Giant Etch-A-Sketch

Interaction Study

Project Overview

This coffee table sized Etch A Sketch was an exploration into how physical interactions with products can change with scale. We reimagined the original mechanism using a CNC gantry and a magnetized marble rolling on sand. This was a group project for a class about designing product interactions, I lead the team through the technical execution of this prototype.

Design

There were several components that needed to interface in order to this project possible: the CNC gantry that drags the marble around the board, the knobs which read the inputs and sent commands to move the marble, and the sweeping mechanism that erases the drawing, and the outer curved housing made of plywood.

Mechanisms

The gantry system was controlled by an Arduino Uno with a CNC shield running GRBL control software. The gantry received G-Code commands from a second Arduino which read the encoder positions of the knobs to determine what direction to move the marble.

The clearing mechanism consists of a wide brush attached to a timing belt that sweeps the brush across the sand. The motion is controlled by a third Arduino that is reading an accelerometer to detect a shake.