Electronic skin

Electronic skin or e-skin is a thin electronic material that mimics human skin in one or more ways. Specifically, human skin can sense pressure and temperature, stretch, and can heal itself. Electronic skin aims to apply these functions to robotic and health applications
n February 2011, the Stanford team developed a stretchable solar cell that could be used to power their electronic skin. An accordion-like micro-structure allowed the cells to stretch up to 30% without damage.

Flexible array sensors:

Using organic transistors with a floating gate embedded inhybrid dielectrics that comprise

a 2-nanometer-thick molecularself-assembled monolayer and a 4-nanometer-thick plasma-grown metal oxide, a nonvolatile memory arrays on flexibleplastic substrates is prepared which is used in electronic skin.

The small thickness of the dielectrics allows nonvolatile,reversible threshold-voltage shift. By integrating a flexiblearray of organic floating gate transistors with a pressuresensitive rubber sheet, a sensor matrix that identifies thedistribution of applied mechanical pressure and stores the

analog sensor input as a two-dimensional image over longperiods of time is obtained

Robotic sensors implementing the E-skin techno:

Robots could soon sense heat and pressure through a flexible e-skin, incorporating a matrix of semiconducting sensors or tectile sensors as shown in the figure 7. A flexible electronic skin that can sense when something is too hot to handle or is being squeezed too hard could give robots an almost-human sense of touch. Robots have mastered picking and placing, welding, and similar tasks that can be precalibrated, but they cannot perform tasks that require a sense of touch, such as biotech wizards have engineered electronic skin that can sense touch, in a major step towards next-generation robotics. New electronic skin could give robots human-like touch. Robotics

has made tremendous strides in replicating the senses of sight and sound, but smell and taste are still lagging behind, and touch was thought to be the Impossible. 

Introduction

Electronics plays a very important role in developing simple devices used for any purpose. In every field electronic equipments are required. The best achievement as well as future example of integrated electronics in medical field is Artificial Skin. It is ultrathin electronics device attaches to the skin like a sick on tattoo which can measure electrical activity of heart, brain waves & other vital signals. Evolution in robotics is demanding increased perception of the environment. Human skin provides sensory perception of temperature, touch/pressure, and air flow.
Goal is to develop sensors on flexible substrates that are compliant to curved surfaces. Researcher’s objective is for making an artificial skin is to make a revolutionary change in robotics, in medical field, in flexible electronics. Skin is large organ in human body so artificial skin replaces it according to our need. Main objective of artificial skin is to sense heat, pressure, touch, airflow and whatever which human skin sense. It is replacement for prosthetic limbs and robotic arms. Artificial skin is skin grown in a laboratory.
There are various names of artificial skin in biomedical field it is called as artificial skin, in our electronics field it is called as electronic skin, some scientist it called as sensitive skin, in other way it also called as synthetic skin, some people says that it is fake skin. Such different names are available but application is same it is skin replacement for people who have suffered skin trauma, such as severe burns or skin diseases, or robotic applications & so on. An artificial skin has also been recently demonstrated at the University of Cincinnati for in-vitro sweat simulation and testing, capable of skin-like texture, wetting, sweat pore-density, and sweat rates

     

Architecture of e-skin

With the interactive e-skin, demonstration is takes place an elegant system on plastic that can be wrapped around different objects to enable a new form of HMI. Other companies, including Massachusetts-based engineering firm MC10, have created flexible electronic circuits that are attached to a wearer's skin using a rubber stamp. MC10 originally designed the tattoos, called Biostamps, to help medical teams measure the health of their patients either remotely, or without the need for large expensive machinery. Fig 2 shows the various parts that make up the MC10 electronic tattoo called the Biostamp. It can be stuck to the body using a rubber stamp, and protected using spray-on bandages. The circuit can be worn for two weeks and Motorola believes this makes it perfect for authentication purposes.

 Biostamp use high-performance silicon, can stretch up to 200 per cent and can monitor temperature, hydration and strain, among other medical statistics. Javey's study claims that while building sensors into networks isn't new, interactive displays; being able to recognize touch and pressure and have the flexible circuit respond to it is 'breakthrough'. His team is now working on a sample that could also register and respond to changes in temperature and light to make the skin even more lifelike.

Large-area ultrasonic sensor arrays that could keep both robots and humans out of trouble. An ultrasonic skin covering an entire robot body could work as a 360-degree proximity sensor, measuring the distance between the robot and external obstacles. This could prevent the robot from crashing into walls or allow it to handle our soft, fragile human bodies with more care. For humans, it could provide prosthetics or garments that are hyperaware of their surroundings. Besides adding multiple functions to e-skins, it’s also important to improve their electronic properties, such as the speed at which signals can be read from the sensors. For that, electron mobility is a fundamental limiting factor, so some researchers are seeking to create flexible materials that allow electrons to move very quickly.

Ali Javey and his colleagues at the University of California, Berkeley, have hadsome success in that area. They figured out how to make flexible, large-area electronics by printing semiconducting nanowires onto plastics and paper. Nanowires have excellent electron mobility, but they hadn’t been used in large-area electronics before. Materials like the ones Javey developed will also allow for fascinating new functions for e-skins. My team has developed electromagnetic coupling technology for e-skin, which would enable wireless power transmission.
Imagine being able to charge your prosthetic arm by resting your hand on a charging pad on your desk. In principle, any sort of conductor could work for this, but if materials with higher electron mobility are used, the transmission frequency could increase, resulting in more efficient coupling. Linking sensors with radio-frequency communication modules within an e-skin would also allow the wireless transmission of information from skin to computer—or, conceivably, to other e-skinned people.

Conclusions

The electronics devices gain more demand when they are compact in size and best at functioning. The Artificial Skin is one such device which depicts the beauty of electronics and its use in daily life. Scientists create artificial skin that emulates human touch. According to experts, the artificial skin is "smarter and similar to human skin." It also offers greater sensitivity and resolution than current commercially available techniques. Bendable sensors and displays have made the tech rounds before. We can predict a patient of an oncoming heart attack hours in advance. In future even virtual screens may be placed on device for knowing our body functions. Used in car dashboard, interactive wallpapers, smart watches.