NASA and many other space agencies around the world are eager to get back to Venus. And this time around, they want to send missions that can explore the surface for more than a few hours! To this end, engineers at NASA’s Jet Propulsion Laboratory (JPL) and Glenn Research Center (GRC) are investigating “steampunk” concepts and special electronic systems that will allow rovers to work in Venus’ hellish environment.
In February of 2020, NASA also launched a public competition through HeroX to seak ideas for rovers that would be capable of surviving the extreme conditions on Venus’ surface – the “Exploring Hell Challenge“. After months of consideration for all the worthy submissions they received, NASA recently announced that it in addition to three winning concepts, they have selected two additional finalists and ten honorable mentions!
To break it down, Earth and Venus have a number of similarities, to the point that Venus is colloquially referred to as Earth’s “Sister Planet.” But beyond being terrestrial (rocky) and orbiting within the Sun’s habitable zone, our two planets are vastly different. The average temperature on the surface of Venus – 737 K (462 °C; 864 °F) – is hot enough to melt lead and the atmospheric pressure is 92 times that of Earth’s at sea level (9.2 MPa).
While multiple missions have been sent to Venus to learn more about its atmosphere and surface features, only a handful have ever attempted to land there. Those that actually made it only survived a short time before their electronics failed and they could no longer send back information. The longest-surviving mission was the Soviet Venera 13 probe that landed on Venus in 1981 and managed to transit for 127 minutes.
The last spacecraft to land on Venus was the Soviet Vega 2 mission in 1985, which survived only 52 minutes. As such, designing a rover that can survive on the surface of Venus is no small task. For their part, engineers at JPL have been working on a design for an analog rover known as the Automaton Rover for Extreme Environments (AREE), which began as a NASA Innovative Advanced Concepts (NIAC) study in 2017.
AREE would use a small wind turbine and a system of springs to generate and store mechanical energy that would power its locomotion. It would also rely on a system, gears, and components made from heat-resistance allows, and limited-capability electronics, rather than a conventional system of computers and sensitive electronics. Such a simple and robust machine could theoretically last for months on the surface of Venus.
However, there’s still the challenge of navigating Venus’ terrain, which would be very difficult without advanced electronic sensors. This was the main focus of NASA’s “Exploring Hell: Avoiding Obstacles on a Clockwork Rover” challenge, which received 572 submissions from 82 countries. These ranged from systems of rollers that would detect hazards to oversized fenders that would push rover in reverse if it encountered an obstacle.
As Jonathan Sauder, a senior mechatronics engineer at JPL, said in a recent NASA press statement:
“The response from the community was incredible and better than I ever dreamed. There were so many great ideas and well-developed concepts that in addition to first, second, and third place, we decided to add two finalists and another 10 honorable mentions in recognition of the amazing work people put into this project.”
The top three prizes, which were provided by the NIAC and NASA Prizes and Challenges programs, included a cash prize of $15,000 for first place, $10,000 for second, and $5,000 for third. The finalists were also awarded the privilege of being considered to join AREE’s design team as the rover concept continues to develop.
First place went to Youssef Ghali, an architect and designer from Cairo, Egypt, for his “Venus Feelers” concept (video above). Based on the AREE design, this rover employs a windmill to drive a system of gears and compression springs. Meanwhile, a three-part system known as the Obstacle Avoidance Sensor (OAS) allows the rover to sense depressions, obstacles, and sloping surfaces in the terrain ahead.
The first part of this system is the two front-mounted wheels (which resemble fidget spinners) that detect holes in the ground. Second, there’s a bumper-like assembly that instructs the rover to back up if it encounters large rocks. Last, there’s the Slopes Detection System, which is comprised of two identical devices that detect the pitch tilt and the roll of sloped terrain.
“I’m grateful for the opportunity and that [these] sort of challenges are open to the general community, people who are enthusiastic about innovation and sharing their thoughts and designs,” expressed Ghali to Universe Today.
Second place went to mechanical engineers Martin Grabau and Eric Seeberger of Team Rovertronics, from Santa Barbara, California. Their concept, “Skid n’ Bump – All-mechanical, Mostly Passive” (video above) consists of a low, box-like rover that relies on a front-mounted arm and trigger mechanism to sense the terrain ahead and adjust the rover’s course.
Third place went to mechantronics engineer Callum Heron of Brisbane, Australia, for his “Direction Biased Obstacle Sensor (DBOS).” This rover also relies on a windmill to drive clock springs and a Sterling engine while a sophisticated series of rollers sense the gradient and roughness of the terrain ahead of the rover, as well as rocks, depressions, and other obstructions.
In addition to the top three winners, the judging panel also established two additional prizes – titled “Best Prototype” and “Most Innovative” awards with cash prizes of $2,000 each. The former went to Kristine Berza and Oskars Berzs and their design company KOB ART, from Riga, Latvia. Their concept, “AMII Sensor,” also employs a front-mounted set of mechanical sensors that instruct the rover how to navigate over varied terrain.
The “Most Innovative” prize went to Matthew Reynolds, a Chartered Mechanical Engineer from York, UK, for his “Evaluate Cliffs Holes Objects & Slopes (ECHOS)” design. This rover employs a remote hole detector that relies on a mechanical sonar device to detect large holes in the terrain ahead of the rover.
These and other rover concepts could be exploring the surface of Venus in the coming years. That surface, shrouded in a virtually impenetrable layer of toxic clouds and sulfuric acid rain, holds a lot of secrets that scientists are eager to reveal! Among these are the existence of present-day volcanism, the reason for its transformation, and the possible existence of oceans (and even life!) on its surface long ago.
Further Reading: NASA, HeroX