Idea
The idea was to create a coffee table with a large led matrix, and corresponding proximity sensors. The sensors allow you to have a cool indicator of where objects on the table are or play fun games like pong or airhockey. This is a project I started for fun and decided to make modular and customizable to fit any potential table size.
Controller
The controller board uses a STM32F4 and an analog multiplexer to evaluate all sensor data and control the leds.
Panels
The table is built using 10cm x 10cm pcbs, which include a 6x3 led matrix and a 3x3 sensor arrangement. The proximity sensors are made up of a simple infrared LED and infrared photoresistor.
From cardboard prototype to a first pcb design:
A proximity test using a single panel:
An LED rainbow test using cardboard panels: