If you find 3D printers to be just a little too coldly futuristic, this contraption might be more to your liking. Scientists from Cornell University have created a machine that knits solid 3D objects out of nice old-timey conventional yarn.
The prototype device is made mainly of 3D-printed components, and incorporates a bed of knitting needles arranged in a 6 x 6 block. A motorized knitting head dispenses yarn to any of those needles in sequence, as determined by a program on a computer that’s controlling it.
Each of the needles in turn consists of a 3D-printed symmetrical double hook connected to a brass support tube. Because the front and rear sections of the hook move independently, it’s possible for the device to either knit or purl, depending on which section of the hook picks up the first loop of yarn.
Cornell University
The machine is still relatively slow at this point – and prone to errors such as dropping loops – plus so far it’s limited to creating simple objects such as wrist warmers, pyramids and boxes. That said, its functionality should improve considerably once the technology is scaled up, which would partially involve adding more needles to the knitting block.
Possible future applications of the device include the production of three-dimensional scaffolding-like structures used to support the growth of artificial ligaments or veins. And by knitting such structures instead of printing them, it will be possible to precisely control their thickness and stiffness.
Cornell University
“We establish that not only can it be done, but because of the way we attach the stitch, it will give us access to a lot of flexibility about how we control the material,” says the lead scientist, Prof. François Guimbretière. “The expressiveness is very similar to a 3D printer.”
A paper on the study was presented in September at the ACM Symposium on User Interface Software and Technology in Busan, Korea.
And no, this isn’t the first time we’ve heard about 3D-knitted objects.
Carnegie Mellon University – which collaborated with Cornell on its device – has previously developed software that transforms existing knitting machines into 3D printers, built a dedicated solid-knitting machine, and created robo-knit furniture that transforms from flat to three-dimensional shapes with one pull.
Source: Cornell University
