In a series of demonstrations, scientists at Seoul National University’s Multiscale Biomimetic Systems Laboratory showed off a pressure-sensing membrane that is sensitive enough to feel the fall of water droplets, a human pulse in the wrist, and even the whisper-light tread of a lady-bug walking across the “electronic skin.”
True to its “biomimetic” creed, the group took its cue from the signal transduction systems found in the ear, intestines, and kidney—nanoscopic hairs that interlock and produce signals by rubbing one another when their base membranes dent, ripple, or twist. They also added a self-assembly feature inspired by the locking mechanism on a beetle’s wing.
A touch, push, or twist of the basement membrane makes the meshed nanohairs rub and bend, and the changing current shows what’s going on. Indeed, since orthogonal pressure, lateral shear, and torsion produce different response curves, the device can tell the difference between a push, a rub, and a twist.
In sum, the researchers say, the “nano-interlocking mechanism requires no complex integrated nanomaterial assemblies or layered arrays, thus allowing a simple, cheap, yet robust sensing platform for high-performance, large-area strain-gauge sensors.”