These parachutes unfurl thanks to the Japanese art of kirigami

These parachutes may be full of holes, but they really hit the mark.

Inspired by the Japanese art of kirigami, or paper cutting, scientists made parachutes that open automatically when dropped. And unlike traditional parachutes, they fall straight down, no matter which way they were originally facing, making their falls more predictable.

A thin disk of Mylar, perforated with a series of concentric slits, expands into an elegant latticework vase as its attached cargo falls. Pulled open by the rush of air, the shape slows the payload’s fall by producing drag.

In laboratory tests, compared with traditional parachutes or uncut disks, the kirigami parachutes fell closer to an intended target, the researchers report in the Oct. 2 Nature. “I can toss this thing any way I want. It will always realign and then fall straight down,” says mechanical engineer David Mélançon of Polytechnique Montreal, casually slinging one of the team’s disks. The parachutes would also be simple to construct and deploy, Mélançon says, whereas traditional fabric parachutes require sewing and folding.

Because they’re full of holes, the parachutes produce less drag than similarly sized traditional parachutes. A human dangling from one of the kirigami parachutes would need one with a radius of about 100 meters — nearly the length of a football field — to keep from crash-landing.

As a simpler test, the researchers dropped a 1 kilogram water bottle from a drone flying at a height of 60 meters, using a kirigami parachute 0.5 meters in diameter. The bottle reached a speed of about 14 meters per second; a bottle without a parachute would’ve topped out at about 34 meters per second.

The parachutes could be used for humanitarian aid drops or drone package deliveries, Mélançon suggests. The team is also considering using biodegradable materials like cardboard and other design tweaks. For example, the disks could be cut so that they fall with the whirling motion of winged maple seeds. That could come in handy on space missions to other planets, to allow a camera to take photos of the vistas from all angles as it descends through an alien atmosphere.