Conference Session C3
Paper 6188
Disclaimer — This paper partially fulfills a writing requirement for first year (freshman) engineering students at the
University of Pittsburgh Swanson School of Engineering. This paper is a student, not a professional, paper. This paper is
based on publicly available information and may not be provide complete analyses of all relevant data. If this paper is used
for any purpose other than these authors’ partial fulfillment of a writing requirement for first year (freshman) engineering
students at the University of Pittsburgh Swanson School of Engineering, the user does so at his or her own risk.
THE USE OF POLYDIMETHYLSILOXANE (PDMS) MICROSYSTEMS IN
ARTIFICIAL SKIN TO SIMULATE A SENSE OF TOUCH
Sadhana Tadepalli, slt71@pitt.edu , Mahboobin 4:00pm , Isreal Williams, icw6@pitt.edu, Vidic 2:00pm
Revised Proposal — This paper explores the application of
polydimethylsiloxane (PDMS) in artificial skin to improve
prosthetic limbs. It is proposed that artificial skin using
PDMS best restores sense of touch in the skin created to
cover a prosthetic limb. Its flexibility and sensitivity, and
durability make it an ideal foundational microsystem when
creating “electronic skin”.
One of the biggest drawbacks of prosthetic limbs is that
one cannot feel that body part once it has been lost. Thus, it
has been a goal to create artificial skin that better replicates
human skin in more biologically practical sense. Recreating
this sensation goes beyond trying to make a luxury, as the
sense of touch is essential to human safety. It functions as one
of the body’s first alarms against physical damage, and helps
prevent infection. A study of prosthetic limbs usage reports
that approximately 1 in 190 persons in the year 2005 have a
prosthetic limb. Within 5 years, that number has risen to
approximately 1 in 170. By 2050, the number is expected to
increase to 1 in 95[1]. Given this projection, the amount of
people who would walk around with an increased chance of
sustaining an injury without the human sense is alarmingly
large, and the demand for “e-skin” is significant [2].
However, collaborative efforts from universities the world
over may be reaching a solution. Getting closer to
understanding the processes which occur in the human body
has allowed researchers to connect materials, like PDMS, to
sensors that allow communication between the artificial skin
and brain.
Synthetic skin must be capable of performing basic
tasks, such as grasping and squeezing, without ruining the
integrity of the skin, or overloading the brain. To do this
engineers conduct laboratory tests. Comparing the results of
these tests, it has been found that PDMS can effectively relay
information between circuitry of the sensors and also as the
epidermal layer, repeatedly [3]. Additionally, the low cost of
production serves as another argument for the
implementation of PDMS [1].
In order to properly assess the role of PDMS in the
advancement of artificial skin, we will review other materials
used for artificial skin and their effectiveness. The
development of artificial skin will also be holistically
summarized to show how it has evolved, specifically focusing
on how the implementation of PDMS and its impact for
artificial skin. From this, we will validate the effectiveness of
University of Pittsburgh Swanson School of Engineering 1
2016/01/29
PDMS, maintaining the claim that it is the best material to
use in order to make artificial skin. It has the potential to be
as human as possible, while having the power to work with
sensors, communicate with the brain, and perform tasks much
like natural skin.
REFERENCES
[1] K. Ziegler-Graham, E. MacKenzie, P. Ephraim, et al.
(2008). "Estimating the Prevalence of Limb Loss in the
United States: 2005 to 2050." Science Direct. (online article)
[2] G. Schwartz, B. Tee, J. Mei, A. Appleton, et al. (2013).
"Flexible Polymer Transistors with High Pressure Sensitivity
for Application in Electronic Skin and Health Monitoring."
Nature Communications. (online journal).
[3] L. Griscom, Y. Chateau, J. Pennec, L. Misery, B. Pioufle,
(2005). "Co-culture of cells in PDMS microsystem for
sensitized artificial skin," 3rd IEEE/EMBS Special Topic
Conference on Microtechnology in Medicine and Biology,
pp.184-187, 12-15
[4]C. Lucarotti, et al., (2013). “Synthetic and Bio-Artificial
Tactile Sensing: A Review.” Sensors, (online review).
ANNOTATED BIBLIOGRAPHY
C. Arnaud, (2015). "Artificial Skin Sends Touching Signals
to Nerve Cells." Scientific American. (online magazine
article).
This article, posted on an online technology magazine,
reports on the newly made “electronic skin” produced at a lab
at Stanford university headed by Zhenan Bao. The article
focuses on how they used pressure sensors and converted
them to electrical pulses so that the brain can understand. It
also discusses the potential benefits it has for the future of
prosthetics as it is a huge development in this field.
D. Cheneler, (2014). "A Bio-Hybrid Tactile Sensor
Incorporating Living Artificial Skin and an Impedance
Sensing Array." US National Library of Public Medicine.
National Institutes of Health, (online article).
This article was published on an online, peer edited open
access journal, which is dedicated to articles and papers about
sensors. It discusses the bio-hybrid tactile sensor, a type of
Sadhana Tadepalli
Isreal Williams
sensor that has been engineered to work in artificial skin. One
of its components is polydimethylsiloxane (PDMS), so its
role in this specific sensor can be evaluated. It was
determined that PDMS did act effectively as an epidermis
layer.
University of Pittsburgh ULS. (2014). “A Current, Significant
Engineering Topic” (Video)
This is an online tutorial video regarding the picking and
writing of a conference paper. It is made and provided by the
writing instructor staff at the University of Pittsburgh. It goes
step by step as to how to decide on a topic to write about and
finding appropriate research using online sources. This was
helpful when deciding what to write the conference paper
about.
L. Griscom, Y. Chateau, J. Pennec, L. Misery, B. Pioufle,
(2005). "Co-culture of cells in PDMS microsystem for
sensitized artificial skin," 3rd IEEE/EMBS Special Topic
Conference on Microtechnology in Medicine and Biology,
pp.184-187, 12-15
This publication reports the finding of various researches
at a medical and scientific conference from 2005. The most
applicable
finding
is
the
tests
conducted
on
polydimethylsiloxane (PDMS) polymer, which we will use to
assert the argument in favor of using PDMS. PDMS has been
tested with the intent to create artificial nerve endings and
relay information to the brain after detected by artificial skin.
K. Ziegler-Graham, E. MacKenzie, P. Ephraim, et al.
(2008). "Estimating the Prevalence of Limb Loss in the
United States: 2005 to 2050." Science Direct. (online article).
This online article, published on the US National Library
of Medicine’s website, reports on a study about limb loss.
This information will be used to give statistics about limb
loss to show the need for prosthetics and its development. It
is said that by 2050, it is expected that 1 in 95 people will
have lost limbs, indicating that proper prosthetics will be
more in demand for the future.
S. Halim, S.Yahud, W. Muhamad, R. Daud, N. Zain, (2015).
“The application of finite element analysis on
polydimethylsiloxane” AIP Conference Proceedings, 1660,
070004, (conference paper).
This conference paper, published in 2014, evaluates the
material of polydimethylsiloxane, which is the polymer that
our conference paper will be about, with regards to artificial
skin. It specifically tests the material’s ability to stretch and
sees how it reacts to stress in order to determine if it would be
viable material to replicate human skin as close as possible,
which is something our paper wants to determine overall.
C. Lucarotti, C. Oddo, N. Vitiello, M. Carrozza, (2013).
“Synthetic and Bio-Artificial Tactile Sensing: A Review”.
Sensors. (online review).
This review, published by an online, peer edited journal
that focuses on sensors, discusses the need for artificial
sensing in regards to synthetic skin and bio-artificial skin. It
compares and contrast the different sensors that can be used.
The most useful part of this review is the discussion it has
about the overall need for artificial skin and how it should be
implemented, as our paper will discuss this.
G. Schwartz, B. Tee, J. Mei, A. Appleton, et al. (2013).
"Flexible Polymer Transistors with High Pressure Sensitivity
for Application in Electronic Skin and Health Monitoring."
Nature Communications. (online journal).
In order to ensure that PDMS would improve the artificial
skin’s ability to convey touch, teams of engineers subject the
microsystem to various experiments and help produce a
measure of sensitivity. Results from these experiments such
as one published by Nature Communications, during in which
PDMS undergoes tests at various pressures and its sensitivity
is recorded, can help support the claim that using
polydimethylsiloxane would improve the ability of artificial
organ’s ability to restore the sense of touch to an area around
a prosthetic limb.
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