The development of a new artificial skin capable of giving touch to the amputees

In a remarkable scientific report, a group of engineers at Stanford University have announced that they have developed a skin-like plastic material that has the ability to sense pressure and send a Morse-like signal directly to nerve cells. This research holds great hopes for amputees, in terms of the possibility of installing prostheses, not only gives them additional motor abilities, but also sensory abilities.

A group of engineers at Stanford University have announced the creation of a plastic material similar to the skin, which can sense the strength of the pressure they are subjected to, and generate an electrical signal that transfers this sensory effect directly to the living cells of the brain.

Stanford University's chemical engineering professor Zinan Bao has spent a full decade trying to create an artificial material that mimics the skin's capabilities, especially the skin's elastic capacity and healing ability. Professor Zinan Bao's research has not only created a flexible skin-like material. Her research has also included how to make the material sensually similar to skin: how it can be included in a sensor network that can capture heat, pressure, and even pain. These signals to the living brain. The ultimate goal of its research is to develop a flexible electronic fabric that can be included with sensors. This fabric is used to cover artificial limbs in order to compensate for some of the sensory abilities of natural human skin.

The new work of Professor Bau and her research team - published in the journal Science - will bring further development in order to achieve the great goal they aspire to: the creation of artificial skin that simulates human skin in the properties of elasticity and sensitivity properties.

"This is the first time a skin-like substance has been developed that has the potential to capture pressure and send a signal that expresses this pressure to a part of the nervous system," says Professor Bau. The research team that worked with Professor Bao consists of 17 people who have all worked to achieve this achievement.

Digitizing Touch

The base stone of this technique is a two-layer plastic structure: the upper layer forms the sensing mechanism, and the lower layer acts as an electric circuit, acting on receiving electrical signals and turning them into biochemical, chemical-compatible, biochemical signals. The upper layer includes a pressure sensor that is able to sense the same area of ​​pressure as human skin, from light touch to a warm handshake.

The next step will be how to read the values ​​of these sensors, and convert it into an electrical form compatible with the nervous system. For this purpose, the team has deployed billions of carbon nanotubes through synthetic plastics. Therefore, when applying pressure to the plastic, this will squeeze the carbon nanotubes closer to each other and make them an electric carrier.

It is these properties that allow the sensor to be an excellent simulator of the human skin, which sends information about the pressure to the brain in the form of electrical pulses similar to the Morse code. Increased pressure applied to the artificial skin means more carbon nanotubes converge, which means allowing more electrical power to cross through the sensor. As a result, the value of the voltage that will result from the pressure of the sensor will be commensurate with the pressure applied to it, so this will generate the mechanism of transmission of information appropriate for the brain.

So far, experiments on the new sensor have succeeded in rat brains, and the team is trying to make this sensor usable on human prostheses, to provide amputees with sensory abilities, as well as the motor abilities given to them by the prostheses.

Sources: IEEE Spectrum - Stanford University