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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>February</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>Field Lab Sleep and Energy: A System for Longitudinal Remote Sleep Tracking and Prototyping</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Peter Lovei</string-name>
          <email>peter.lovei@philips.com</email>
          <email>peter.lovei@philips.com eva.deckers@philips.com Philips Experience Design Eindhoven, The Netherlands</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Mathias Funk</string-name>
          <email>m.funk@tue.nl</email>
          <email>m.funk@tue.nl s.a.g.wensveen@tue.nl Industrial Design, Eindhoven University of Technology Eindhoven, The Netherlands</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Eva Deckers</institution>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Stephan Wensveen</institution>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2021</year>
      </pub-date>
      <volume>17</volume>
      <issue>2021</issue>
      <abstract>
        <p>CCS CONCEPTS</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>There is both clinical and consumer interest in remote sleep
tracking technologies. Sleep is interesting to be observed remotely, in
a (smart) home environment. For longitudinal design research we
needed to collect data for a longer period of time. Therefore,
using the Data-Enabled Design process we built Field Lab Sleep and
Energy. We conducted a user study for a period of one year using
this system. Using the system the team could gather, store, process,
visualize and analyze the incoming behavioral, experiential and
contextual data. We built and embedded a communication
platform in the system aiming to prototype human-IoT experiences.
The RelaxBreathe program was one of these prototyped and tested
human-IoT experiences. This positioning paper introduces Field
Lab Sleep and Energy, the RelaxBreathe program case study and
the findings of the team.</p>
      <p>Copyright 2021 for this paper by its authors. Use permitted under Creative Commons
License Attribution 4.0 International (CC BY 4.0).
• Human-centered computing → Systems and tools for
interaction design; User studies.
data-enabled design, longitudinal design research, human-IoT
experiences, prototyping, designing for sleep
1</p>
    </sec>
    <sec id="sec-2">
      <title>INTRODUCTION</title>
      <p>There is both clinical and consumer interest in remote sleep
tracking using wearable technologies [10]. Sleep is complex and both
objective and subjective, Sleep is personal and context dependent.
Sleep varies over time. As such it is a suitable topic to be explored
by remotely tracking it at people’s homes. Liang et al.’s [7] paper
describes SleepExplorer a visualization tool for personal sleep data
and contextual factors. Their sleep study was conducted for two
weeks in length. The authors emphasize the opportunity for being
able to provide tailored instructions and recommendations for
behavior change. In order to do so a longer period of data collection
is necessary.</p>
      <p>By applying the Data-enabled Design (DED) process [13] it is
possible to design prototypes for intelligent ecosystems. Using these
prototypes a multidisciplinary design (research) team collects
objective and subjective data [8]. The built systems consist of (IoT)
products, services and people. The team is actively involved in
setting up, conducting, analyzing and communicating the results
of these studies. Studies in the past were conducted for a short to
medium period of time (1-4 months). However, it is not always
possible to learn enough about a certain domain, or about the
everyday use of the designed intelligent ecosystem without deploying
it in the field for a longer period of time. Therefore, we decided to
explore how to conduct longitudinal design research for a period
of a full year focusing on the topic of remote sleep tracking using
IoT technologies. We built the Field Lab Sleep and Energy system.
In this positioning paper we are presenting a case study about how
to prototype Human-IoT experiences using Field Lab Sleep and
Energy.
2</p>
    </sec>
    <sec id="sec-3">
      <title>FIELD LAB SLEEP AND ENERGY</title>
      <p>Field Lab Sleep and Energy is an intelligent ecosystem designed
for conducting longitudinal design research, exploring the topic of
remote sleep tracking using IoT technologies deployed in people’s
home environment. By applying the DED process [13] the design
research team has made the following decisions for the design of
the system. Field Lab Sleep and Energy consists of of-the shelf
IoT devices that collect contextual, behavioral and experiential
data related to remote sleep tracking and can be used in the home
environment of its users. The built system is made to function for
a duration of a full year.</p>
      <p>
        Using the system the team wanted to be able to prototype
humanIoT experiences based on the data collected via the remote sleep
tracking activities. Therefore, we developed a way to be able to
gather, store, process, visualize and analyze the incoming data.
Moreover, by building and embedding a communication platform
in the Field Lab Sleep and Energy system the design research team
could (
        <xref ref-type="bibr" rid="ref1">1</xref>
        ) instruct participants, (
        <xref ref-type="bibr" rid="ref2">2</xref>
        ) modify the functionality of the
design probes, and (
        <xref ref-type="bibr" rid="ref3">3</xref>
        ) gather feedback about how the participants
are experiencing the ecosystem they’re using.
2.1
      </p>
    </sec>
    <sec id="sec-4">
      <title>Conducted User Study</title>
      <p>
        From December 2018 till December 2019 we conducted the Field
Lab Sleep and Energy study. We deployed the Field Lab system in
the homes of five participating families from the Eindhoven region
of The Netherlands. The five participating couples were selected to
be (
        <xref ref-type="bibr" rid="ref1">1</xref>
        ) healthy individuals with no (diagnosed) sleep disorder, and (
        <xref ref-type="bibr" rid="ref2">2</xref>
        )
tech savvy consumers. During the study we collected 2979 nights of
Withings data, 876 days of subjective sleep data, 109076 data points
about their bedroom environment, the participants opened the app
4500 times, and 10350 Chat messages were exchanged via the built
communication platform. The study was positively approved to be
conducted by the Internal Committee for Biomedical Experiments
(ICBE) of Philips.
      </p>
    </sec>
    <sec id="sec-5">
      <title>Remote data collection via the Field Lab system</title>
      <p>
        Using the Field Lab system we can collect behavioral, experiential
and contextual data. It is achieved by the deployment of the
following design probes at participating families’ homes: (
        <xref ref-type="bibr" rid="ref1">1</xref>
        ) Withings
Sleep Analyzer [15], (
        <xref ref-type="bibr" rid="ref2">2</xref>
        ) a Somneo Wakeup Light [9], and (
        <xref ref-type="bibr" rid="ref3">3</xref>
        ) the
Field Lab Sleep iOS application.
2.2.1 Withings Sleep analyzer. The Withings Sleep Analyzer is a
WiFi-enabled IoT device that is placed under the mattress in the
bed. The device collects data about its users’ sleep and sends the
collected data over WiFi to the Withings cloud. The Field Lab Sleep
and Energy system is able to retrieve the collected, and analyzed
sleep data from the Withings cloud via their oficial API [14].
      </p>
      <p>Data collected by Withings Sleep Analyzer that is used by Field
Lab:
• Time participant spends in bed (duration)
• Total sleep time (duration)
• Time awake (duration)
• Sleep eficiency (percentage: time asleep / total duration in
bed)
• Sleep onset (timestamp)
• Sleep ofset (timestamp)
2.2.2 Somneo Wakeup Light. The Somneo Wakeup Light is a
WiFienabled IoT device that uses light and sound to wake its users up.
It is possible to setup the alarm time and customize its sound via
the display of the light or via a smartphone application. There is
a relaxed breathing feature (RelaxBreathe) ofered by the light as
well. This feature can be triggered manually via the display of the
light. The light contains sensors that collect data about the bedroom
environment of the user.</p>
      <p>Data collected by Somneo Wakeup Light that is used by Field
Lab:
• Temperature (degrees)
• Humidity (percentage)
• Sound level (decibel)
• Light level (lux)
• Time RelaxBreathe feature was started (timestamps)
• Time RelaxBreathe feature was ended (timestamps)
• Alarm usage (timestamps)
2.2.3 Field Lab Sleep mobile application. The Field Lab Sleep
mobile application was custom-developed for Field Lab. It was
developed using React Native [11] for iOS devices. First of all we
built a Chatbot to keep participants engaged during the study, ask
questions for gathering feedback, and for being able to remotely
instruct participants on how to use the devices. Secondly, we built
a Newsfeed to provide content to keep participants engaged, and
educate them about their sleep. Finally, we developed a way for
participants to look at visualized data reports and feedback. The
participants are encouraged to use the app on a daily basis and are
notified every time there is a new chat message, Newsfeed content
or personalized report sent to them.</p>
      <p>
        Data collected by the Field Lab Sleep mobile application that is
used by Field Lab:
• App usage data (opening, closing timestamps, duration spent
on screens)
• Sleep related questions and answers: Sleep quality,
Restfulness/Refreshed, Alertness, Consensus Sleep Diary [2]
• Qualitative questions and answers (scale from 1-10)
Using the Field Lab system the team was able to create prototypes
to (remotely) test Human-IoT experiences. This is achieved by
using the following two components: (
        <xref ref-type="bibr" rid="ref1">1</xref>
        ) the back ofice and (
        <xref ref-type="bibr" rid="ref2">2</xref>
        ) the
communication platform. During the study we used the system to
modify the capabilities of the IoT components, tracked the usage of
system components, instructed participants to use the devices
differently, and gathered feedback about the experience of participants
using the system via the mobile application.
2.3.1 The back ofice of the Field Lab Sleep and Energy system. In
order to be able to analyze the incoming experiential, behavioral
and contextual data we built a back ofice that could be centrally
accessed by all the members of the (design) research team. The back
ofice was deployed on AWS and data is stored in MongoDB. The
main functionalities of the back ofice are the following: (
        <xref ref-type="bibr" rid="ref1">1</xref>
        ) present
data visualisations to the researchers based on the collected data,
(
        <xref ref-type="bibr" rid="ref2">2</xref>
        ) enable the researchers to play with the incoming data and the
data visualizations.
2.3.2 The communication platform of the Field Lab system. Using
the communication platform of the Field Lab Sleep and Energy
system the (design) research team can (
        <xref ref-type="bibr" rid="ref1">1</xref>
        ) schedule pre-written
chat bot messages, and news feed articles, (
        <xref ref-type="bibr" rid="ref2">2</xref>
        ) compose reports
about the participants data that can be shown in the Field Lab Sleep
mobile application. The chat bot messages are pre-written in the
Flow.AI [3] platform that is used to define the logic of the chat
bot. The back ofice of the Field Lab communicates with Flow.AI
via their WebSocket API [4]. The news feed articles are stored in
a MongoDB database. The researchers need to define their title,
subtitle, and a URL that points to the content to be shown to the
participants. The reports about the participants’ data are special
kind of news feed articles that contain a link to a PDF document
that is stored in an AWS S3 bucket.
3
      </p>
    </sec>
    <sec id="sec-6">
      <title>CASE STUDY: RELAXBREATHE PROGRAM</title>
      <p>The Field Lab Sleep and Energy system was created in order to
prototype Human-IoT experiences. Based on the collected data
from the Withings Sleep Analyzer and the answers given to the
sleep related questions asked via the communication platform we
noticed that 5 of the 10 participants had troubles falling at least
twice a week. Therefore we decided to introduce the RelaxBreathe
program, a personalized, visually-guided breathing program that
can prevent stress to accumulate during the day, in order to facilitate
sleep initiation and continuation at night.</p>
      <p>In order to prototype this experience the team has used the back
ofice, the communication platform and the Somneo Wakeup Light.
We developed a custom solution that uses a Raspberry Pi [6] with
Node-RED [5] installed on it to connect to the Somneo Wakeup light
via the local WiFi network. This way it is possible to read out sensor
data from the light and control the Relax Breathe feature. It was
achieved by sending AWS IoT [1] messages to the Raspberry Pi that
triggers the commands on the Somneo by first finding the device
on the local WiFi based on its’ Mac address and then forwarding an
HTTP POST command to the device over the local WiFi network.
The device itself is able to interpret the incoming message and
trigger the RelaxBreathe feature as if the participant pressed the
respective button on its display.</p>
      <p>
        Using the communication platform we sent chat messages to
each participant of the study that they could read inside the Field
Lab Sleep mobile application. By reading the messages they were
introduced to the program, and we asked whether they were
interested in joining it. If they decided they wanted to participate they
were guided to setup their schedule. Depending on their schedule
they received a Chat-based prompt together with a push
notification to start the breathing exercises on their Somneo Wakeup Light.
Each participant could decide to (
        <xref ref-type="bibr" rid="ref1">1</xref>
        ) use the light for the breathing
exercises, (
        <xref ref-type="bibr" rid="ref2">2</xref>
        ) delay the exercise for a later moment, or (
        <xref ref-type="bibr" rid="ref3">3</xref>
        ) to skip the
exercise. After they have finished with their exercise they got an
encouraging message from the system. If the participants decided
to do the breathing exercise the Flow.ai was programmed to ask the
back ofice to send a message to the Raspberry Pi via the AWS IoT
service to start the exercise over the local WiFi network to which
the Somneo light was connected.
      </p>
      <p>
        Next to the exercises we sent tips and news feed articles related
to the benefits of the relaxation before going to bed. After 7 days
the participants received a personal report that included a data
visual and had the opportunity to reflect on the program. They
could decide to (
        <xref ref-type="bibr" rid="ref1">1</xref>
        ) continue as before, (
        <xref ref-type="bibr" rid="ref2">2</xref>
        ) adopt their schedule, (
        <xref ref-type="bibr" rid="ref3">3</xref>
        )
or leave the program.
      </p>
    </sec>
    <sec id="sec-7">
      <title>3.1 Results</title>
      <p>Two of the 10 participants have decided to continue the program
even though we have told them via the Chat messages that the
program was over. They reported that the program helps them falling
asleep better and helps them relaxing. We have also received
feedback on how to improve this experience by further personalizing
the program to the user’s context. For one of the participants using
the light felt like a task instead of relaxation as this person did not
have problems with falling asleep. Other users have reported to
make the time of the exercise more easily customizable, as many
times it happened that the exact moment they received the Chat
prompt they were doing something else and then forgot about it.
Moreover, the participants have also provided feedback for how to
improve the IoT aspect of the program as they have asked us to
introduce diferent channels or devices for delivering the exercise.
One participant would have preferred voice based guidance instead
of the light based one provided by our team. Last but not least, our
program has also shown the importance of improving the Field Lab
Sleep and Energy system to gather data about people’s motivation
when testing out human-IoT experiences. Based on the suggestions
of the users the program could be improved by further improving
the connection to all the experiential, contextual, and behavioral
data that was collected from their homes.</p>
    </sec>
    <sec id="sec-8">
      <title>4 CONCLUSION AND FUTURE WORK</title>
      <p>In this position paper we presented Field Lab Sleep and Energy.
The system was designed for longitudinal design research into
remote sleep tracking. The introduced system was used in a design
research study for the duration of one year. We selected the IoT
components that were deployed in people’s homes in a way that
based on the gathered, and analyzed remote sleep tracking data the
team could come up and prototype new human-IoT experiences. By
developing and embedding a communication platform the design
research team was able to instruct participants to use the devices
diferently, track their device usage and gather their feedback about
the new way of using the IoT device. This way we could prototype
a new human-IoT experience.</p>
      <p>The presented case study shows how to remotely setup a
relaxation before sleep experience. The case study was successful
for setting up and executing the program, and gathering feedback
from the participants. Some participants have appreciated using it
while others have provided valuable feedback to further improve
the experience and the Field Lab Sleep and Energy system.</p>
      <p>During the one year the system was used for prototyping other
experiences around the topic of family sleep [12], bedroom
environment and sleep regularity. In all cases we used the same method of
instructing participants, potentially modifying the technical setup,
tracking the usage interactions and gathering feedback using the
system. In the future we aim to explore other health technology
topics using similar ecosystems that are designed by applying the
DED process.</p>
    </sec>
    <sec id="sec-9">
      <title>ACKNOWLEDGMENTS</title>
      <p>The authors would like to thank Anne Wil Burghoorn, Melanie
Meyfroyt, Erwin Hoogerwoord, Thomas Visser and the rest of the
colleagues working on this project. We also would like to thank the
participants of the Field Lab Sleep and Energy study.</p>
    </sec>
  </body>
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