Despite the existence of softer plastics and materials, 3D printers are still primarily designed to create hard, solid objects that don't have much bend or give. But a researcher at Carnegie Mellon University has successfully hacked a machine to create the world's first 3D-printed teddy bear using a technique called felting.
The final result looks like it was knitted by a grandparent, but while wool is the primary ingredient, the hacked 3D printer doesn't work like a knitting machine. Instead, the felting technique involves repeatedly poking the wool with a needle so that its relatively loose fibres get interwoven with the layers beneath it, as demonstrated in this video.
Surprisingly, hacking a 3D printer to felt with wool instead of extruding melted plastic wasn't terribly difficult, as creator Scott E. Hudson explained. And you can even use the same 3D models and software as you would when working with plastic, you just need to take into account wool's tendency to spread out and puff up as it's being laid down.
The process needs to start with a base layer of existing felt, so that the first layer of wool has something to stick to as it's being poked with a needle. But after that, the printer can create layer after layer of felted wool to build up a 3D model that ends up feeling plush and cuddly.
The only limits to how large you can make your teddy bear are the size of your 3D printer's bed, and how much time you have to wait — since the process is even slower than when using extruded plastic. But Hudson's creation is an important step in the evolution of 3D printers, as it demonstrates that eventually they will be able to create objects from almost any material. Even if teddy bears might not be the first thing we'll make when Star Trek's replicators are finally realised. [ACM Digital Library]