Cool build, the author took a bar caddy, a bunch of 3D printed parts, and an Raspberry Pi (oh and some motors and controller board) and build an 4 tank mixer with it all. The RPi is the controller and the interface for folks to use the mixer. Me, I think I’ll stick to mixing my own drinks.
http://www.instructables.com/id/Beverage-Appliance-with-Web-Interface/