I love living in the future.
Dec. 3rd, 2009 03:17 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
theweaselking"Debregeas et amis say it looks as if the ridges and whorls in fingerprints filter mechanical vibrations in a way that best allows nerve endings to sense them. The mechanoreceptors that do this job are called Pacinian corpuscles. They sit at the ends of nerves and are responsible for sensing pressure and pain. These devices can sense vibrations over a wide area of skin but are sensitive only to a limited range of vibrations. In fact biologists have known for some time that Pacinian corpuscles are most sensitive to vibrations at 250Hz.
Debregeas and co have investigated this problem using a "CYBER FINGER" that they built in their lab, complete with synthetic fingerprints on the same scale as human ones and a microelectromechanical sensor that measures force with a spatial resolution of millimetres. They say that fingerprints resonate at certain frequencies and so tend to filter mechanical vibrations. It turns out that their resonant frequency is around 250Hz.
That means that fingerprints act like signal processors, conditioning the mechanical vibrations so that the Pacinian corpuscles can best interpret them. It's this optimisation process that allows us to sense textures with a spatial resolution far smaller than the distance between Pacinian corpuscles in the skin.
There is a growing awareness that the processing power of the nervous system, including the brain, simply cannot handle the volume of number crunching that has to be done to keep a living body on the road. Instead, it looks increasingly clear that the brain outsources much of this work to the body itself: to the joints, ligaments, muscles, skin etc. Understanding how these materials do all this processing is turning materials science into a branch of computer science. It's even got a name: morphological computing. "
Debregeas and co have investigated this problem using a "CYBER FINGER" that they built in their lab, complete with synthetic fingerprints on the same scale as human ones and a microelectromechanical sensor that measures force with a spatial resolution of millimetres. They say that fingerprints resonate at certain frequencies and so tend to filter mechanical vibrations. It turns out that their resonant frequency is around 250Hz.
That means that fingerprints act like signal processors, conditioning the mechanical vibrations so that the Pacinian corpuscles can best interpret them. It's this optimisation process that allows us to sense textures with a spatial resolution far smaller than the distance between Pacinian corpuscles in the skin.
There is a growing awareness that the processing power of the nervous system, including the brain, simply cannot handle the volume of number crunching that has to be done to keep a living body on the road. Instead, it looks increasingly clear that the brain outsources much of this work to the body itself: to the joints, ligaments, muscles, skin etc. Understanding how these materials do all this processing is turning materials science into a branch of computer science. It's even got a name: morphological computing. "