This project was a pro bono piece for a friend of mine who was working on a gallery exhibition for Mind in Haringey, a mental health charity. The outline was to display a poetry reading, which included seven different video streams and one audio stream.
In order to achieve this, we used seven Raspberry Pis to each output one of the video files, of which one was connected to an amplifier for the audio output.
We chose to power them from a (slightly modified) ATX PSU from an old PC as these parts are relatively easy to come by and provide more than enough power.
The main challenge was to control them all at the same time, and since we were working to a budget, we decided not to use network equipment.
Also the display had to be activated by someone with no technical background.
We decided to use a remote control from one of the TV sets with the help of an Arduino.
Connecting the serial output from an Arduino to the serial input of the Raspberry Pis allowed us to write a program for the Arduino that sends commands to each Pi simultaneously based on a button press from the remote control.
The piece was well received at the exhibition.