By Ryan Whitwam
Engineers have to take many things into account when designing a payload destined for orbit. Of course you want things to be as light as possible, but creating equipment that is compact and reliable is also very important. This becomes a problem when you want to equip a satellite or probe with large solar panels that can gulp down lots of photons. The key to making it all work could be an artform that predates space travel by several centuries: origami.
Researchers at NASA’s Jet Propulsion Laboratory (JPL) are working on ways to fold up components like solar panels into neat little packages like origami that can then be deployed easily when the time comes. JPL’s Brian Trease is leading the research in partnership with researchers at Brigham Young University in Utah. You’ve probably seen video of a traditional solar panel being deployed. They usually launch on spacecraft folded up accordion-style in small, squat boxes. This works well enough, but it’s not a very efficient use of space, and they can’t get much smaller as each layer of the accordion is stacked on top of the last one. As you move to larger panels, the deployment becomes increasingly prone to failure as layers of panel expand. Despite the more complex appearance of the prototype origami folding solar panel, it’s actually much easier to deploy.
Designing a solar panel with origami folds required some clever engineering — origami is intended to work with paper, but even the thinnest solar panels are several times thicker than heavy-weight paper. Each bend causes the thickness of the folds to go up, which needs to be accounted for in all subsequent folds. The team managed this by utilizing a variety of folds instead of a single repeating one to collapse the panel.
The team created a design for a solar panel that’s 8.9 feet in diameter when folded up, but expands to be 82 feet across when deployed. A scale model version of this panel can be seen in the video above opening up like a flower to its full 4.1-foot diameter with a light tug on the edges. Apparently, the crane version failed to live up to expectations. In all seriousness, though, the way it opens is actually just as important as the efficient packing. A smaller satellite (like the increasingly popular Cubesats) might need reliable solar power, but the economics don’t allow for a complicated mechanism to deploy panels. The simple and reliable origami folding panels could be just as good for small spacecraft as large ones.