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AN INOVIETIVE WAY TO IMITATE HUMAN TOUCH
Table of contents
Introduction.......................................................................................................................... 2
Literature review .................................................................................................................. 3
Project Goal .......................................................................................................................... 4
Project description ............................................................................................................... 4
Overall design& characterization ..................................................................................... 4
Method of fabrication ........................................................................................................ 6
Application ......................................................................................................................... 6
Conclusion and recommendations:...................................................................................... 8
Reference .............................................................................................................................. 9
Abstract
Human skin is a remarkable organ. It consists of an integrated, stretchable network of
sensors allowing us to maneuver within our environment safely and effectively. Interest in
large-area networks of electronic devices inspired by human skin is the motivation to
creating electronic skin for medical diagnostics, among other applications.
E-skin, an electronic skin device is an electronic network that form flexible and stretchable
devices who is compatible with large-area implementation and integrated with multiple
functionalities to imitate human touch. Furthermore, e-skin has developed to be a sensitive
device that is able to sense objects that the human touch sense cannot.
E-skins are already capable of providing increased performance in all life aspect, from
innovative technology, many smartphone function can been done from a fingertip with an
e-skin device implementation and it goes further to the health care filed to discover cancer.
Those devices could be further improve through the innovative research and in the near
Future additional functionalities can be preform via e-skin devices.
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Introduction
Human skin is the most visible and complex part of our body and even though it is easy to
neglect the complexity of the largest sensory organ in our bodies. Our skin is the physical
barrier through which we interact with our surroundings, allowing us to perceive various
shapes and textures, changes in temperature, and varying degrees of contact pressure.
To achieve such high sophistication in its sensing capabilities, several different types of
highly specialized sense receptors are embed within our skin. These receptors first
transduce information generated by physical contact into electrical signals and
subsequently send it to the central nervous systems for more complex processing.
All those signals are interpret by our brain so we successfully navigate in our physical world
with ease.
The effort to create an artificial skin with human-like sensory capabilities is motivate by the
possibility of such large, multi-sensory surfaces being highly applicable for medical
diagnostics. Sensor skins applied on or in the body could provide an unprecedented level of
diagnostic and monitoring capabilities. The electronic skin is able to determine tumors at
sizes four times smaller than can be detected by the most skilled health care provider
during physical examination.
One example of the benefits that human race can gain of this type of sensor is the
detection of small cancerous growths like breast cancer. Breast cancer is the most common
cancer in women worldwide. Studies have proved that early detection is the key to breast
cancer survival. In addition, the smaller the tumor when discovered, the better the chance
it has not spread nearby tissue. Now a days doctors use clinical test and other simulation
tests like mammogram or MRI to detect lumps but as trained and gifted the doctors will be
they cannot usually detect lumps smaller than 21mm while examine a patient.
For clarification, the American Cancer Society published that a 94% survival rate is possible
if the tumor will be detect at less than 10mm.
Those facts demonstrate the importance of a device that will be able to detect tumors as
tiny as possible and hence the highly importance of e-skin devices development.
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Literature review
"Imperceptible magneto-electronics" by Michael Melzer, Martin Kaltenbrunner, Denys
Makarov, Dmitriy Karnaushenko, Daniil Karnaushenko, Tsuyoshi Sekitani, Takao Someya
& Oliver G. Schmidt), in this article the author specifically the Future electronic skin
characteristics that aims to mimic the original skin in both functionality and appearance.
Although some of the multifaceted properties of human skin may remain exclusive to the
biological system, electronics opens a unique path that leads beyond imitation and could
equip us with unfamiliar senses. In addition, the article demonstrate giant magneto
resistive sensor foils with high sensitivity, unmatched flexibility and mechanical endurance.
"Human touch" by Leslie Reed, in this article the author describe how nanoparticle sensor
could improve breast cancer detection.
This paper shows a more specific research in the e-skin field by scientists from NebraskaLincoln University, Saraf and Nguyen. In their research, they developed a nanoparticlebased device that emulates human touch and when pressed against the skin creates
changes in electrical current that can be capture by a high-quality digital camera. The
nanoparticle film, just one-60th the thickness of a human hair, is a sort of "electronic skin"
able to sense texture and relative stiffness. The model can successfully detect tumors as
small as 5 millimeters, hidden up to 20 millimeters deep. This technology allow improved
detection for skin cancer and could significantly enhance clinical breast exams for early
detection of cancer.
" Paper-thin e-skin responds to touch " by Sarah Yang from the Media
Relations department on Berkley university review the research of a team led by Ali Javey,
associate professor of electrical engineering and computer sciences and UC Berkeley coauthors on this study: David Hwang, Zhibin Yu and Kuniharu Takei.
This research holds promise for sensory robotics and interactive environments and include
the details for the first user-interactive sensor network on flexible plastic. The e-skin,
responds to touch by instantly lighting up, the more intense the pressure, the brighter the
light it emits. Furthermore, it explained the main approach for fabrication and
characterization required.
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Project Goal
Innovative sensing tools have been development that make use of nanotechnology to
detect and monitor various elements in personal or professional life. It opens up the
possibilities for infinite innovative applications, starting from diagnosis and treatments of
diseases, continuing with quality control of goods and environmental aspects, and ending
with monitoring security issues.
A fascinating idea is the possibility to imitate the human senses by means of
nanotechnology and nanoscale sensors. For example, artificial skin with human-like sensory
capabilities being highly applicable for medical diagnostics is a breakthrough in cancer early
discovery.
The main goal of making an electronic skin is that it can "feel" and images small lumps that
fingers can miss. Knowing the size and shape of a lump could allow for earlier identification
of cancer, which could save lives. The electronic skin is able to determine tumors at sizes
four times smaller than can be detected by the most skilled health care provider during
physical examination. Another great advantage of the device is its ability to record the
images so that they will be included in the patient’s medical records and that it provides
results right away.
Project description
Overall design& characterization
Human skin is the inspiration for artificial skin systems. Artificial skin, also known as e-skin
imitate skin function but should be much more sensitive to discover and sense elements
that the human skin cannot. For this demand to be completed e-skin design should consist
a fully research for all the materials- nanoparticles and polymers that will be used in the
fabrication.
The research that should consist the materials mechanical properties to ensure that they
are similar to the properties of human skin (e.g. flexibility and stretch ability). Equally
important is the ability of human skin to cure itself, artificial skin should be able to do the
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same with at least equal or higher quality, allowing it to last a lifetime. Other desirable
properties, including biocompatibility and biodegradability, self-healing and temperature
sensitivity. To achieve these properties, the choice of materials is critical, and technological
advancements in e-skin have been largely possible through the development of new
materials and processing methods for the fabrication of stretchable and flexible devices.
In addition, good electrical performance and compatibility with large-area processing
techniques are important to create highly functional, low-cost devices.
Nanomaterials often provide an advantageous combination of physical properties and cost.
The e-skin also need to be durable for all kind of forces such as normal, shear and bending
as illustrating in the picture below:
Another factor that need to be revise is developing e-skin hardware, who its true value is
derive from effective digitization, which requires software to provide a communication
interface with the user. The signals produced from sensors in e-skins are analog, and signal
digitization is required for interfacing with modern digital microprocessors.
Ideally, digitization would be a process that does not require considerable power
consumption. After digitization, software algorithms need to process and interpret the large
amounts of data.
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Method of fabrication
Following from the demands above E-skin should be a network of mechanically flexible
sensors that can be wear or implement.
A thin and interactive sensor network that will be able to arrange in a layered form on a
surfaces of virtually any shape. The device should give out immediate feedback when
touched.
A research team at Berkeley University have created a matrix of interactive pressure
sensors that response to touch with light, the intensity of the light is proportional to the
pressure. Unlike a stiff iPhone touchscreen, this system is highly flexible and can be easily
laminated onto any surface, no matter how geometrically complex.
The fabrication consist of a thin layer of polymer on
top of a silicon wafer and then used standard
semiconductor manufacturing techniques to layer in a
transistor, an organic LED and a pressure sensor on
top of each other. Finally, they simply peeled off the
plastic from the silicon base, leaving a freestanding
film with a sensor network embedded in it.
Their result was a matrix of 16 by 16 sensors that is
highly interactive with a response time of just one
millisecond.
Application
The main purpose of e-skin is to make life easier and more comfortable as possible just like
the main purpose of Nano sensors in general; e-skin can be a great use for medical devices
in multiple areas and especially in the cancer discover field since this area demand accuracy
above all things.
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Ravi Saraf and Chieu Van Nguyen, scientists at the University of Nebraska, have suggested
an innovative design for e- skin. They have created an electronic skin that can detect lumps
as small as 5mm and as deep as 20mm into the tissue. The electronic skin device, which is
about 150nm thick, has many layers comprised of nanoparticles and polymers. It is
fabricated layer-by-layer using the following polymers: PAH and PSS to create a thin-film
tool.
Their research is a significant breakthrough, early detection of breast cancer could save the
lives of many people because it is a known fact that early detection of cancer and especially
breast cancer is among the most important factors for survival.
The electronic skin is able to determine tumors at sizes four times smaller than can be
detected by the most skilled health care provider during physical examination.
An illustration shown in the image below:
The device held against the skin, capture an image with a high-resolution camera,
an image of the tissue that show any abnormalities.
The device has been optimized for sensitivity in order to provide high quality images
without the need for uncomfortable pressure on the breast so the patient will feel as
comfortable as possible, a very important factor to consider because breast test is an
inconvenient situation as it is.
According to Saraf and Nguyen the team is now building the first prototype of the device, it
will take about a year to build and cost an estimated $1.5 million.
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Conclusion and recommendations:
E-skin development has accelerated dramatically in the past few years since new materials
and processes has developed. This progress e-skin functions are rapidly converging with
those shown in science fiction movies.
e-skin design require a lot of different aspect, it begin with the materials that need to be
choose in a way to ensure all demands are fulfill, the structure should be well designed and
another important factor is the data analyzer that need to consist a solid and reliable
software.
As described e-skin is an important tool that can contribute a lot to the population of the
world in all kind of field and especially in the health care area. The rapid pace of progress
in e-skin technology suggests that the fabrication of a more complex e-skin with progress
properties will soon be possible.
Nonetheless, the road of developing a practical e-skin for all is not short. Now it is a high
cost technology and not accessible for the majority hence it is crucial to keep investigate
and research for a low cost materials that fulfill all requirements. Furthermore, society in
general and the science community in particular souled raise the awareness on this
innovative field because it is certain to be a great thing to humanity.
In conclusion, e-skin devices will be a great news to all people worldwide, it will save many
lives and improve life beyond recognition, since the main propose of sensors is to make life
easier, e-skin is an important news on the Nano sensors field.
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Reference

Melzer, M., Kaltenbrunner, M., Makarov, D., Karnaushenko, D., Karnaushenko, D.&
Sekitani, T. (n.d.). Imperceptible magnetoelectronics. NATURE COMMUNICATIONS.
Retrieved January 21, 2015,
From
http://www.nature.com/ncomms/2015/150121/ncomms7080/full/ncomms7080.html

Chieu Van Nguyen and Ravi F. Saraf
Department of Chemical and Bimolecular Engineering, Nebraska Center for Materials
and Nanoscience, University of Nebraska—Lincoln.
Publication Date (Web): August 22, 2014. American Chemical Society
http://pubs.acs.org/doi/abs/10.1021/am5046789

Leslie Reed. "'Human Touch' Nanoparticle Sensor Could Improve Breast Cancer
Detection." 'Human Touch' Nanoparticle Sensor Could Improve Breast Cancer
Detection. University of Nebraska-Lincoln, 11
Sept. 2014.

Yang, Sarah. "Paper-thin E-skin Responds to Touch, Holds Promise for Sensory
Robotics and Interactive Environments." UC Berkeley News Center. Media Relations,
21 July 2014

"New 'electronic Skin' for Prosthetics, Robotics Detects Pressure from Different
Directions." New 'electronic Skin' for Prosthetics, Robotics Detects Pressure from
Different Directions. Phys.org, 10 Dec. 2014
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