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Transforming Any Flat Surface Into a Control Panel With Sound
New submitter brunozamborlin writes "I just published a short video that shows how a very cheap contact microphone can be used to recognize different types of fingers touch and transform any surface into an interactive board. In the video we put the microphone over different surfaces such as kitchen tables and balloons and through realtime gesture recognition we show how we can play different virtual music instruments using a technique called physical modeling . A mobile version would be definitely possible." The project's Web page shows several more examples. Update: 12/31 15:17 GMT by T : Bruno Zamborlin points out that the surfaces don't need to be flat; instead, they simply need to be rigid.
Do you have to give the system training for the specific purpose and gesture? And could the microphone be on the opposite side of the surface? If so, I think I've got an awesome new way to unlock my door.
It depends what you want to use it for - as a replacement for a touch screen, it's probably not very useful because location information isn't going to be as easy to capture as timbral information, but as a musical instrument (or as a way of adding more sensitivity to existing electronic instruments, it's amazing.
I wonder if accurate position information could be captured by triangulating with 3 of these contact mics?
A pizza of radius z and thickness a has a volume of pi z z a
In the video we see that different gestures are mapped to different sounds. For example the coin enables a certain abstract sound whist the bare fingers enables the bass sound and the nails enables the pad... this is done thanks to gesture recognition techniques (a modified version of Hidden Markov Models to work in realtime). Apologies whether it is not clear enough in the video though...
http://youtu.be/qdJp5-g69go
[spoiler: it's an amusingly-dubbed video of eccentric Canadian hockey announcer Don Cherry, who wears really loud clothes and makes vigorous table thumping gestures]
Depending on how precise it can measure where your 'mouse' is I could see the following happening: ....
1) You build this into a smart phone or tablet PC
2) Calibrate by selecting the 4 corners of your surface.
3) use the whole surface you selected as an extended touch screen.
This could be a bar top, a table at your local fast food, a whiteboard, your desk, tray in a plane,
It would allow the screen to be smaller yet the input to be bigger without the need to drag the keyboard with you. You could use a paper with a pre-printed design on it, like a keyboard or a map or whatever. Make it in silk and it is indestructable (well almost) and yet very small. http://duo.irational.org/food_for_free/material_maps/silk_map.html
Don't fight for your country, if your country does not fight for you.
The speed of sound happens to be much higher in solids. The more rigid the material, the faster sound will travel through it.
Mic your PC's case so it can respond appropriately when you smack it out of frustration.
Have gnu, will travel.
saw stuff like this years ago. cant find the exact tech demo that i originally saw that used 3 mics for triangulation, but this video is pretty close. even mocked up a rough version (low precision, slow response time, but pretty damn good for an afternoon worth of work and very little experience with arduino) tied to a projector in my shop. customers had a blast with it, thought it was the coolest thing in the world. http://www.youtube.com/watch?v=CxDHiwheK8w&feature=related
This student project from Cornell a couple years ago uses a similar idea: http://people.ece.cornell.edu/land/courses/ece4760/FinalProjects/s2009/gh96_jbw48/gh96_jbw48/index.html
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