Imagine an egg fall to the ground from a counter-height spot: at the moment of landing, compression, the pushing force, cracks the eggshell open. To rescue the egg, one could have placed a trunk of jello or a thick rug on the floor, which creates an elastic or dampening layer that reduces the stress on the egg upon impact.
But instead of creating a bouncy or crushioning surface, what if there's a different way to protect the egg? Say a protective shield that turns the crushing stress into tension, the pulling force?
This seemingly impossible subject is the focus of a team of U.S. researchers, who drew inspiration from origami the ancient art of paper-folding. They built a structural unit called Triangulated Cylindrical Origamis (TCOs) with several creases (a crease is a line caused by folding). And then they compiled many of these units into a tube-like protective module, creating a metamaterial with a unique mechanical property - it turns initial compressive stress upon impact into tension.
Metamaterials are a class of innovative, specially structured materials with reality-bending qualities, such as super lightweight, light-shielding, total sound-absorbing, or ultra-elastic. They are capable of these incredible feats, not because of their makeup substance or ingredients, but due to their unique, often repeating inner structure.
The group of scientists is hoping to apply this counterintuitive mechanism on aerocrafts and rockets, to create an efficient and reusable impact mitigating system for their landing.
They published their study recently, in a paper in the journal Science Advances.
Source: Seeker via Youtube