Shaper is a prototype device that uses a three-axis computer numerical control (CNC) machine to interactively dispense expanding polyurethane foam material. The user controls the device via a translucent touch screen to create physical artifacts with sketch-like gestures. Shaper challenges the conventional process of digital fabrication by allowing direct interactive control.
The translucent touch surface is situated above the fabrication area, so that users can directly see the physical output. The gesture interface is projected onto the rear of the touch surface and a depth map is stored to allow multiple layers to be built up into three-dimensional form. The software detects when sketch lines intersect and raises the dispenser head to the appropriate height; material can then be built up layer by layer.
Shaper uses several open source toolkits and applications to control and drive the CNC machine. The interface is developed using the openFrameworks toolkit and gesture commands are sent from there to a python bridge. The python code interprets these commands into standard G-code and drives the CNC machine using the EMC2 application.
The polyurethane foam dries into a lightweight and smooth material. Illustrated here are the type of physical ‘pixels’ that can be created with expanding foam. We chose expanding polyurethane foam to enable quick fabrication. Unlike other additive 3D printing processes, foam quickly expands to a substantial volume.
Created by: Cheng Xu & Karl D.D. Willis
Research Paper: Interactive Fabrication: New Interfaces for Digital Fabrication
Funded By: Fine Foundation Grant

