Posted on 07/12/2018 4:23:05 PM PDT by Diana in Wisconsin
A new theory could help engineers to create materials for use as smart textiles, artificial tissue and even the aerodynamic contours in jet turbines by knitting them.
The oldest known example of knitting is from Egypt over a thousand years ago, yet until now scientists did not fully understand how a non-stretchy yarn could be entangled into such a stretchy fabric.
The new study, published in the journal Physical Review X, boils knitwear properties down to three parameters yarn bendiness, the length of yarn, and the number of crossing points in each stitch.
The simplicity of the model will enable scientists to begin designing knitted materials with custom shapes and properties, says lead author of the paper, Samuel Poincloux from the Ecole Normale Superiore in Paris, France.
If you understand it well, you can tune your structure to have the properties that you want, he says.
Poinclouxs analysis found that the primary source of a knitted fabrics stretchiness came from the loop created as the yarn in one row of stitches weaves through the row above and the row below. When the fabric is pulled, it is able to stretch because the loops become distorted. The energy to do so comes from bending the yarn.
The way the loop can stretch is also limited by the number of times the yarn crosses with neighbouring stitches, and the total length of the yarn in the fabric.
The analysis found yarn bendiness, crossing points and total yarn length were enough parameters to accurately deduce the properties of the material. Poincloux says this should provide a theoretical basis for material designers looking a much more efficient way to create new materials, compared to the current trial and error methods used in industry.
When I discussed with industry they said they do not have a good fundamental bottom-up design model, Poincloux explains.
The work originated when Pounclouxs PhD supervisor, Frédérick Lechenault, watched his wife knit clothes for their unborn child. Lechenault marvelled at the way she could create three-dimensional shapes, such as booties, that would return to their shape even after being stretched significantly.
Lechenault was at the time studying origami, investigating how structure created by folds could alter the properties of a paper object. The one-dimensional nature of yarn suggested the challenge would not be too complex, so he set Poincloux to work analysing knitting stitches.
To get his head around the task Poincloux visited the knitting workshop at the École Nationale Supérieure des Arts Décoratifs across the road from his lab, and learned some stitches.
Discussing with artists and designers is very interesting, they have a different point of view and a very deep knowledge of what you can do, which can inspire you to design new stuff, Poincloux says.
Knits have interesting three-dimensional shapes that appear naturally by changing the stitch pattern. The composite industry can use knitting because its quite stretchable and they can fit it to a complex shape, for example in an aeroplane engine turbine.
Oh, this is so much fun. My favorite topic - knitting.
There is research out there that lifelong knitters live longer than the rest of you people.
...you get to stab things with sharp needles over and over and over! and no one gets hurt!
Try needle felting, and you can go in three dimensions.
But you may draw some blood until you get the technique down. Still relaxing fun.
What else do The Saints have to do besides marching in?
Sounds Kooky....
#11 There is the article on the rightside of the page:
Coming clean: the physics of doing the laundry
https://cosmosmagazine.com/physics/coming-clean-the-physics-of-doing-the-laundry
Maths and Knitting: Fibonacci Day
What happens when mathematical equations meet beautiful knitting patterns? Discover mesmerizing projects designed using Fibonacci sequences!
The Fibonacci spiral, also known as the Golden Spiral, is a numerical pattern that was first identified in the Western world by Italian mathematician Fibonacci.
The sequencing sees numbers, starting from 0 1, advance with the next number being the sum of the last two. For instance, [0 + 1] 1, [1 + 1] 2, [1 + 2] 3, [2 + 3] 5 and so on
https://blog.loveknitting.com/knitting-with-fibonacci-math/
I’ve used his formula to make some interesting pieces through the years. Math & Crafting = FUN! :)
LOL!
LOL!
That's the difference between science and engineering, and craft. The scientist will provide a theoretical explanation of what the craftsman knows but does not fully understand. The engineer will take that theory and expand the technique in ways the craftsman would never have dreamed.
Love this ... adding it to my cool knitting pics.
My mom never had to deal with obama
Note: this topic is from . Thanks Diana in Wisconsin. Oh, and to hell with the Ravelry website.
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