A new type of sensor could lead to the creation of a skin type artificial that can help burn victims and better protect certain categories of citizens who are particularly exposed due to their professional activities: at an advanced stage of development, it was presented in an article that appeared in Advanced Materials.
The ability of the skin to sensing pressure, vibration, heat and cold are critical to ensuring safety, a function that most people take for granted: those who have suffered burns or who, for whatever reason, have lost skin sensitivity often injure themselves unintentionally.
Chemists Islam Mosa and James Rusling of the University of Connecticut and engineer Abdelsalam Ahmed of the University of Toronto are developing a sensor that can mimic the sensory properties of the skin, but not only that. “It would be very nice,” Mosa said, ” if the new artificial skin could also incorporate capabilities that natural human skin does not possess, such as the ability to detect magnetic fields, sound waves and abnormal behavior.
The team created a prototype sensor with a silicon tube wrapped in copper wire and filled with a special fluid made of tiny iron oxide particles just a billionth of a meter long. The collisions of the nanoparticles inside the silicone tube create an electric current, and the copper wire picks it up as a signal. When the tube is bumped by something that produces pressure, the nanoparticles move and the electrical signal changes. Sound waves are transmitted in the nanoparticle fluid, and again the electrical signal changes, but in a different and recognizable way.
The researchers found that magnetic fields also alter the signal in a way distinct from pressure or sound waves. Finally, when a person wearing the sensor moves, the electric current changes and produces different signals depending on whether he or she is walking, running, jumping or swimming.
This “metal skin” might appear to be a super-power similar to those possessed by comic book heroes, but researchers have designed it to help burn victims be aware again of the sensations provided by normal human skin and, possibly, help those who, through work, might be exposed to dangerous magnetic fields. The device is completely sealed by the rubber exterior and could also be used in water.
The next step is to change the shape of the sensor so that it takes on a flat, more skin-like configuration and see if it maintains the extraordinary properties shown by the test device.
Ahmed A, Hassan I, Mosa IM, Elsanadidy E, Sharafeldin M, Rusling JF, Ren S. An Ultra-Shapeable, Smart Sensing Platform Based on a Multimodal Ferrofluid-Infused Surface. Adv Mater. 2019 Mar;31(11):e1807201.
