Multi Touch Floor

Laser Range Scanners, Embedded Linux, PhidgetSBC, OpenCV

August 2010

In Ars Electronica's DeepSpace, I built a system with laser range finders that effectively makes the 16x9 meter floor "multi-touch." More precisely, it senses blobs of contact with the floor at 40 hertz, as long as there aren't too many blobs. The system uses Hokuyo Laser Range Finders which measure distance with 1/4 degree resolution in a plane. Mounted around the floor and aimed inward, their combined output provide the effect of a "touch" sensitive floor, assuming there are not too many objects in the scene, which will make contact blobs mathematically indeterminate. I fleshed out a rough concept given to me, and wrote all the software to track and forward blobs to applications running in the environment.