MIT designed these tiny R2-D2 robots to help keep spaceships safe

The idea of having robots aiding humans in spaceships, orbital stations, and bases in remote planets is as old as sci-fi itself, but it’s taken decades for someone to come up with an idea for an “astromech” (think R2-D2 from Star Wars) that actually makes sense and doesn’t feel like a gimmick.

Created by an engineering team at the Massachusetts Institute of Technology, and led by graduate student Fangzheng Liu, AstroAnts are rovers roughly the size of a Hot Wheels toy car. They creep around the surfaces of space vehicles and structures using magnetic wheels, each armed with different sensors to monitor the ship’s constants inch by inch. The idea is that, by constantly watching over the temperature and structural integrity of their cosmic rides, spaceships will be more resilient to the extreme conditions of space and astronauts will be safer.

Monitoring a spaceship’s health

Right now, humans in space rely on a very limited set of sensors placed in their spaceship to keep tabs on the well-being of their capsules and habitat modules. When micrometeoroids impact their surface at several times the speed of sound, or as hardware wears down due to aging, mistakes, or any other reason, the crew might not necessarily learn about these incidents with enough time to fix them.

It can be hard to pinpoint problems on spacecrafts. Like, for instance, when the ISS detects a drop in pressurization due to a tiny hole in the hull. On occasion, the issue can’t be fixed because it is a fatal error, like what happened during the Apollo 13 mission, when the spaceship’s oxygen tanks ruptured because of a combination of technical malfunctions, wiring issues, and prior damage that occurred during ground testing.

That explosion happened when a fan inside the oxygen tank was turned on, causing a short circuit in the damaged wiring, which led to a catastrophic failure. At the time, no real-time system existed to monitor internal conditions of the spacecraft’s components in detail, making it impossible to predict or prevent this specific failure. 

Perhaps if the Apollo 13 craft had had some AstroAnts roaming the interior of the ship, passing by the oxygen tank area and other components, they might have detected early signs of the internal damage or wiring faults using their sensors—things that were invisible to the crew at the time. Even if the rupture wasn’t entirely avoidable, having AstroAnts moving around the spacecraft could have potentially allowed earlier detection of structural anomalies or temperature irregularities before the catastrophic event occurred.

And while that is speculative historical fiction, detecting problems that may put missions at risk is what AstroAnts are designed to do, as Dr. Cody Paige, Director of the MIT Media Lab’s Space Exploration Initiative, tells me over a video conference. Working in swarms, the tiny roaming robots can be equipped with various sensor payloads to inspect the surfaces of spacecraft, monitor temperature, detect punctures, and do anything engineers can imagine depending on their payload. “Liu is developing a version with a small hammer to identify issues beneath the surface,” she says.

The development of the AstroAnt

The AstroAnts project began its life in the weirdest, most tangential way imaginable, Paige tells me. “The AstroAnts actually started with another student as a wearable device,” she says. “They were very tiny robots designed to move around on the surface of clothing.” 

That wearable technology quickly evolved into something with far greater implications. “[The concept] was then developed into a space application, and Fangzheng Liu took that to the current project, which is the AstroAnt,” Paige explains.

Each AstroAnt is equipped with four magnetic wheels, allowing it to cling to and navigate any metallic surface. They can do their job on landers and rovers on another planet, the International Space Station, a spaceship en route to the Moon or Mars, or anything you can imagine. “As long as there’s a magnetic surface, it will work,” Paige points out. 

The AstroAnt’s strength lies in its versatility and resilience, a product of their networked nature. Designed to work together as swarms, they will monitor the health of spaceships, rovers, and space stations, operating together to cover vast areas that would be so dangerous or time-consuming to inspect visually that it will be impossible to do for humans.

“If you had a swarm of AstroAnts that could rove around the outside of the space station and find where that [micrometeoroid] impact might be… that could save a lot of time and make it safer,” Paige explains. An AstroAnt in the swarm can find the puncture quickly and warn the crew, so they can easily go there to fix it if it needs to be fixed. 

The alternative, Paige points out, would be to cover the entire surface of a ship with tens of thousands of sensors, something that wouldn’t be cost effective, and would add extreme complexity and extra weight to the vehicle.

The current design of AstroAnts could inform a more sophisticated future generation of swarming bots that can maintain ships in addition to their monitoring abilities. Remember that scene in Star Wars: The Phantom Menace in which R2-D2 goes out on a spaceship fuselage, magnetically attached to the surface, to find and repair some damaged wiring? The AstroAnts may one day do exactly the same thing, making sure that a spacecraft or a Mars base is always in perfect condition. Except that it will be an army of ants, not a single astromech.

Big test to the Moon

The first AstroAnt test is coming in January 2025, when a single wheeled critter makes its way to the Moon riding aboard the Nova-C lunar lander on NASA’s Commercial Lunar Payload Services program, as part of the Impossible Machines’ IM-2 mission.

The lander will carry the Mobile Autonomous Prospecting Platform (MAPP) rover, built by Colorado-based Lunar Outpost. Designed to explore the lunar South Pole, the rover will emerge from the lander to start its mission. The AstroAnt will be comfortably parked in a tiny garage on top of the rover itself. Once the MAPP is rolling, the AstroAnt will exit its parking spot and begin the task of taking temperature readings across the rover’s surface. “The AstroAnt charges in the small garage and, once deployed, it will collect temperature data in small pixel-like chunks, creating a map of thermal conditions on the rover,” Paige says.

While AstroAnts are designed to work as networked bots in larger swarms, only one AstroAnt will be sent largely due to the expense. “We’re academics, so we want to test one before we send up a whole fleet of them,” Paige laughs. But this mission will be an important proof of concept, and it is expected that future iterations will involve full swarms of these robots.

Liu and the rest of the AstroAnt team—visiting scientist Ariel Ekblaw and MIT Space Exploration Initiative Mission Integrator Sean Auffinger—tested the AstroAnts earlier in 2024, traveling to Lanzarote, Spain, where the volcanic landscape resembles the moon. The results were promising, providing critical data on the robot’s ability to maneuver and collect information. According to their testing, the robots will not have any problem traveling across metallic surfaces even with 80 degree angle changes.

Industrial applications too

While AstroAnts are designed to operate space, they can work just as great here on Earth. Their modular, mobile swarm design could make them the perfect solution for constantly inspecting hard-to-reach places like the inside of industrial machines, big complex factories, power centrals, airplane engines, industrial transformers, refineries, or any other kind of complex infrastructure. Anything that is dangerous, too big, too small, and needs close monitoring will be the perfect homes for these robotic swarms.

The industry is already watching, as Paige notes without mentioning the company names. “There’s interest in using something like this for hard-to-reach places like inside an engine,” she says. By constantly monitoring these installations and machines, the robots can provide an invaluable service to prevent critical failures, fix problems before they turn into something bigger, and keep them working at a lower cost.

Whether it is here on Earth, in orbit or on Mars, AstroAnt swarms truly have the potential to fundamentally change the way we design and operate machines, vehicles, and structures of any kind. By utilizing swarming robots instead of fixed sensors, everything we can imagine can become nimbler, more efficient, more adaptable, and a lot cheaper and safer to operate in the long run.