Soft robots have emerged to help humans move items, treat patients, and gather information. But Carnegie Mellon University scientists are trying to make these robots more human-like by giving them the kind of sensing capabilities found in natural soft tissue, according to an article on the university’s website.
The challenge has been trying not to make the presence of wires, which serve to connect a number of sensing points, so obvious. To avoid this hassle, Majidi and Tess Hellebrekers from his Soft Machines Lab at Carnegie Mellon have developed a soft magnetic skin with a single sensing element. Their findings were published in Advanced Intelligent Systems.
"The wires might be fine inside hard cases such as smartphones and other devices, but if you're talking about fabric, skin or something else that's soft, then suddenly all those wires become sources of failure," said Carmel Majidi, an associate professor of mechanical engineering
The soft skin comprises silicone rubber loaded with millions of microparticles that can be placed on robots, natural skin or other surfaces to provide a sense of touch. Each particle has a north pole and a south pole, which creates a magnetic field. When the material makes contact with another object, the rubber detects the move and the microparticles start moving around, thereby changing the internal magnetic field within the rubber.
A magnetometer, an electronic chip embedded in the magnetic skin, measures these changes. The magnetometer can infer the location and intensity of the contact and estimate where the touch is and how hard the touch is pressing on the material's surface.