Some prosthetic limbs are so advanced they can be controlled by the brain, but no bionic arm or leg will ever be truly be life-like until they have “skin” that can feel. This new artificial skin developed by a team of American and Korean researchers, for instance, has a dense network of sensors made of silicon and gold that mimic the sensitivity of real skin. The amount of sensors present is important, because as Roozbeh Ghaffari said: “If you have these sensors at high resolution across the finger, you can give the same tactile touch that the normal hand would convey to the brain.”