Graffiti sand printer

Interesting robot printer combo that prints out words with sand and the medium.   This was an article on it from a while back, but I never got a chance to look into it til now.  Cool looking bot, but little to know info on how to build one.

http://gizmodo.com/if-a-graffiti-printer-writes-with-sand-is-it-still-real-1512594866?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+gizmodo%2Ffull+%28Gizmodo%29