Overview
"The Gardeners' Fresco" is a large-scale interactive installation where the public collectively plants a vast virtual garden. Participants grab a "seed bomb" — a wireless, hand-held object — aim at the spot on the digital fresco where they wish to plant, and press a button to send their seed. They then watch their unique plant grow and populate the ever-evolving artwork. The experience is designed to be simple, poetic and magical, hiding the underlying technology to create a seamless, enchanting interaction for all ages.
Technical details
The project required mastering a new technology stack centered on real-time 3D localization using Ultra-Wideband (UWB), chosen for its precision, reliability in interference-prone environments and low power draw. The system is built on a network of custom electronic modules: 5 fixed "anchors" around the screen and mobile "trackers" embedded in each seed bomb (Makerfabs ESP32-S3 + STM32-driven DW-3000 UWB modules). The firmware was hand-written in C; much of the work went into taming radio waves — interference, frame filtering, correcting measurement imprecision. Each bomb measures its distance to all 5 anchors 20 times per second and transmits button state over UWB, WiFi-free, for several days of battery life. A Python application is the brain: serial data ingestion, a Flask/HTML calibration interface, real-time 3D triangulation then orthogonal projection onto the screen plane (an X,Y cursor at 20 Hz). Measurements, smoothed with Kalman and One-Euro filters, are packaged as JSON and sent over OSC to Unity, which renders the graphics and triggers the immersive sound design — hiding all the complexity to preserve only the wonder.