'Shoe sole with spikes popping out when walking' is developed, which is inspired by Japanese 'cut paper'

' Kirigami ' is an art from Japan that creates various patterns by cutting folded paper. A joint research team from the University of Massachusetts (MIT) and Harvard University, which was inspired by such paper cutting, has developed 'Shoe soles with spikes when walking'.

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'Kirigami' is a paper art that creates various patterns by folding paper and then cutting it. If you look at the following movie, you can see at a glance what kind of cutting paper is.

KIRIGAMI PAPER ART POP-UP CARD EASY-Tutorial-YouTube


The joint research team of MIT and Harvard University has come up with the idea of cutting paper to create 'shoe soles with spikes when walking'. The real thing of this shoe sole is as follows. A plate with a notch like a snake scale.

The feature of each notch is that it emerges when bent. It is said that the cuts that become three-dimensional when bent are inspired by cut paper.

The sole remains flat when the wearer is standing, but the notch is raised during walking to act as a spike. “It can help prevent falls, especially in older people,” the research team explains.

The research team made prototypes of various shapes such as squares, triangles, curves, and rhombuses, and measured rigidity, accuracy, friction force, etc. on various surfaces such as ice, wood, vinyl floor, artificial grass .. As a result, it turned out that the notch of the diamond was the best as a spike.

In addition, we actually attached this sole to various kinds of shoes such as sneakers and winter boots and conducted an experiment to walk on a friction measuring machine covered with 1 inch (about 2.5 cm) thick ice. However, it has been confirmed that when this shoe sole is attached, the frictional force is improved by 20 to 35%.

The research team is focusing on commercializing this shoe sole, and is considering whether it should be a type that can be attached to the shoe as needed, such as crampons , or an integrated shoe. That. In addition, in the research released this time, the material of the shoe sole was limited to plastic or stainless steel, but the research team said in the future, “The shoe sole itself is based on a polymer like rubber, but the cut part is an iron tip We plan to continue the experiment by combining multiple materials, such as 'Reinforce.'