Parachutes rarely get the credit they deserve. They transform deadly freefall into a gentle descent, saving lives in war zones, rescue missions, and even humanitarian aid drops. But they come with a flaw: once released, they’re at the mercy of the wind. A carefully aimed package of medicine can easily drift far off target.
Now, researchers from Polytechnique Montréal in Canada and École Polytechnique in France have come up with a clever twist: making parachutes more accurate by cutting them. Inspired by kirigami (the Japanese art of paper cutting) they’ve created lightweight, cheap parachutes that fall with remarkable precision.
Solving the Parachute Problem
The earliest evidence for the true parachute dates back to the Renaissance period. Leonardo da Vinci made important contributions to the design of parachutes, and by the 18th century, modern-type parachutes were already used. Kirigami is even older, being documented since the 7th century AD. Children use it to make snowflakes out of paper, but recently, engineers have used it to create extensible structures, flexible medical devices, and deployable spatial structures. But kirigami and parachutes don’t seem like they’d do well together.
Conventional parachutes work by catching air, so slicing holes into them sounds like sabotage. But instead of altering a parachute canopy, the researchers started with a simple disc of Mylar and experimented with cut patterns.
Their central challenge was to overcome the inherent instability of a falling disc. If you’ve ever dropped a frisbee or a piece of paper, you’ve probably seen this happen: it flutters, tumbles, and drifts unpredictably. To understand how to control this chaos, the team started by laser-cutting three different types of discs from thin Mylar sheets and dropping them from a height of 1.8 meters, each with a small 4.5-gram weight attached to its center.
A plain disc, or one densely cut with concentric slits, tumbled unpredictably, just like a frisbee dropped midair. But another design, with a simpler kirigami pattern, transformed into an upside-down bell shape when weighted. Unlike its chaotic cousins, this disc stabilized instantly and dropped straight down.
“One advantage of this parachute is that it quickly stabilizes and doesn’t pitch, regardless of the release angle,” says Mélançon, co-author of the article. And unlike conventional parachutes, it follows a strict ballistic descent trajectory.
Putting It to the Test
After landing on a promising design, the team put their kirigami parachutes through a series of increasingly realistic tests. They tested the design in a wind tunnel, in the lab, and with outdoor drops from a drone. In all instances, the kirigami parachute behaved remarkably well, comparable to a “regular” parachute. Furthermore, the behavior didn’t seem to be size-dependent.
“The parachute’s behavior doesn’t change even when the size of the device is augmented,” says Frédérick Gosselin, one of the study authors. “This suggests that it could be scaled up for larger applications.”
The real test, however, was precision. They dropped parachutes based on the unstable Design A, the stable Design B, and a small conventional parachute from a height of 16.6 meters (about 54 feet) onto a target below. To make it even more challenging, they released them from different initial angles: perfectly flat (0°), tilted (45°), and even completely on its side (90°).
The stable Design B parachutes landed in a tight cluster, almost all of them within a meter of the bullseye, regardless of the release angle. The kirigami pattern didn’t just prevent tumbling; it ensured a landing of unprecedented accuracy.
For the grand finale, the team scaled up their concept to prove it could handle a meaningful payload. They fabricated a half-meter diameter parachute, attached a water bottle, and mounted it to a drone. The drone flew to an altitude of 60 meters (nearly 200 feet) and released its cargo. The kirigami parachute stabilized the water bottle as it descended, although the speed was still higher than it would have been with a regular parachute.
Why This Matters
This technology could be useful for purposes ranging from parcel delivery to exploration of other planets. However, the researchers say the most likely application they’re looking at is humanitarian aid: deliveries of water, food, and medicine. The reason is that the parachute is extremely cheap to make. Instead of the complex sewing and assembly required for traditional parachutes, these can be mass-produced by simply laser-cutting or die-cutting a pattern onto a roll of plastic sheeting.
“We made these parachutes by laser cutting, but a simple die-cutting press would also do the trick,” David Mélançon, one of the co-authors, explains. “What’s more, the parachute is seamless and is attached to the payload by a single suspension line, making it easy to use and to deploy.”
But the researchers say this is just the beginning. The future for this technology is wide open. The design could be optimized further by covering the kirigami slits with a soft, stretchable membrane to increase drag and slow the descent even more. By exploring more complex, asymmetric kirigami patterns, it might even be possible to program the parachute’s entire trajectory, guiding it along a specific path to its target.
“We want to change the patterns in order to go even further: the parachutes could descend in a spiral, for example, or glide before dropping,” says Mélançon. “We would also like to be able to vary the trajectory of descent depending on the payload, so the cargo could be sorted as the parachutes come down to Earth. This is a whole new design endeavor that opens up a multitude of possibilities.”
Parachutes have remained largely unchanged for centuries. They may soon get a revamp.
The study was published in Nature.
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