Wednesday, October 01, 2025

Kirigami parachute suitable for humanitarian missions unveiled

Polytechnique Montréal research project published in Nature

Polytechnique Montréal

image:
Frédérick Gosselin, Danick Lamoureux and David Mélançon with a prototype of their kirigami-patterned plastic parachute.They published their results in the article *Kirigami-inspired parachutes with programmable reconfiguration*, which was published online in *Nature* on October 1st 2025.
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Credit: (Photo credit: LM2)

Kirigami is a technique that modifies the mechanical properties of a sheet of material by making precise folds and cuts to it. Children use it to make snowflakes out of paper, and engineers have used it to create extensible structures, flexible medical devices and deployable spatial structures. However, kirigami techniques have never been applied to parachute production.

The Polytechnique Montréal research team has now changed all that.

A parachute cut from a plastic sheet

Through a groundbreaking project, led by professors David Mélançon and Frédérick Gosselin from Polytechnique Montréal’s Mechanical Engineering Department, a new type of parachute made from a plastic sheet cut in a “closed-loop” kirigami pattern as been developed.

The pattern used gives the sheet of plastic new mechanical properties. In free fall, it assumes the shape of an upside-down bell when any type of weight or object is attached to its centre.

“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.”

The research team believes these characteristics could be useful for purposes ranging from parcel delivery in remote areas to exploration of Mars in outer space. However, in their view, the most likely and practical application in the near future is

humanitarian aid deliveries of water, food and medicine, particularly since the parachute has a very low production cost.

“We made these parachutes by laser cutting, but a simple die-cutting press would also do the trick,” Mélançon says. “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.”

The researchers tested their concept through numerical simulations, wind-tunnel tests, laboratory drops and outdoor drops from a drone. The tests point towards a considerable potential that has yet to be explored.

“The parachute’s behaviour doesn’t change even when the size of the device is augmented,” says Frédérick Gosselin. “This suggests that it could be scaled up for larger applications.”

The Polytechnique Montréal research team is now working on identifying new cutting patterns to endow the parachutes with different and new properties. “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 endeavour that opens up a multitude of possibilities.”

Learn more about this story:

https://www.polymtl.ca/carrefour-actualite/en/news/parachute-polytechnique-montreal-lands-nature

Nature article:

Kirigami-inspired parachutes with programmable reconfiguration

Media kit:

https://polymtl.info/hpcuz

Journal

Nature

DOI

10.1038/s41586-025-09515-9

Method of Research

Experimental study

Subject of Research

Not applicable

Article Title

Kirigami-inspired parachutes with programmable reconfiguration

Article Publication Date

1-Oct-2025

Drones were used to release the parachutes from a height of 60 metres during the outdoor tests.
Credit
David Mélançon

CLaser cutting of a closed-loop kirigami pattern allows a plastic sheet to adopt the shape of an inverted bell.

Credit

Martin Primeau

A laser cutter is used to create a parachute from a sheet of plastic or paper. [VIDEO]

Indoor release of a paper version of the parachute [VIDEO]

Indoor release of a paper version of the kirigami parachute [VIDEO]

Once deployed, the plastic or paper sheet, cut using a kirigami pattern, opens into an inverted bell shape, acting as a parachute when the cargo is attached at its center.

Drones were used to release the parachutes from a height of 60 metres during the outdoor tests.

Credit

David Mélançon

Arnold Schwarzenegger downplays Trump and backs Vatican initiative to 'terminate' global warming

By NICOLE WINFIELD with AP

Published on 01/10/2025 - EURONEWS

His Schwarzenegger Climate Initiative is one of the backers of the Vatican conference, which is being held at the Holy See’s newly inaugurated environmental educational centre.

Arnold Schwarzenegger downplayed the Trump administration’s climate scepticism on Tuesday and threw his weight behind the Vatican’s environmental initiative, saying individual choice, local regulations and the Catholic Church's moral leadership were far more important to “terminate” global warming.

Schwarzenegger was at the Vatican to headline a three-day climate conference marking the 10th anniversary of Pope Francis’s landmark 2015 environmental encyclical, Laudato Si (Praised Be).

The document, one of Francis' main legacies, cast saving God’s creation as an urgent moral imperative and launched a broad, grassroots movement that Pope Leo XIV has fully embraced and made his own.

Schwarzenegger, the former Republican governor of California, has devoted time to environmental causes since leaving political office in 2011.

From left, Tuvalu's Climate Minister Maina Talia, Laudato Si' Executive Director Lorna Gold, Cardinal Jaime Spengler, Arnold Schwarzenegger, and sister Alessandra Smerilli.

His Schwarzenegger Climate Initiative is one of the backers of the Vatican conference, which is being held at the Holy See’s newly inaugurated environmental educational centre in Castel Gandolfo, south of Rome.

'An easy way out'

At a news conference, Schwarzenegger was asked about President Donald Trump’s recent comments to the UN General Assembly, where he falsely said that climate change was a "con job".

Trump has long been a critic of climate science and policies aimed at helping the world transition to green energies like wind and solar. His administration has rolled back landmark regulations, withdrawn climate project funding and instead bolstered support for oil and gas production in the name of an “American energy dominance” agenda.

“Don’t use the federal government as an excuse,” Schwarzenegger told the Vatican briefing. “It’s an easy way out.”

He recalled his legal battles with the Bush administration over California’s environmental regulations when he was governor, and a particular victory where “we said ‘Hasta la vista, baby,’” Schwarzenegger said, quoting his famous line from “Terminator 2.”

Schwarzenegger said far more important were individual choices about turning off lights when you leave a room and state policies promoting solar power.

With its 1.4 billion people, 400,000 priests, the Catholic Church also has a critical mass of people who can back environmental initiatives, he said.

Island communities press for “all hands on deck” response to climate crisis

A new, first-of-its-kind survey sheds light on public opinion about climate change in the world’s small island states

University of California - Santa Barbara

Despite being among the most climate vulnerable regions in the world, public opinion from small island states and territories across the South Pacific, Indian Ocean and Caribbean has long been absent from the global discussions of the climate crisis. These countries face disproportionate climate impacts — from sea-level rise to intensifying storms to fresh water contamination, increasing diseases and other health risks — even though they bear virtually no responsibility for the climate crisis.

A new study published in the Proceedings of the National Academy of Sciences fills this gap. Led by a team of UC Santa Barbara researchers in partnership with scholars at Stanford University, University of Pennsylvania, UC San Diego and UCLA, it represents the first global climate survey of these regions. The study found that there is near-universal acceptance of human-caused climate change, high levels of concern about climate-linked environmental threats, and that small-island respondents support an “all hands on deck” approach to addressing the climate crisis.

“We began this work after we discovered that 30 countries in the world had never been included in a global climate survey — and that these were the countries at the frontlines of climate impacts,” said Matto Mildenberger, an associate professor of political science at UCSB and the lead author on the paper. “This has meant that voices from the most climate vulnerable countries and territories in the world have been missing from opinion research.”

This lack of opinion research means that the beliefs and preferences of communities across small island countries and territories have not been accounted for in global climate policy development.

“Our research arrives at a critical moment as the international community seeks to redress the impacts of climate change on the world’s most climate-exposed societies,” added co-author Paasha Mahdavi, an associate professor of political science at UCSB. “We directly measure the attitudes and preferences of individuals in small island states regarding whom they see as responsible for solving climate change.”

Between June and July 2022, the research team led a Facebook advertising campaign in 55 small island states and territories that directed respondents to a survey — delivered in the most common language of the area — that asked their opinion on climate change. Survey participants were asked about their experiences with extreme weather, attitude around climate change, opinion on climate adaptation policies, as well as their perceptions on global climate politics, displacement and migration, and how they would assign responsibility for addressing the climate crisis.

Researchers found that there are very high levels of belief in human-caused climate change, ranging from a low of 89% in Anguilla to 100% in Marshall Islands, Turks and Caicos. “Not only do residents of small-island countries face some of the highest vulnerability to climate change around the world, they also have among the highest belief in climate change and level of concern that we’ve ever observed,” said Gabriel De Roche, a postdoctoral fellow at UCSB and a co-author on the paper. “We find very high levels of concern not just for their own neighbors and countries, but for people the world over.”

Large majorities in every country or territory were also worried about their personal vulnerability to climate impacts, including extreme weather, sea-level rise, coastal erosion and, to a lesser extent, drinking water contamination. Additionally, climate-vulnerable residents perceive that residents of rich countries will also be impacted by climate change, seeing the problem as universal and severe for countries other than their own.

“Interestingly, while many residents in places like the United States view climate change as primarily affecting other countries, we found that residents of small island states and territories view impacts of the climate crisis as a global phenomenon,” said Mildenberger. “Respondents indicated that they view climate impacts as proximate for themselves as well as for distant communities and more developed countries.”

Critically, the study found that respondents generally favor an “all hands on deck” approach to the climate crisis, with responsibility for solving climate change falling on countries who are historic or current major sources of climate pollution, as well as former colonial powers and home-country governments. This finding is important as global discussions around how to assign responsibility for addressing the climate crisis increase.

“A July 2025 ruling by the International Court of Justice — the highest court of the United Nations — has for the first time recognized that people whose lives are upended by climate change may be entitled to ‘climate reparations’ from large emitters like the United States and China,” said Mahdavi. “Our findings paint a nuanced and complex picture that reveals grassroots belief in responsibility not just for large emitters, but also smaller-emitting colonial powers like Spain and the Netherlands, as well as fossil fuel producers like Saudi Arabia. We see these nuances as an important empirical component for policy discussions moving forward in light of the ICJ ruling.”

Their findings, the researchers assert, indicate that communities in small island states and territories similarly favor an “all hands on deck” approach — supporting global climate action, as well as efforts from their local governments — given the urgency of the climate crisis.

“Our research finds an urgent demand for ambitious climate action from residents of small island states and territories,” said De Roche. “This population, among the most affected by climate change’s negative impacts, is calling for all hands on deck action on climate adaptation and resilience. We see a clear opportunity for leaders from these small island states to push for ambitious policy on climate adaptation and resilience by large current polluters, former colonial powers, and within their own governments.”