http://www.thedesignblog.org/entry/wufu-gl...-for-the-blind/

i do wonder how the images resolve into vibrations tho. It cant be high resolution.

I'm guessing it is a fairly simple system like "Both vibrating means there is something in front of you, the more they vibrate the closer it is." Or maybe there are several small things that can vibrate independently to give an idea of what direction and how close things are.