工学：切り紙模様が安定したパラシュートを生む

Parachute designs inspired by kirigami — the Japanese art of paper cutting to produce 3D designs — are shown to be stable and fall close to their target, according to research published in Nature. These findings could simplify parachute manufacturing, reduce costs, and improve accuracy for applications such as humanitarian airdrops.

Parachutes are expensive to make, complex to assemble, and often drift far from their intended landing point. David Melancon and colleagues show that parachute design can be simplified by using kirigami-inspired techniques. Laser cutting slits into a disc resulted in structures that open into stable shapes during flight. The authors combined wind tunnel experiments, free-fall tests, and numerical simulations to design and evaluate kirigami parachutes, with designs taking inspiration from wind-dispersal seeds. They identified specific slit patterns that produce shapes that are stable and do not drift off course when falling. A large-scale prototype successfully delivered a water bottle to a target from a drone at a height of 60 metres. The designs show scalability and adaptability to different environmental conditions.

The simple cutting techniques used to make the parachutes may reduce cost and complexity compared with conventional designs, which, together with the accuracy of the parachutes, could make them suitable for the delivery of humanitarian aid, the authors conclude.