They have combined a mini projector which creates a changing display with a sophisticated sensor that can tell which part of your arm is being tapped.
The researchers showed Skinput can be used to control audio devices, play simple games like Tetris, make phone calls and navigate simple browsing systems.
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Skinput could solve the problem of ever shrinking gadget screens
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‘The project is going very well and I think you’ll begin to see such interfaces emerge within the next five years.’
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Different skin locations are acoustically distinct because of bone density and the filtering effect from soft tissues and joints. The team then used software that matched sound frequencies to specific skin locations.
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The armband prototype can be combined with an MP3 player and used to change the song or volume level
If the prototype isn’t resting on the arm, it uses wireless technology like Bluetooth to transmit the commands to the device being controlled, such as a phone, iPod, or computer.Writing in a paper for Microsoft Research, Chris Harrison, Desney Tan and Dan Morris, said: ‘Our skin has been overlooked as an input canvas and is one that happens to always travel with us.
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‘We can readily flick each of our fingers, touch the tip of our nose, and clap our hands together without visual assistance.’
The sensor picks up two two types of acoustic signals – transverse waves created by the rippling of skin as it’s tapped and longitudinal waves that travel through the soft tissue of the arm and excite the bone.
Currently, the acoustic detector can detect five skin locations with an accuracy of 95.5 per cent, which would be high enough for many smartphone applications.
Mr Harrison told the Mail Online: ‘We achieved high input accuracy in the lab with about one error in 20 key presses, which is similar to what you might find on an iPhone keyboard.’
Twenty volunteers who have tested the system said they found it easy to navigate. The researchers added that Skinput also works well when the user is walking or running.
There are many potential markets for the device. Mr Harrison said: ‘One example is an audio player on your upper arm. Perhaps it has no buttons at all, and only uses the skin as the finger input canvas.
‘You could then just tap your fingers to advance to the next song, change the volume, or pause the current song. You wouldn’t even need a projector for most of these types of interactions.’
The researchers plan to present their work in April at the Computer-Human Interaction meeting in Atlanta, Georgia.
Link From Impact lab