The Steampunk Rover Concept That Could Help Explore Venus
50 years after the first spacecraft touched down on our super hot neighbor (and promptly died), NASA has a plan for a tougher mechanical lander.
IT’S NOT EASY being Venus. Despite being nearly identical in size to Earth, our sister world suffers from a choking greenhouse effect, a surface covered in permanent sulfuric acid clouds, and average temperatures hot enough to melt lead. Most digital devices will get swiftly destroyed under such conditions, which makes planning a robotic rover that can survive long-term a challenge.
So, thought Jonathan Sauder, a mechatronics engineer at NASA’s Jet Propulsion Laboratory in California, why not go analog?
Rather than relying entirely on state-of-the-art components, a mechanical automaton built from high-temperature steel and titanium could travel over Venus’ scorching terrain, using clockwork sensors to avoid obstacles while collecting power from wind and storing it in a wind-up spring. Though it sounds like the basis of some retro-future sci-fi novel in which the Victorians explore the solar system, a rudimentary version of Sauder’s vision is being built and tested in the modern day.
It’s been 50 years since humanity first landed on the closest planet to Earth—the Soviet Venera 7 mission touched down on December 15, 1970—and decades since any space agency has gone near the Venusian surface. But the controversial detection of phosphine gas, a molecule often produced by living organisms, in Venus’ atmosphere has drawn increased attention to the dearth of data regarding our strange sibling. In order to understand the limits of habitability on planets around other stars, researchers need new probes that can explain why Venus ended up so different than our world. Innovative concepts like an automaton rover could conceivably be part of our future plans.
The idea for such a wild machine first came to Sauder around five years ago during a coffee break at JPL, when he and his colleagues sat around discussing novel planetary explorers, mechanical computers like Babbage’s Difference Engine, and the spindly, mobile Strandbeest creations of Dutch artist Theo Jansen. “We said: ‘What if you got rid of all the electronics? What if you made a steampunk mission?’” Sauder recalls.
Youthful and enthusiastic, Sauder talks a mile-a-minute and seems to possess a brain working a few notches faster than he speaks. On his website, he describes his career experience using the ’80s TV show MacGyver, writing about using adaptability and resourcefulness to overcome difficult problems. He and his coauthors first won funding to develop their clockwork rover proposal from NASA’s Innovative Advanced Concepts (NIAC) program, which incubates off-the-wall thinking, in 2016.
Initially named the Automaton Rover for Extreme Environments (AREE), the team’s plans are still in development, with the latest prototype being a roughly quarter-size model that recently tested obstacle-avoidance and internal gearworks in a NASA chamber simulating Venus’ hellish conditions. The chamber’s high temperatures oxidized the robot’s steel frame, imbuing it with a burnished orange-brown tint and furthering its steampunk appearance. Yet the pint-size bot aced its ordeals without breaking a sweat.
An actual rover like this wouldn’t be ready to fly for at least 10 years. But, said Sauder, such a span between proposal and utilization is fairly standard for planetary missions. Other current Venus rover ideas are targeting the 2040s and would require advancements in high-temperature digital components, so Sauder feels like his project is competitive. “The work we’re doing today is applicable to many potential Venus rover missions, even ones which may rely on much further advances in high-temperature electronics,” he says.
Among the many problems robots have with surviving on the Venusian surface is the lack of good power sources. Cloud cover limits the usefulness of solar cells, and nuclear reactors need to dispose of waste heat—hard to do when the ambient air is nearly 900 degrees Fahrenheit. Though wind speeds average a sedate 2.2 miles per hour, the thick atmosphere can still impart a good deal of force to the blades of a windmill. Directly running the gears of a rover using such a turbine, or storing some power in a spring, would be much more efficient than sending it into a generator to produce electricity and then moving a motor.
Sauder and his engineers first considered instruments that could measure temperature and pressure using basic physical properties like thermal coefficients of expansion, mechanical seismometers, and even recording their data on a golden record that would loft up with a balloon to an orbiting spacecraft. (“Too much of a Rube Goldberg,” he concluded.) They flew Jansen to California to consult about a spider-legged walking robot, though the artist told them that his Strandbeests tend to fail on landscapes that aren’t a flat beach. Eventually, though, reality intervened. High-temperature electronics being developed at NASA’s Glenn Research Center in Ohio were capable of taking much better measurements than the group anticipated, beating anything a mechanical instrument could do.
One area that’s still lagging is developing cameras that won’t melt on our sister world. Mars rovers use detailed image processing for their obstacle-avoidance programs, but without the ability to take high-quality pictures, such a package would be hard to adapt for Venus. So the JPL engineers are currently developing a concept they call the Hybrid Automaton Rover-Venus (HAR-V, or Har-vee) that would essentially be a wind-driven, wheeled mobility platform capable of carting sensitive electronics around for up to 120 days. Like a boat, it could “sail” with the wind and follow the breeze to navigate.
Such a system could run circles around the first human-made object to reach the Venusian regolith, Venera 7. After their first few attempts with more fragile landers failed catastrophically, Soviet engineers realized that Earth’s evil twin has surface pressures that can crush a submarine, so they massively overbuilt their next probe. “It was basically an inch-thick titanium sphere,” says Don P. Mitchell, a computer programmer and historian of Russia’s Venus exploration. “They were like: ‘This time, damn it, we’re going to get to the surface.’”
A Space Age kid, Mitchell grew up seeing low-quality images from the Venera program “that looked like they were photographed off a newspaper.” In 2000, a friend showed him a film recording from Venera 9 and he realized the probes were actually pretty powerful. By contacting former Soviet scientists, he obtained raw data from the missions, processing it himself to produce fantastic pictures, which are now available on his website.
Venera 7 didn’t include any cameras and was only a partial success. After conducting humanity’s first soft landing on another planet in the solar system, it tipped over, misaligning its antenna. A part responsible for switching between different instruments failed, and so the poor probe just kept sending back temperature readings over and over. Its batteries expired 23 minutes later.
In perhaps the most Cold War story ever, Mitchell recalls how the first NASA scientist to obtain Venera 7 data, John Edgar Ainsworth, was handed the information by a CIA agent shortly after the lander touched down. The American intelligence community had intercepted the Soviet robot’s signal using a radio telescope in Ethiopia. “Someone gave [Ainsworth] an envelope and said, ‘I can’t tell you where this came from.’ It was the Venera data,” says Mitchell. Using that, the US researcher coauthored a paper on the probe’s descent through the bumpy Venusian atmosphere.
Russia had more success with subsequent Venera probes, which sent back the only photos and measurements from the Venusian surface we have to this day. NASA, the European Space Agency (ESA), and the Japan Aerospace Exploration Agency (JAXA) have since orbited the planet next door, but no dedicated mission has launched to Venus from US soil in 31 years. That might soon change. “We are potentially at the cusp of a new era of Venus exploration,” says Paul Byrne, a planetary scientist at North Carolina State University and self-described Venus evangelist. Deeply knowledgeable and gregarious, Byrne is one of many researchers helping to lead the charge back to our sister world.
Astronomers have detected thousands of planets around other stars, some roughly the same size as Earth that are situated in just the right place for liquid water to exist on their surfaces. Though scientists have long thought that Venus is too close to the Sun to have ever been habitable, new models propose that the planet might have hosted oceans for nearly 3 billion years, while other data indicates that Venus could still be tectonically active today. A massive series of volcanic explosions or outgassing events might have dumped carbon dioxide into its atmosphere sometime in the past, overwhelming its ability to thermoregulate and creating its present infernal environment. “If that’s true, and Venus got ruined by random coincidence and not because of the sun, we might be able to look at worlds closer to their parent systems,” says Byrne.
The list of other open questions about our sibling include the exact composition of the atmosphere, the nature of the large continent-like features on its surface, what is happening in its core, and what makes up the mysterious substance absorbing ultraviolet radiation in its upper cloud layers. Essentially, scientists want to study Venus top to bottom, inside and out, and from the distant past to the modern day. “We need a program of research to understand the planet,” says Byrne. “No one or two or five missions can answer all these questions.”