Today’s invention is a system intended to make buying drinks in a bar more interesting and less time-consuming.
A group of people would sit at a table with an interactive surface.
When someone wants another drink they type in a pin code and select a drink from a menu which appears beside their glass.
The system knows the exact current position of the glass and authorises one of a number of tubes behind the (unmanned) bar to fire the drink through the air, over the heads of patrons, and into the glass. (Glasses might need to be more like brandy balloons to avoid spillage.)
Given reasonably still air in the room, this could be achieved over distances of perhaps 5m.
Yes, of course some people will move their glasses out of the way and attempt to interpose their mouths.