These parachutes unfurl thanks to the Japanese art of kirigami

These innovative parachutes may appear to have a multitude of holes, yet they are exceptionally precise in their performance.

Drawing inspiration from the traditional Japanese craft of kirigami, which involves intricate paper cutting, researchers have developed parachutes that automatically deploy upon being dropped. Unlike conventional parachutes, these unique designs descend directly downward regardless of their initial orientation, thus making their trajectory more predictable.

The design features a thin Mylar disk, intricately perforated with a series of concentric slits, which unfolds into a beautiful lattice-like structure, resembling a vase, as the cargo it carries descends. The force of the rushing air pulls the parachute open, creating a drag effect that effectively slows down the payload’s descent.

In laboratory simulations, when compared to traditional parachutes or uncut disks, the kirigami parachutes landed more precisely on target, as reported by the research team in the October 2 issue of Nature. “I can toss this thing in any direction. It will always orient itself and descend straight down,” explains mechanical engineer David Mélançon from Polytechnique Montreal, showcasing one of the team’s kirigami devices. The ease of construction and deployment of these parachutes is also highlighted by Mélançon, noting that they eliminate the need for sewing and folding, which is often required for standard fabric parachutes.

Interestingly, because they are designed with numerous perforations, the kirigami parachutes generate less drag compared to similarly sized traditional models. To safely support a human, a kirigami parachute would need to have a radius of about 100 meters—almost equivalent to the length of a football field—to prevent a hazardous landing.

For simpler experiments, the researchers conducted a drop test using a 1-kilogram water bottle from a drone flying at an altitude of 60 meters, deploying a kirigami parachute measuring 0.5 meters in diameter. The drop resulted in a falling speed of approximately 14 meters per second; in contrast, a water bottle dropped without a parachute would have hit speeds up to 34 meters per second.

The potential applications for these parachutes include delivering humanitarian aid or facilitating drone package drop-offs, suggests Mélançon. The research team is also exploring the use of eco-friendly materials such as cardboard and various design alterations. For instance, the disks could be modified to mimic the swirling fall of winged maple seeds, which would be advantageous for space missions on other planets, allowing instruments to capture panoramic images as they descend through extraterrestrial atmospheres.