Inspired by origami, engineers at NASA’s Jet Propulsion Laboratory have developed a Pop-Up Flat Folding Explorer Robot (PUFFER) with a lightweight design and the ability to flatten itself, tucking in its wheels to crawl into places that rovers cannot fit.
The team has tested PUFFER in a range of rugged terrains, from the desert to the snow hills of Antarctica. The PUFFER robot would venture into areas that might be too risk for a full-fledged rover to go to, such as steep slopes or behind sand dunes.
The robot is designed to skitter up 45-degree slopes, investigate overhangs, and drop into pits or craters. Because the PUFFER is a microbot that can be flattened and stacked on top of other PUFFERs, it would function like a hardy assistant to the rover or a larger robot companion.
“They can do parallel science with a rover, so you can increase the amount you're doing in a day,” said Jaakko Karras, PUFFER's project manager at JPL.
“We can see these being used in hard-to-reach locations – squeezing under ledges, for example.”
While PUFFER has been engineered for interplanetary applications, it could have terrestrial uses as well, especially for geology. Carolyn Parcheta, a JPL scientist who uses robots to explore volcanoes, says robots that can fold up and fit in backpacks could be very handy.
“Having something that's as portable as a compass or a rock hammer means you can do science on the fly,” she said.
PUFFER's body was originated by Karras, who was experimenting with origami designs. The team substituted the traditional origami substrate – paper – with a printed circuit board.
“The circuit board includes both the electronics and the body, which allows it to be a lot more compact,” said Christine Fuller, a JPL mechanical engineer who worked on PUFFER's structure and tested it for reliability.
The robot was engineered to be fully integrated, and thus does not require mounting fasteners or other parts.
The team then made four wheels for the robot on a 3D printer. While the first PUFFER prototype was little more than rolling origami, the robot quickly grew more complex. The wheels were cut down from four to two, but with treads that allow the robot to climb inclines. They can also be folded over the main body, allowing PUFFER to crawl. A tail was added for stabilization. Solar panels on PUFFER's belly allow it to flip over and recharge in the sun.
The team also developed a skittering walk that keeps the bot inching forward, one wheel at a time, without slipping. They also worked with a partner to integrate a high-resolution microimager sensitive enough to see objects that are just 10 microns in size.
In tests on landscapes that are like Martian landscapes, PUFFER can drive 625 m on one battery charge. It can also operate in snowy conditions.
The next step is to add more instruments to PUFFER, allowing it to sample water for organic material, or to study the chemical makeup of its environment. The team is also looking at larger versions of PUFFER, which would no longer be a microbot, but have the advantage of added robustness. Future versions could also run autonomously.
[Image: PUFFER was outfitted for field testing in snow during a recent trip to Antarctica's Mt. Erebus. Credit: Dylan Taylor.]