NASA’s PUFFER Microbot Has 3D Printed Wheels to Climb Up Martian Slopes

The rovers that could be used to explore the moon, or other planets in our galaxy, are increasingly being designed and built using 3D printing technology, like Part Time Scientists’ Audi-sponsored 3D printed moon rover and 3D printed Mars Rover components by Ogle Models & Prototypes. Scientists at NASA’s Jet Propulsion Laboratory (JPL) in California have been busy developing a little robot, with some help from 3D printing, that could potentially tag along with a larger rover. The lightweight Pop-Up Flat Folding Explorer Robot, or PUFFER, can tuck in its own wheels, flatten itself, and crawl up and into tight spaces that rovers can’t access.

PUFFER was actually inspired by origami, and has been tested in several rugged terrains over the last year and a half. It’s meant to be a type of rover assistant, and investigate places that could be considered “too risky” for full-size rovers, like behind sand dunes or up slopes. PUFFER is really a microbot, and was designed so that several could be flattened out and stacked on top of each other for maximum space-saving capabilities; then, when they’re ready to go to work, multiple PUFFERs can be removed, popped up, and get going. It can check out potentially dangerous overhangs, ascend 45° slopes, and drop into craters without being damaged.

JPL’s PUFFER project manager Jaakko Karras said, “They can do parallel science with a rover, so you can increase the amount you’re doing in a day. We can see these being used in hard-to-reach locations – squeezing under ledges, for example.”

The PUFFER program, managed by JPL, is a Game Changing Development program, which is part of NASA’s Space Technology Mission Directorate. The program investigates approaches and ideas which could potentially “solve significant technological problems and revolutionize future space endeavors.”

Karras came up with PUFFER while he was experimenting with origami designs and nature-inspired robotics during his time as a grad student at UC Berkeley’s Biomimetic Millisystem Lab. The PUFFER prototype first featured paper, and then the team switched that out for a printed circuit board, in order to “incorporate more electronics, including control and rudimentary instruments.”

JPL mechanical engineer Christine Fuller, who worked on PUFFER’s structure and reliability testing, said, “The circuit board includes both the electronics and the body, which allows it to be a lot more compact. There are no mounting fasteners or other parts to deal with. Everything is integrated to begin with.”

PUFFER continued to evolve: JPL robotic mobility specialist Kalind Carpenter 3D printed its four wheels, which later went down to two wheels with tread. The wheels can now be folded over the body of the microbot, so PUFFER can crawl; a tail helps stabilize it. PUFFER can also flip over and expose its solar panels, so it’s able to recharge in the sun. The PUFFER team gained a sensitive, high-resolution microimager from Illinois-based Distant Focus Corporation, which allows PUFFER to see objects that are only 10 microns in size, and the Biomimetic Millisystems Lab helped the team work out PUFFER’s signature “skittering walk,” which helps it inch up, one wheel at a time, without slipping and falling over…a good trait to have if it will be climbing up slopes on Mars.

When the prototype was functioning, the team took it for a field test in Rainbow Basin, California, and PUFFER stretched its wings…wheels…and climbed underneath overhangs and up rock slopes, which it would also encounter on Mars. One battery charge can take PUFFER about 2,050 feet on a level dirt path, although the team notes that the time is subject to change, once it factors in how many onboard instruments PUFFER could eventually be equipped with. PUFFER then got a flat fishtail and bigger wheels for snowy terrain, and was field tested at two ski resorts, and in Antarctica, on active volcano Mt. Erebus. PUFFER also delighted tech fans at CES in January.

Now, JPL’s PUFFER team will be making future designs even bigger, and adding scientific instruments, like a spectrometer to study the surrounding environment’s chemical makeup, or an instrument that lets PUFFER sample water and check for organic material. JPL scientist Carolyn Parcheta, who uses robots to explore volcanoes, helped with PUFFER’s scientific instruments, and noted the potential of backpack-ready little robots in geology and similar fields.

Parcheta explained, “Having something that’s as portable as a compass or a rock hammer means you can do science on the fly.”

PUFFER currently runs off Bluetooth and can be controlled remotely, but Carpenter explained that the team hopes to “add autonomy” and make a mobile team of PUFFERs.

Carpenter said, “If Curiosity had a stack of PUFFERS on board, each of them could go to separate spots, and the rover would just go to the most interesting one.”

PUFFER is already equipped with some Mars-compatible materials, in case it ever gets to go to space. Its body is wrapped in strong textile Nomex, used by firefighters to repel heat; it also cushioned the air bags of NASA’s Opportunity and Spirit rovers.

“Small robotic explorers like PUFFER could change the way we do science on Mars. Like Sojourner before it, we think it’s an exciting advance in robotic design,” said Karras.

Discuss in the PUFFER forum at 3DPB.com.

[Source: NASA’s Jet Propulsion Laboratory]