Brian Trease was a high school exchange student in Japan, twenty years ago. It was there that he was introduced to the art of paper folding. “I’d be folding subway ticket stubs, baseball game lineups; there’s a picture of me in McDonald’s in the city of Kobe holding a big origami crane that I had just folded [out of a hamburger wrapper],” he recalls. “Now it’s come full circle – I’m doing this as my career.”
Now a mechanical engineer at NASA’s Jet Propulsion Laboratory, Trease works on solving one of NASA’s biggest challenges: how to transport and deploy bulky objects as compactly and lightly as possible. NASA began exploring ways to launch and deploy ever larger solar panels without the panels taking up more room and cargo weight. As it turned out, Trease’s childhood hobby proved to be a promising way to accomplish that.
Working with students and staff at Brigham Young University, as well as Robert Lang who is an origami master, the engineers at the Jet Propulsion Laboratory have concocted a preliminary prototype for a 1cm-thick solar array that would be able to expand from 8.9 feet in diameter to 82 feet. The foldable material uses a technique called ‘hannaflex,’ which looks like a flower when folded up and unfolds into a flat, circular form. “This is just begging to be deployed with centrifugal force,” Trease said. “We could have it on spacecraft where we just spin it and that force allows the panels to deploy out to their position.”
NASA is still years away from building a full-sized working prototype (the current prototype expands to a diameter of 4.1 feet). There are also plenty of issues to work out, including how to activate movement in the material. “We know that they unfold nicely,” Trease said. “But we can’t have a team of astronauts out there doing the unfolding for us.” NASA has been toying with motors that would pull the material and shape memory alloys, which shift shape when an electrical current runs through it.
Finding a material that can withstand this kind of repeated stress is still in the works. “Origami has historically been done in paper. Now we’re looking at, how do you fold metals? How do you fold plastics?” Trease said, adding that it is also a matter of how many times the material can be folded and unfolded before it wears out.