OnderDruk

OnderDruk ("under pressure") is an interactive installation developed for the Huis van Kina, a museum in Ghent, about how stones are formed. Visitors get a challenge on screen, such as "Make this stone: Pyrite", and use a physical control panel to combine the right amounts of water, fire, time, temperature and pressure. When they get it right, the screen shows the stone and its properties, and the matching compartment in a tower of real stones lights up.

My Role

I built most of the technical chain behind the installation, from the buttons to the screen:

Arduino firmware. I programmed the Arduino that reads the buttons and dials on the control panel, sends every change to the Raspberry Pi over a serial connection, and switches the lights in the stone tower.
Backend. My Node.js server on the Pi parses the Arduino's messages into the current state of the game and compares it with a dataset of stones, each defined by its combination of water, fire, time, temperature and pressure. When a stone matches, it sends a command back to the Arduino to light up that stone's compartment.
Frontend logic. On the screen, I connected the React interface to the server over a WebSocket, so every change on the control panel immediately updates what visitors see.

Began the walls of "the Great Hall" — Behind the scenes images of the hardware testing

Finalized my first building and tower — Behind the scenes images of the hardware testing

Built to Run on Its Own

A museum installation has to work every day without a developer nearby. On the Raspberry Pi, the server starts automatically as a system service, and the screen only opens in kiosk mode once the server is running. When the screen connects, the server immediately sends the current state, so the display always shows the right information, even after a restart.

Testing the control panel and the stone tower.

The Challenge

An interactive installation only works if it feels immediate: when a visitor turns a dial, the screen and the tower have to react straight away. The main challenge was keeping the chain from control panel to Arduino, server, screen and lights fast and reliable enough to maintain that feeling.

_Built with Tristan De Ridder, Arda Sager and Jan Skrzynski for Digital Product Studio. Interface design by Jan Skrzynski.