Blowable User Interface
I just got back from presenting a paper at UIST, a conference that I would describe as a forum for innovative sexy user interfaces. One of the more original talks I attended was by a Georgia Tech student who managed to create a blowable interface on a standard laptop. He takes an ordinary laptop (with no hardware add-ons), blows on the screen, and the laptop identifies where he blew. Seems impossible?
How it works: when the screen is blown, it creates a bit of sound that the microphone picks up, Using a Fast Fourier Transform to create a vector of amplitudes and phase shifts, the system then matches a “blow” (as opposed to a click) with pre-classified vectors using k-nearest neighbor. The best vector match is used to determine where on the screen the user was blowing. During evaluation on a laptop, it was 100% accurate on a 3X3 grid, 95% accurate on a 4X4 grid, and quickly degraded after that. This is pretty good considering you’re blowing on a laptop screen.
One application of this would be birthday cards sent over email, where the recipient could blow out the candles. Or, even an electronic harmonica if the accuracy were improved.
Patel told me on a shuttle ride that he discovered this by accident one day while trying to blow dust off his screen with his sound recorder on.
Given that few people would actually perform the embarrassing act of blowing on their laptop while people were around, I’d give this 10/10 for originality and 4/10 for actual usefulness.
Patel, S & Abowd, G. (2007). BLUI: Low-cost Localized Blowable User Interfaces. Proceedings from UIST ’07: ACM Symposium on User interface Software and Technology, 217 – 220. [PDF]