synthetic skin-like sensing in wearable garments · objects, whether made of cloth or not. velostat...
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Synthetic Skin-like Sensing in Wearable Garments
July 16, 2016
New Jersey Governor’s School of Engineering and Technology
Abstract
The field of electronic textiles (e-
textiles) possesses a variety of applications;
one inexpensive and practical application
lies in creating unobtrusive pressure sensors.
The e-textile pressure sensor is created with
a circuit of conductive thread, the voltage
and resistance of which is inversely
proportional to the pressure applied on the
sensor. E-textiles may be used both for
recreation and for monitoring the health and
wellbeing of their users. In this research
project, the pressure sensors were attached
to an Arduino and integrated first into the
fingertips of a glove, for recreational
purposes, then into a pillowcase, for
purposes of tracking a user’s sleep cycles
throughout the night. Future work may
apply these e-textile pillows in an effort to
diagnose certain sleeping disorders
characterized by atypical movement while
asleep.
1 Introduction
1.1 Introduction to E-Textiles
The term “e-textiles” refers to
materials such as fabric, yarn, or thread that
incorporate conductive properties and
electronic elements without the discomfort
or bulkiness of traditional wires and
electronic devices [1]. E-textile research and
development focuses on a variety of areas;
practical uses of e-textiles extend from
monitoring health to altering aesthetics,
from heating and cooling to tracking
location [2].
1.2 Importance of Sleep
Many studies have demonstrated the
value of sleep. At the very least, it prevents
drowsiness during the day, improves
learning, and sustains physical health [3].
Despite growing research that reveals just
how critical sleep is, however, many people
never seem to sleep enough. According to
the Centers for Disease Control and
Prevention (CDC), anywhere from 50 to 70
million Americans suffer from sleep or
wakefulness disorders [4].
Fortunately, as sleep awareness
becomes more prevalent in developed
countries, many people hope to better
understand their own body. Because sleep is
divided into different stages of
consciousness, activity, and movement,
tracking sleep becomes a matter of
interpreting the relevant data points.
Claire Furino
Anna Qin
Rebecca Granovskiy
Bret Silverstein
Madeline Wong
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2 Background of E-Textiles
and Sleep
2.1 Importance of E-Textiles
E-textiles are a valuable field of
research because of their diverse
applications and unobtrusiveness. For
example, current consumer heart-rate
monitors are watch-like bands worn around
the wrist; however, e-textiles could integrate
these monitors into everyday clothing of
normal thickness and feel. Rather than
relying on intermittent doctors’
appointments to measure personal health
data such as blood pressure or heartbeat, one
may instead monitor these vitals on a regular
basis [5].
In addition to these health
applications, e-textiles also have
applications in military use. International
Fashion Machines has developed color-
changing e-textiles that could eventually
become the material of military uniforms,
introducing a novel version of the ubiquitous
army “camouflage” [6]. These e-textiles
could also monitor vitals and precisely
locate a soldier’s wounds for rapid treatment
on the battlefield [6].
In the consumer fashion industry,
companies have introduced clothing that can
heat or cool based on one’s temperature or
preference [6]. In particular, athletic
clothing companies such as NuMetrex have
already integrated e-textiles in clothing to
record vitals during exercise, while other
companies hope to use e-textiles to measure
muscular strain [2, 7]. In this project, the
focus lies in the use of e-textile pressure
sensors in pillows for monitoring sleep.
2.2 The Sleep Cycle
The sleep cycle is typically divided
into four stages: stages one, two, and three,
and rapid eye movement sleep (REM).
During sleep, one continually cycles through
these four stages until awaking.
In the first stage of sleep, one drifts
in and out of slumber, and may easily be
awakened. Stage one typically lasts from
five to ten minutes [8]. Stage two, while a
deeper sleep than stage one, is still
considered very light. Stage two lasts
approximately 10 to 25 minutes, during
which body temperature and heart-rate fall
[8, 9]. As sleep deepens and breathing
becomes more regular, the body prepares for
deep sleep [8].
Stage three is considered deep sleep:
this is where the body begins to repair,
strengthen, and restore [8]. Stage three lasts
20 to 40 minutes [9].
The last stage of sleep before the
cycle restarts is REM sleep. The first period
of REM occurs between an hour and an hour
and a half after first falling asleep; when the
cycle is repeated, these periods become
progressively longer as stage three becomes
progressively shorter [10]. While the first
period of REM lasts only 10 minutes, the
final REM stage may last as long as an hour
[8]. During this stage of sleep, limbs become
paralyzed and breathing becomes shallow
and irregular [10].
2.3 Ohm’s Law
According to Ohm’s Law, voltage is
the product of current and resistance (see
Equation (1)). Therefore, voltage is directly
proportional to resistance when current is
held constant.
V = iR (1)
2.4 Materials and Tools
The e-textiles synthesized over the
course of this project are made with cotton
fabric, conductive thread, and Velostat.
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The silver-coated nylon conductive
thread may be used to create circuits, yet its
pliability and softness closely mirror those
of normal natural fiber thread. Therefore,
conductive thread allows for less intrusive
technology to be incorporated into various
objects, whether made of cloth or not.
Velostat is a conductive material
whose resistance decreases when it is
compressed or bent [11]. It is a flexible and
thin sheet of material that may, with no
discomfort to users, be slipped between two
layers of normal cloth fabric and be used for
various conductive sensors. If constant
current flows through Velostat, then
pressure applied to the Velostat can be
measured based on the change in voltage of
the circuit.
2.5 Using Sensors to Record Sleep
To monitor the sleep cycle of an
individual, e-textile pressure sensors in a
pillow can record the amount and location of
pressure on the pillow throughout the night.
Movement would be characterized by
fluctuations in this data, suggesting the
stages of sleep a user would experience
throughout the night. In REM sleep, a
typical user would demonstrate temporary
paralysis, leading to an extended period of
no changes in the pressure data. On the other
hand, movement during other stages would
result in changes to the pressure data.
2.6 Importance of Sleep Monitoring
While tracking sleep is of particular
importance for those with sleeping disorders
or trouble sleeping, the benefits of sleep
monitoring extend also to the public as a
whole. Tracking one’s sleep can produce
tangible ways of ameliorating the negative
impacts of poor or little sleep. For example,
sleep cycle data, once analyzed, can be used
to set alarms meant to wake the user up
during a period of light sleep; it can also be
used to suggest bedtimes for users based on
analysis of many sets of sleep data. If sound
sensors are later incorporated into pillows as
noninvasively as the e-textile pressure
sensors, then users can also track sounds and
movement in conjunction to determine how
ambient noise affects the wellness of their
sleep.
In addition to the general benefits of
sleep monitoring, it may also be used to
identify sleeping difficulties or disorders in
order to treat problems that would otherwise
escape unnoticed. One sleeping disorder,
REM Sleep Behavior Disorder (RBD), can
possibly be diagnosed early in its onset with
the use of pressure sensors to monitor
movement. People who suffer from RBD do
not become temporarily paralyzed while in
REM; thus, they act out their dreams by
doing anything from speaking to
sleepwalking. The most extreme symptoms
may lead to injury or danger, as one may
accidentally hit someone or harm oneself
while acting out one’s dream [12].
Nonetheless, some of those inflicted with
RBD do not fully act out their dreams until
years after the disorder’s onset, instead only
twitching or talking in their sleep [12].
Therefore, sleep trackers can detect these
slight movements before they escalate into
dangerous sleepwalking.
2.7 Market for E-Textile Pillows
As the consumer market for sleep
monitoring devices grows, more means have
become available: Fitbits, smartphone apps,
and various other devices worn on the body
or placed on the bed. Save the inexpensive
smartphone apps, however, these methods
tend to be costly, ranging from 70 dollars to
200 dollars [13]; in addition, all of these
devices may be unreliable, cumbersome, or
both.
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The least expensive option available
for tracking sleep is through the
accelerometer of a user’s smartphone. When
the smartphone is placed on a bed or
attached to a person, the sleep tracking app
reads and records changes in the phone’s
accelerometer as body movement.
Analyzing these movements, the app
guesses the lengths of each stage of sleep
and how deep the user’s sleep was.
An e-textile pillow finds the middle
ground between the accurate measurements
of wearable sleep tracking devices and the
inexpensive nature of a smartphone sleep
tracking app. It is affordable and accurate,
posing no discomfort to the user due to its
unobtrusive integrated sensors.
3 Designing the Sensors and
E-Textile Products
3.1 Summary of Design and Creation
Process
The first product, a glove, used small
pressure sensors on the glove’s fingertips for
recreational purposes. This glove was made
to test the capabilities of pressure sensors
when connected to an Arduino Uno and to
gain familiarity with applying e-textiles to
achieve a specific goal. The next step
focused on enlarging these sensors and
expanding their potential so that they could
also determine location of applied pressure.
The sensors design was changed from a
small hourglass to a two-dimensional grid of
separate sensors. After the development of
several prototypes, the final design of the
sensor was sewn into a pillowcase and tested
for accuracy in detecting changes in pressure
as well as the location of the pressure.
The sensors were sewn both by hand
and with a sewing machine. The
embroidered conductive thread patterns
were created using computer-aided design
(CAD) software and converted into a
compatible file for the sewing machine to
read.
3.2 Glove Pressure Sensors
It was first necessary to create
working pressure sensors that could be
integrated into a variety of different
products. The initial pressure sensor
prototype was comprised of two small
pieces of cotton cloth, each about one inch
in length and width, and a similarly sized
piece of Velostat, a carbon-impregnated
polyolefin. A small line of conductive thread
was embroidered on each piece of fabric
(see Figure 1).
Figure 1 The diagram above depicts the layout of the first pressure
sensor used in the glove.
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The Velostat is sewn between the
two pieces of fabric on which the conductive
thread is embroidered, such that a circuit is
formed of the thread and the Velostat.
Because of the properties of Velostat, the
resistance in the circuit drops when pressure
is applied. This drop was measured with an
ohmmeter for testing purposes; however,
because there was such a small area of
contact in this design, the pressure sensor
was not sufficiently sensitive or reliable.
The second prototype of the pressure
sensor was similar in design to the first
prototype, except that the conductive thread
was embroidered in an hourglass pattern
rather than a single straight line (see Figure
2). Because this prototype’s thread design
covered more surface area on the sensor, it
was much more accurate in detecting
changes in resistance in the circuit when
pressure was applied. When the sensor was
connected to an Arduino analog input pin,
the voltage in the circuit could be monitored
and changes could be used to trigger a
reaction or be recorded as data.
In the prototypes created in the lab,
the pressure sensors were attached to the
Arduino by connecting the ends of the
conductive thread to wires. However, in
actual clothing or other consumer products,
these wires would be eliminated by
extending the ends of the conductive thread
down the length of the e-textile. The
introduction of microtechnology and
wireless connections to devices used for
recording, receiving, or storing data may
also improve e-textile technology.
3.3 Glove Testing and Capabilities
To test the capabilities of the
hourglass pressure sensors, they were
integrated into the fingers of a glove; one
sensor was sewn onto each fingertip. The
Arduino interfaced with a laptop using
Processing to play a different percussion
sound in response to a change in voltage for
each of the five sensors.
The circuit was powered with a
constant current from the Arduino, making
change in resistance directly proportional to
change in voltage. Since each sensor was
individually manufactured, the threshold
voltage that determined whether the
percussion sound would be produced was
written as a fraction of the initial voltage
without pressure (testing showed that two-
thirds gave consistent results). The Arduino
measured each sensor’s voltage. If it
dropped below the threshold, then that
indicated that pressure was being applied to
Figure 2 The hourglass pattern of the final glove pressure sensors
increases the surface area of the design and the points of contact between
the layers of fabric, making the sensor more reliable.
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the sensor and the corresponding percussion
sound was triggered.
The working prototype of the glove
allows users to “play” a drum-set using their
fingertips, yet without any cumbersome
buttons on the garment—the sensor is
simply a few extra layers of cloth. If this
glove were to be mass-produced, then the
large Arduino would be replaced with
microtechnology, such as the LilyPad
Arduino, and small speakers. Essentially, the
wires connecting to the Arduino would be
replaced by a circuit made completely of
conductive thread.
While the pressure-sensitive “drum
glove” affirms the functionality of the
pressure sensors, it remains a device meant
for entertainment and leisure. E-textiles,
however, have the potential to provide
innumerable noninvasive technologies for
monitoring and aiding in everyday life.
Utilizing the pressure sensors, the next part
of the project focused on creating larger
sensors with the ability to detect the location
of pressure.
3.4 First Pillow Pressure Sensor
Prototype
The pillow’s pressure sensors are
similar in physical design and practical
application to those of the glove: both use a
layer of Velostat sewn between two layers
of fabric embroidered with conductive
thread, and both measure the change in
voltage of current flowing through the
sensor to find pressure. However, since the
pillow sensor is larger and is able to sense
location, it employs a different conductive
thread pattern. Rather than being
embroidered in an hourglass pattern, the
conductive thread runs along the cloth in
equally spaced parallel lines meant to create
circuits with the Velostat and second piece
of embroidered cloth. The threads in one
fabric layer run orthogonal to those in the
other fabric layer. Thus, an X-Y coordinate
grid is formed, essentially making each
point a separate sensor and allowing for the
location of pressure to be determined.
The first implemented pressure
sensor utilizes a conductive thread pattern of
parallel lines. The lines of conductive thread
that run parallel to the X-axis are each
connected to a switch circuit, which is
Figure 3 The final pillow pressure sensor used zigzag lines to increase the
points of intersection of each sensor.
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activated by a ping of current through one of
the digital pins of the Arduino. The pings
are sent successively through each digital
pin to activate individual lines along the X-
axis and prevent overlapping of circuits for
differentiation between locations of applied
pressure. The conductive threads running
parallel to the Y-axis on the second piece of
fabric are connected to analog pins on the
Arduino, which successively measure the
voltage along different points on the Y-axis.
The two sets of lines are separated by a
sheet of Velostat. With the change in voltage
in a Y-axis circuit, as well as data indicating
which X-axis has sent the ping of current at
the moment, location of pressure should be
detectable.
However, this design did not
accurately determine location. The Velostat
works as a continuous resistor, meaning that
the current flows through the entire sheet of
Velostat and creates one large circuit.
The second prototype used the same
design, except divided the sheet of Velostat
into strips. The strips of Velostat run parallel
to the Y-axis. However, this sensor cannot
determine where along the Y-axis sensors
the pressure is applied, instead recording a
change in pressure along an entire pressure
sensor strip. This problem could potentially
be ameliorated by replacing the strips with a
two-dimensional array, or grid, of squares of
Velostat to separate the points. However, a
different and more reliable approach was
used for the final grid.
3.5 Final Design of Pillow Pressure
Sensors
The final implementation of the
pressure sensor utilizes a zigzag pattern of
conductive thread (see Figure 3). This
pattern makes the sensor more reliable. Even
under stress, the conductive threads remain
overlapped to complete the circuit. The
zigzag lines ensure that the two layers of
conducting thread have multiple points of
contact with one another. In the first
prototype, on the other hand, straight lines
of thread must be perfectly aligned or else
Figure 4 The final pillow pressure sensor consisted of seven layers and
two separate X- and Y-axis sensors.
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there is only one point of contact to form a
circuit.
The sensor, like the previous one,
consists of strips of Velostat running parallel
to each line, sewn between two pieces of
fabric embroidered with the zigzag pattern.
However, unlike the former pressure sensor
created for location capabilities, this grid of
sensors employs completely separate X- and
Y-axis sensors. Thus, there are four layers of
embroidered fabric and two layers of
Velostat, separated by a fifth layer of
unembroidered, insulating cloth (see Figure
4). The insulating cloth is a piece of plain
black cotton fabric sprayed with Plasti Dip.
The Plasti Dip seals holes in the fabric to
ensure that the X- and Y-axis circuits remain
separate. Unlike the earlier prototypes for the
pillow sensor, the final version does not use
the digital pins of the Arduino. Rather, all
the circuits are connected to analog pins.
Creating the X- and Y-axis sensors
as separate layers improves the accuracy of
the sensor. The sensors record changes in
pressure, and the Arduino interprets the
information as pressure applied at the point
of intersection of the two sensors.
The pillowcase itself is a 26-inch by
20-inch rectangle. Consisting of seven
horizontal and seven vertical zigzag lines of
embroidered thread, the sensor covers a 23.5
by 18 square inch area. This pattern was
designed using AutoCAD to maximize
precision.
3.6 Code for Pillow Pressure Sensors
The sensors take the data for the X-
and Y-axis sensors separately. If pressure is
applied at one point, then the Arduino will
read the change in voltage in the X-axis
sensor and the Y-axis sensor that run
through that point. The computer will locate
the point of intersection of the two activated
sensors and therefore the point of pressure.
Figure 5 The histogram shows the amount of movement over a four-hour sleep period,
while the grid of dots displays the pressure applied on each point on the pillow at a
moment. The two periods of little to no movement, marked in red, represent REM sleep.
REM
REM
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To measure the magnitude of change
in pressure, the data from each sensor is
normalized. Since the sensors were
individually manufactured, the initial
voltage with applied pressure varies for each
sensor. To normalize the data, therefore, the
voltage for each sensor is divided by the
initial voltage to determine the relative
magnitude of pressure.
The code uses these representative
pressure values to track the state of each
point on the pillow. When the normalized
values change, then the state of the
intersection has changed. The user interface
connected to the pillow (Figure 5) displays
these pressure values in the grid of dots,
located in the bottom right corner. Each dot
in the grid changes color depending on the
current amount of applied pressure. These
dots aid users in visualizing their
movements in sleep.
Meanwhile, the histogram depicts
the magnitude of change in state of the
sensor over time. A Y-value of zero
represents constant pressure on an
unchanging location, while large spikes in
the graph demonstrate significant changes in
pressure or location. As time goes on, the
histogram scales itself to fit the new data.
Every ten minutes, a screenshot is
taken so that users can use the visual grid of
pressure in the GUI to diagnose sleeping
disorders. For example, somnambulism can
be suggested by a total lack of pressure on
the pillow for an extended amount of time.
4 Results
4.1 Pillow Sensor Testing
The final sensor was sewn into a
pillowcase (see Figure 6) and tested
overnight. A four-hour sleep period
demonstrates the efficacy of the pillow. The
histogram’s data taken from this period
shows two sleep cycles, as expected given
the amount of sleep. These cycles are
defined by the two periods of lack of
movement during which the user was in
REM sleep (see Figure 5). The test proved
both that the sensors can sense movement
and that the sensors can measure sleep
Figure 6 The final sensor was sewn inside a pillowcase and wired to the
Arduino Mega.
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cycles. With more time, more testing would
be completed to reinforce the data.
4.2 Sensor Improvements
If this product were to be improved
and developed in the future, the method of
locating position of pressure should be
replaced with a more precise approach.
Because the sensor’s coordinate grid
determines the X- and Y-positions
independently from one another, it cannot
accurately pinpoint two or more
simultaneous applications of pressure. If
pressure drops in the second and fourth
sensors parallel to the X-axis, and in the first
and fifth sensors parallel to the Y-axis, then
the sensor cannot determine whether the two
points are (2, 1) and (4, 5) or (2, 5) and (4,
1). Instead, it recognizes and records all four
points of possible contact, both the two
actual points of contact and the two “ghost
points” (see Figure 7) [14].
While the sensor cannot accurately
delineate between points of pressure and
ghost points, this has little detriment to
measurement of movement, as changes in
pressure on the same points are also
measured and the sensors are closely spaced.
Therefore, head movement should in one
way or another change the location of
applied pressure.
4.3 Interface Development
In addition to the improvements to
the pressure sensor designs, the interface
displaying the sensor data could also be
expanded to analyze the data and provide
users with relevant data. For example, the
sensor data could be further analyzed to
label periods of light or deep sleep on the
histogram.
If anomalies such as a time of zero
pressure were to occur in the data, then the
code could track these abnormalities and
Figure 7 When two or more points of pressure are applied, the Arduino
cannot recognize the exact intersections of the X- and Y-axis sensors, so
records extra “ghost points”.
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alert the user in the morning. Consistent
atypical data could be further analyzed and
used to recommend solutions for better sleep
to users.
4.4 Cost Analysis
The cost of an e-textile pillow, while
partially dependent on the fabric and
particular thread used, far undercuts the cost
of other sleep tracking wearable devices.
The silver-coated nylon thread used
in this research endeavor costs 41.95 dollars
for 1.92 ounces of thread, which equates to
approximately 350 meters of length [14].
The useable length of the thread is
quadruple this length, or 1400 meters, as the
four-ply thread was split into its separate
strands for use in the sewing machine;
therefore, the cost per meter of thread is
approximately 12 cents. The cost of an 11-
inch by 11-inch sheet of Velostat is four
dollars, meaning that per square inch, the
cost of Velostat is approximately 3.3 cents
[15].
The particular pillow created in this
paper used plain black and red cotton fabric,
which may vary in cost depending on the
quality of the fabric: its design, dye, ply,
durability, softness, and other uncontrolled
qualities. The sensors require approximately
30 meters of thread, costing 3.60 dollars; the
resistive strips use approximately 275 square
inches of Velostat, costing 9.08 dollars.
Assuming a cost of five dollars per yard of
cotton fabric, the body of the pillow costs
four dollars and the sensor fabric costs 6.50
dollars. Therefore, the final cost of
manufacturing the pillow comes to just
under 24 dollars.
In comparison, other sleep tracking
devices such as the Misfit Shine cost 70
dollars, while the Withings Aura sleep
tracker costs 300 dollars [13].
5 Conclusions
5.1 Summary of Findings
The pressure sensors made are
inexpensive and relatively simple, making
them easy to produce in mass with a high
margin of profit. However, they do not
accurately pinpoint location because the X-
and Y-coordinates are given independently
of one another. If e-textile temperature or
motion sensors were incorporated into the
pillow, then it would be more accurate in
tracking sleep. In addition, if the location
inaccuracies of the pressure sensor are
solved, then these sensors can be used for a
variety of other applications.
5.2 Future of E-Textiles in Sleep
Industry
Due to time constraints, this research
focused on one particular type of e-textile
sensor. Yet, not only may pressure sensors
be integrated into pillows for monitoring
sleep, but also other sensors may be
incorporated into sheets and pajamas for
more accurate and in-depth sleep tracking.
For example, e-textile pajamas for infants
could monitor heart-rate and respiration to
guard against Sudden Infant Death
Syndrome [2]. For other users, temperature
sensors in pajamas may be used to further
determine in which part of the sleep cycle
users are, as temperature drops during sleep
and falls even further during the REM stage
of sleep [16]. Motion sensors integrated into
pajamas would also provide more accurate
readings for movement during sleep.
Additionally, sweat sensors or motion and
pressure sensors sensitive enough to detect
shivering and goosebumps could also play a
role in ensuring a comfortable sleep, as the
sensors could be wirelessly linked to
temperature controls in the bedroom. The
pajamas themselves could heat or cool at the
subtle signals of the sleeping user.
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5.3 Future of E-Textile Pressure
Sensors
The application of the e-textile
pressure sensors in other fields is also
promising. In police uniforms, these sensors
could provide data proving whether a police
officer on trial was actually assaulted before
retaliating in cases of alleged police
brutality. The sensors made in this endeavor
have the ability to detect the amount of
pressure and location of pressure. Combined
with capacitive touch sensors, the police
uniform could also determine the difference
between the impact of a human fist or of a
blunt object.
Pressure sensors may also play a role
in clothing sensors for the elderly to contact
an ambulance should they fall down. These
sensors would detect sudden large amounts
of force applied to typical points of impact
in a fall and contact emergency medical aid
[2].
Another pressure-specific application
is in discreet “buttons” sewn into clothing or
bags. These buttons could connect
wirelessly to a variety of devices: they could
work recreationally by playing/pausing
music from one’s phone, or they could work
practically by alerting the authorities of
users’ locations if they feel threatened or are
in danger.
Worked into socks or shoes, these
sensors could alert users of podiatric issues
such as pronating or supinating, as well as
analyzing gait. In this way, athletes and
recreational runners would be able to
recognize improper running techniques such
as heel-striking without the inconvenience
of a doctor’s visit.
5.4 Significance of E-Textiles
In summary, the development of e-
textile sensors and technology will greatly
change daily life. E-textile pressure sensors
alone hold multifarious applications, from
monitoring sleep to detecting aggression or
falls. Additionally, heart-rate and respiration
sensors will encourage healthier lifestyles
and GPS tracking e-textiles will keep users
safe. Uniquely flexible, unobtrusive, and
inexpensive, e-textiles are a promising field
of research.
6 Acknowledgements
It should be noted that this research
paper and project would not have been
possible without the guidance and support of
many mentors, who sacrificed their time and
freely gave their knowledge, and the funding
of many generous sponsors, who donated
significant amounts of money to make this
summer program viable. The authors of this
paper first extend their sincere thanks to the
people who oversaw the organization and
fruition of this program: Dean Ilene Rosen,
Director of the New Jersey Governor’s
School of Engineering and Technology
(GSET), and Dean Jean Patrick Antoine,
Associate Director of GSET. Without their
dedication to running and maintaining the
GSET program, none of the resources
provided for this project would be
attainable. In addition, the authors owe their
learning and progress to the mentors of this
research endeavor: Dr. Aaron Mazzeo,
Assistant Professor of Mechanical &
Aerospace Engineering, and Mandev Singh,
Rutgers Class of 2019, Mechanical &
Aerospace Major. From providing
inspiration and resources to patiently
guiding this project in producing a tangible
and impactful final product, they played an
integral part in the research and
development process described in this paper.
Furthermore, gratitude is owed to all the
residential teaching assistants of GSET, in
particular Jihoon Oh, who oversaw the
progress of this research project, and
Anthony Yang, who provided valuable help
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in times of need. The authors also
wholeheartedly thank the many sponsors of
GSET: Rutgers University, Rutgers School
of Engineering, Lockheed Martin, South
Jersey Industries, and Printrbot.
7 References
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technologies/
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polymer-based devices for e-textiles in
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[3] (2012, February 22). Why is Sleep
Important? [Online]. Available:
http://www.nhlbi.nih.gov/health/health-
topics/topics/sdd/why
[4] (2015, September 3). Insufficient Sleep is
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Available:
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