Create an LED Coffee Table That Reacts to Whatever's Placed On It

While coffee tables area great for holding coffee, magazines, food, and assorted knickknacks, this was apparently not good enough for hacking duo "Ty and Gig Builds." Instead of constructing a mere passive table, they enhanced their java platform with an array of 96 addressable LEDs. These can not only light up in various set patterns, but also react to what’s placed on top thanks to IR emitters and receivers beneath the furniture's see-through surface.

Although the concept is easy enough to grasp, the device’s sensing arrangement involves seven rows and 11 columns of two IR emitters and two IR receivers each, meaning 154 of each of these components – or 308 in total – had to be soldered into place. Holes in the light/sensor subplate underneath also had to be marked and cut, which as shown in the video below wasn’t a trivial job either. The results are a lot of loose wires hidden underneath, which are connected to a number of custom shift register/multiplexer boards for proximity detection.

An Arduino Mega clone, in turn, is used for control of the overall setup, and the LEDs themselves would seem to be the easiest part of the build. More info is available in the project's write-up as well as this imgur set, and the code is on GitHub if you’d to examine it.