3D printed Disney Teddy Bear. Source: Disney Interactive
3D printed Disney Teddy Bear. Source: Disney Interactive

Disney Research and Scott Hudson, from Carnegie Mellon’s Human-Computer Interaction Institute, have developed a 3D printer that uses wool and yarn to create fabric objects, such as teddy bears.

The 3D printer is a mix between a 3D printer and a sewing machine. The machine creates items from felt, similar to hand-knitted products. The 3D printer uses a CAD file, and prints with yarn.

“I really see this material being used for things that are held close. We're really extending the set of materials available for 3D printing and opening up new possibilities for what can be manufactured,” said Hudson.

A felting needle pierces the yarn and drags fibers into the layer below in order to bond the layers together. The result is not as strong as traditionally-made fabrics, and if the felt products are attached to a harder object, nylon mesh fabric must be used during the printing process for reinforcement so that the material doesn’t rip away.

In his research paper called “Printing Teddy Bears: A Technique for 3D Printing of Soft Interactive Objects,” Hudson writes, “the printer 'allows the substantial advantages of additive manufacturing techniques (including rapid turn-around prototyping of physical objects and support for high levels of customization and configuration) to be employed with a new class of material.”

Hudson continues, “This material is a form of loose felt formed when fibers from an incoming feed of yarn are entangled with the fibers in layers below it. The resulting objects recreate the geometric forms specified in the solid models which specify them, but are soft and flexible – somewhat reminiscent in character to hand knitted materials. This extends 3D printing from typically hard and precise forms into a new set of forms which embody a different aesthetic of soft and imprecise objects, and provides a new capability for researchers to explore the use of this class of materials in interactive devices.”

Currently, the printer only uses one material, but researchers are looking to combine different types of materials in one printer.

“A number of researchers are looking at mixed materials in 3D printing. That's one of the most interesting challenges now,” Hudson explained.