The Washington PostDemocracy Dies in Darkness

Scientists want to send a fish-like ‘soft robot’ to swim the oceans of Europa

Artist's rendering of a squid- or lamprey-like robotic rover that can swim though oceans. (NASA/National Science Foundation)

Europa, one of the many moons of Jupiter, is a very promising address in the solar system for those who say it's possible we'll find life beyond Earth right here in the Milky Way. For one thing, researchers have pretty good evidence that a giant liquid ocean exists below the moon's icy crust. A group of researchers at Cornell has come up with an idea for an animal-like underwater rover that could one day explore Europa.

The "soft robot" proposal just won a $100,000 grant from NASA's Innovative Advanced Concepts initiative -- an award for project ideas that are at the cutting edge of the tools we have to explore space. The proposed rover looks more like a squid than a robot, and that's intentional: Soft robots are intended to "move more like a natural organism," co-principal investigator Rob Shepherd said in an interview with The Washington Post.

[Remastered image shows the icy surface of Jupiter’s moon in living color]

Shepherd is one of the researchers exploring the possibilities of soft-machine building, a field of research that is still in its early stages.

Below is an early soft robot Shepherd worked on:

Cornell and Harvard researchers have created a flexible, rubber-like robot for use in search and rescue missions that can withstand the most extreme elements. (Video: Reuters)

When thinking about what kind of rover would be best suited to Europa's oceans, "we thought it would be a good idea to make machines that swim like our own terrestrial ocean animals," Shepherd said.

In fact, the Cornell robot bears a stronger resemblance to another, more ancient underwater creature found on Earth: a lamprey. Lampreys are simple, eel-like creatures that have changed little in hundreds of thousands of years. They're living fossils. Shepherd said the idea to base the rover on a lamprey came from the advice of an evolutionary biologist at Cornell, William Bemis.

Lampreys are great models for a swimming robot "primarily because of [their] relative simplicity," Shepherd said. Their simple design is pretty well-tested by the evolutionary process. The researchers are even borrowing a little from the lamprey's mouth: instead of a jaw, the creature has a toothed, suction-like opening. The rover might have a similar opening that it could use for "grasping or anchoring things," Shepherd said.

[Why NASA’s top scientist is sure that we’ll find signs of alien life in the next decade]

Although the Europa rover won't feed like a lamprey, it is, in a way, intended to be a scavenger.

Shepherd's co-principal investigator Mason Peck -- a mechanical and aerospace engineering expert -- has proposed a power system for the rover that would extract from the resources that surrounds it. First, Peck said in a statement, the rover would have "tentacle-like structures that serve ... as electrodynamic tethers to harvest power from locally changing magnetic fields." That scavenged energy would power other systems on the robot, including its propulsion system.

The process begins by electrolyzing water to produce hydrogen and oxygen gas, which then fills up the rover's internal chambers. A spark would prompt the elements to combust, which should recombine them into water. The effect would be an inflation and deflation of the chambers, propelling the robot around Europa's seas, Cornell said in a statement. "The bio-inspired technologies we propose to consider bypass the need to power rovers with limited-lifetime batteries, large solar arrays or nuclear power," Peck said. "In this one respect, it is a breakthrough concept."

Oh, and one more thing about this robot: Its skin is also going to be electroluminescent. "We've developed some material that simulates a lot of the functions of an octopus," Shepherd said. The Europa rover's skin will emit a white light that can illuminate its path and make underwater imaging possible.

As the project proposal progresses, the researchers are hoping to learn more about why Earth's underwater creatures evolved in the way they did, and which of those features might potentially be useful to future explorations. It "would be nice if we could replicate even some of these capabilities," Shepherd said.

Want more science? Give these a click. 

Why Sir David Attenborough, at 89, can’t and won’t stop documenting nature

New NASA images shed a little light on those mysterious Ceres bright spots

The Curiosity Mars rover caught a stunning blue sunset on the Red Planet