Rub two fingers together and feel the tiny ridges of your fingertips, their texture, their temperature. Our impeccable sense of touch is a constant source of feedback guiding our experience of the physical world. Without it, interaction becomes much harder – a major limitation on many prosthetic limbs. So efforts to recreate skin’s sensing mechanisms are well underway, and now the first artificial nerve able to sense pressure, and even provoke movement, has been attached to living tissue (pictured on a cockroach). The flat, flexible system consists of sensors linked to a ring oscillator, which converts inputs to electrical impulses, and a transistor modelled on human synapses. The arrangement is able to both prompt reflex twitches in a leg, and detect small tactile details. Although a long way off our skin’s sensational sensitivity, this is a first step towards giving prosthetics, or indeed robots, a way to feel the world.
Written by Anthony Lewis
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