A camera records the movements of the users; vision-based software tracks their fingers. Images can also be projected in front of the multi-touch screen's users.
Using multitouch input on the one hand and 3D data visualisation on the other, a user now can almost touch the 3D content and seamlessly interact with it. Thus, the Touchtable itself becomes an incredible and unique tool for the presentation and explanation of advanced processes along the value chain of plant engineering and construction: Plant elements are selected by simply touching them. Once selected, these components can be rotated in almost 360 degrees and continuously be zoomed and regarded as close as possible. Never before, one could have such an incredible and phenomenal insight.
However, there is a much older example from the classic 1927 silent film Metropolis, by Fritz Lang. In the film, vast factories and production facilities are controlled from a single "desk."
(Metropolis control "desk")
Using this device, the controller could bring up any factory floor or area, and place a call to the foreman. Various parameters about that area were also presented.
(Metropolis control center detail)
Microsoft has a recently introduced device that is somewhat similar - The DigiDesk. Take a look at the Microsoft DigiDesk prototype in action in the YouTube video below.