the main controls and types of
interactions (due to difference to reality).</p>
      <p>
        Participants played two maritime scenarios,
first an easy and then a difficult scenario, which
varied in length (15 and 30 minutes
correspondingly). Both scenarios required skills
of basic navigation and collision avoidance that
based on the participants’ background they
possessed. The difficult scenario consisted of
more ships on the sea heading or colliding with
the player’s ship than the easy scenario. Thus,
more cognitive load and challenge was expected
in the difficult scenario, that in turn was expected
to lead to improved learning outcomes [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ].
      </p>
      <p>There were no specific tasks given to
participants. In the beginning of each scenario, the
system showed the target location, required
arrival time and weather conditions i.e., common
information for all similar maritime simulations.
The total number of played scenarios were 40 due
to 2 participants quitting after the easy scenario
and 8 participants playing only the difficult
scenario.</p>
    </sec>
    <sec id="sec-4">
      <title>3.2 Data collection</title>
      <p>
        Behavioral data about eye movements and
player actions were collected automatically to a
database, that was used for training a neural
network. For the experience data analyzed in this
paper, we used two validated questionnaires UEQ
and SUS. As the enjoyment and realism have a
significant impact on subjective learning
effectiveness in serious games [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ], we asked
participants’ opinion about these, as well as
collected their basic demographic data.
      </p>
      <p>
        Total number of 40 different answers to the
short version of User Experience Questionnaire
(UEQ) [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. Short UEQ was answered
immediately after the scenario was played. The
short UEQ questionnaire evaluates both
pragmatic and hedonic quality of the system with
8 different items containing negative and positive
extremes (Figure 7). The pragmatic quality scale
is like the usability concept in goal-oriented
activity, while hedonic quality scale emphasizes
user’s attraction to technology and its novelty
value. Interpretation and analysis of UEQ results
followed the original [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. After the UEQ,
participants answered two questions: How easy
the scenario was, and how do they grade their own
performance in it (scale 1-5 with an open answer).
      </p>
      <p>
        The SUS questionnaire, which was turned to
positive [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] due to supposed cognitive load [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ],
was answered by 17 participants and only once in
the end of the test. The SUS was targeted for the
overall system evaluation, not to any specific
scenario played.
      </p>
      <p>After the SUS, participants were asked if the
VR system was 1) more efficient for their learning
2) more realistic and 3) more engaging than other
simulators they have used before. These were
assessed on scale 1-5, where 1 = strongly
disagree... 3= neutral .... 5 = strongly agree. Then
became open questions about their feelings and
thoughts as well as wishes to the developers. The
last question was to assess their previously used
simulator with same 8 items of Short UEQ and
write the date when last used (for this and other
background data, see the beginning of the
chapter).
4.</p>
    </sec>
    <sec id="sec-5">
      <title>Results</title>
      <p>The new VR system was evaluated slightly
more realistic (3.64/5) and engaging (3.44/5) than
other simulators the participants have used before
(researcher’s own questions 2 and 3 in the
previous chapter). This result is in line with the
results of UEQ questions. The hedonic quality
scored 1.819, which is much higher than with
traditional simulators (1.015) in scale – 3 - + 3. On
the other hand, the new VR system is not
considered more efficient for learning the
maritime practices than other simulators the
participants have used (researcher’s question 1).
The average of 25 answers was 2.92/5, which is
slightly below the middle. In UEQ, traditional
simulators score also slightly higher in pragmatic
quality (1.265) than the new system (1.225).
Overall experience score for the new system is
higher (1.519) than traditional simulators (1.063).</p>
      <p>
        When interpreting the results and
benchmarking values to other applications
according to historical UEQ data [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ], the VR
system scores above average on pragmatic quality
(i.e., 50% of applications result worse).
Correspondingly, the score of the new system
means that the system is good on hedonic quality
(i.e., only 10% of applications result better, and
75% result worse). The overall score denotes good
as well (Figure 8).
      </p>
      <p>Maritime VR</p>
      <p>SUS score for the VR system is 66. The score
is interpreted as Ok/Good, yet slightly below the
average, as the SUS score 68 is the average of all
applications. That is in line with the mean of
pragmatic quality in UEQ results that SUS mainly
measures.</p>
      <p>The participants agreed (on avg 3.8/5) that the
difficult scenario was indeed more complicated
than the easy scenario2. Comparing Short UEQ
scales between the two scenarios, the difficult
scenario was assessed better in both pragmatic
(1.132 vs. 1.228) and hedonic quality (1.765 vs.
1.924). Self-assessed performance shows slight
improvement (learning) from easy to difficult
scenario as the average (school) grade given
raised from 4 to 4.38 on average.</p>
    </sec>
    <sec id="sec-6">
      <title>Discussion</title>
      <p>Delightfully, participants evaluate the new VR
system high in hedonic quality and more realistic
and engaging than the traditional systems they
have previously used. Considering realism of VR,
users seem to value environmental realism more
than realism in their own interactions. All
equipment in traditional simulators, radars, tillers,
and other tools used with their hands are
physically and truly real, while the horizontally
viewed environment (sea, weather, vessels, and
their subsequent behavior after the interaction) is
digitally produced on multiple screens i.e., virtual.
In the new VR system, the quality of the
environment is much higher: user’s field of vision
is more solid and integrated, objects in the horizon
2 Forthcoming analysis of eye-tracking data [14] shows also
increased cognitive load as less targeted and uncertain gaze paths
[15].
are visually sharper, sea and ship physics are
improved etc. In turn, equipment and interactions
are probably the most unrealistic part of the VR
system. Although close to a digital twin, the
command bridge contains relatively new
interaction gestures (grabbing), low number of
features (ECDIS and radar had only the main
functions) and incompleteness of visual content of
controls (e.g., missing map elements). In addition,
users had to change their normal behavior due to
missing hand recognition when out of vision. For
example, many times users tried to turn the ship
using the tiller while looking at their effects and
estimating the correct turning position in the
horizon. However, this natural maneuvering
action in VR requires splitting it into several
smaller operations where tiller use and looking to
the sea need to alternate. Another pragmatic
problem observed was the discomfort of wearing
the VR headset for long time [16]: to our
experience, two scenarios on a row (15+30 mins)
was too much. Clearly, these inconsistencies and
problems in the command bridge and related
controlling tasks of the ship are reflected in
pragmatic quality evaluations of SUS and UEQ
questions. Luckily, such inconveniences should
not affect negatively to users’ intention to use and
immersion [17].</p>
      <p>On the other hand, pragmatic quality was
evaluated almost as good as in users’ traditional
simulators, which gives an indication that
completely new interfaces and interactions can be
implemented and accepted by users in a virtual
setting. While both, XR technology and remote
and autonomous ships, are developing rapidly, we
need more research on appropriate types of user
interactions, interfaces, and gestures that allow
one user to control even multiple vessels
simultaneously. Practicing these tasks in a serious
game-like environment is an advantage.</p>
      <p>
        Although subjective effectiveness of the
system was evaluated adequate, we acknowledge
that our study design lacks scientific rigor in
evaluating the effectiveness of the system and
comparing it to traditional systems. For example,
our participants were experienced users of
traditional simulators and had used these recently,
however our intervention lacks these simulators
for more rigor comparison. Therefore, this study
should be seen as a feasibility study [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]
investigating only the feasibility of implementing
digital game-based learning in maritime safety
context and of reaching pragmatic and hedonic
goals set to the system. Moreover, the applied
short UEQ, and especially its hedonic quality
scale, seems to fit well this type of innovative
systems and unique experiences causing possibly
biased results. VR gaming in general is driven by
hedonic values [17] and a part of players’ hedonic
valuing may be a result of their very first
experiences with VR systems.
      </p>
      <p>The development of the system and especially
training of neural network is going on. The system
is already trained with synthetic ship-movement
data (270 computer run training sessions and 100
validating sessions) achieving over 90% accuracy
in separating passing and failing performances
based on paths and distances between ships.</p>
      <p>Since the user tests reported here, the VR
system has been developed for multiplayer
environment in a metaverse and played by 58
maritime students in Philippines and 43
wellexperienced maritime students in Sweden. These
data are used for training the neural network to
become a standalone and a trusted party in
accepting or rejecting training certificates in
maritime context.</p>
    </sec>
    <sec id="sec-7">
      <title>6. Acknowledgments</title>
      <p>We acknowledge the maritime students and
experts, and the personnel at Turku Game Lab,
who have participated in designing,
implementing, and testing this system. This
research has been supported by the Business
Finland funded project called “Maritime
Immersive Safe Oceans Technology (MarISOT)”.</p>
    </sec>
    <sec id="sec-8">
      <title>7. References</title>
      <p>[14] C.-M. Calbureanu-Popescu, Eye-movement
metrics of cognitive load in naval command
bridge setting, Master's thesis, University of
Turku (Forthcoming).
[15] R. Dewhurst, T. Foulsham, H. Jarodzka, R.</p>
      <p>Johansson, K. Holmqvist, M. Nyström, How
task demands influence scanpath similarity
in a sequential number-search task. Vision
Research, 149, 9–23, (2018).
[16] S. A. Penumudi V. A. Kuppam, J. H. Kim, J.</p>
      <p>Hwang, The effects of target location on
musculoskeletal load, task performance, and
subjective discomfort during virtual reality
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[17] T. Kari, M. Kosa, Acceptance and use of
virtual reality games: an extension of
HMSAM. Virtual Reality, (2023).</p>
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