Making artificial limbs that can perform gross motor functions is relatively easy. Fine motor actions are harder, and wiring the limbs into the nervous system is harder still. But researchers at Berkeley and Stanford are crossing the real frontier: making artificial skin that can touch and feel.
Research teams at Berkeley and Stanford recently announced breakthroughs in producing highly touch-sensitive artificial skin. In both cases, an extremely thin layer of plastic or rubber is bonded to electronic elements arranged in micropatterns, so the skin can retain flexibility and elasticity while still transmitting a strong signal. The papers appear in an forthcoming issue of the journal Nature Materials.
At Berkeley, the team used germanium-silicon nanowires, which they compare to microscopic “hairs” on the filmy plastic skin. The Stanford team paired electrodes in a pyramid pattern, which communicate through a thin rubber film (total thickness of the artificial skin, including the rubber layer and both electrodes: less than one millimeter). They also created a flexible transistor, again to retain elasticity.