build a room

At the core of the Exploratorium's 'Geometry Playground' exhibition is the concept of spatial reasoning: the ability to create a mental model of a space, and to navigate and manipulate it. Build A Room allows visitors to create three-dimensional spaces out of thin air with a "light brush", custom software, and a room-sized canvas.


build a room
Build A Room began as an exhibit about rotational geometry, but visitors found more enjoyment painting with the "light toys" than spinning them around an axis. Taking a cue from visitors, we redesigned the interaction to focus on painting; but we opted to coax the painting activity into the third dimension, encouraging more spatial reasoning than 2D light painting alone.

A "light brush", designed to look similar to a spray can, lets visitors paint with light. A small room, open on two sides, is inscribed with a grid that provides cues for visitors to draw in three dimensions. Opposite the room is a camera that captures the visitor's movements, and a display that shows their three-dimensional painting unfolding in realtime.