Mixed Reality Tabletop
by Jonathan Deutsch
The projection map table was basically a large touch screen table which allowed people to manipulate a globe-like map by touch, zooming in and out and overlaying different satellite and topographical data sets.
It seems that Northrup Grumman put together an interactive tabletop for military cartography and simulations. There’s a pretty cool demo video on their site.
This reminded me of my research at Purdue: the Mixed Reality Tabletop (MRT for short). The main difference between the two setups is that the Northrup Grumman table uses touch sensitivy on the table itself, wheras we opted to used a camera mounted overhead and analyzed the video to detect actions. This meant we had to worry about lighting conditions, shadows, and camera calibrarion. Our system was really designed to be a collaborative medium where two people could share the same tabletop, so the camera was a natural choice to use for such purposes. I think the videos on our site show that the image detection method can work well and allow users to perform advanced operations such as drag-and-drop of virtual objects (due to Dan Belkins’ great work). Of course, the other real advantages of MRT is that it costs 100 times less than the Northrup Grumman system, and you can play games such as Networked Tic-Tac-Toe and Pong on ours (my work!).