What is robotic 3D-printing extrusion, and what is it for?

Biomimetics—the science that finds inspiration in nature to engineer human-centered solutions—has led to the development of a robotics-integrated 3D-printing device that produces self-supporting forms in space. Architectural student Ji Shi and his collaborators in Shanghai have developed what he calls Robotic 6-Axis 3D Printing, or robotic extrusion. The material and fabrication method mimics the micro-structure and production of spider silk. I'm not sure of the applications that may result, but the process is certainly mesmerizing to watch (see the video at the end of this article).

Key to the extrusion process is a Kuka six-axis robot with end effectors to which three mobile print heads are attached arrayed around a fourth fixed print head. Each print head incorporates a heater that maintains a precise temperature to permit extrusion of the ABS/PLA material. As the material strands exit the print head, they are blasted with compressed air so that they harden.

The four material delivery systems are driven by individual servo motors, explains Shi on the Behance website, and an additional motor rotates the central turn-plate. Printing and rotation speeds can be adjusted to achieve specific structures.

So, that's what robotic extrusion is all about. As to what it might be used for, Shi suggests, somewhat obliquely, that it provides designers with a "digital method to eliminate the line between designing and fabricating." It would liberate architects from conventional drawings and construction notes, for example, by allowing them to fabricate their work quickly and precisely, he adds.

The technology was developed during a workshop at the College of Architecture and Urban Planning in Shanghai. Diagrams, exploded views of the system and the aforementioned video can be viewed on www.behance.net. To watch the video, you can also click on the image below, which will take you to the Vimeo page.