Robotic “SuperLimbs” Aid Astronauts to Recover from Falls

Massachusetts Institute of Technology, Cambridge, MA

SuperLimbs, a system of wearable robotic limbs built by MIT engineers, is designed to physically support an astronaut and lift them back on their feet after a fall, helping them conserve energy for other essential tasks. Pictured, from left, is Sang-Yoep Lee, Harry Asada, and Erik Ballesteros. (Image: Jennifer Chu)

Need a moment of levity? Try watching videos of astronauts falling on the Moon. NASA’s outtakes of Apollo astronauts tripping and stumbling as they bounce in slow motion are delightfully relatable. For MIT engineers, the lunar bloopers also highlight an opportunity to innovate.

“Astronauts are physically very capable, but they can struggle on the Moon, where gravity is one-sixth that of Earth’s but their inertia is still the same. Furthermore, wearing a spacesuit is a significant burden and can constrict their movements,” said Professor Harry Asada. “We want to provide a safe way for astronauts to get back on their feet if they fall.”

Asada and his colleagues are designing a pair of wearable robotic limbs that can physically support an astronaut and lift them back on their feet after a fall. The system, which the researchers have dubbed Supernumerary Robotic Limbs or “SuperLimbs,” is designed to extend from a backpack, which would also carry the astronaut’s life support system, along with the controller and motors to power the limbs.

The researchers have built a physical prototype, as well as a control system to direct the limbs, based on feedback from the astronaut using it. The team tested a preliminary version on healthy subjects who also volunteered to wear a constrictive garment similar to an astronaut’s spacesuit. When the volunteers attempted to get up from a sitting or lying position, they did so with less effort when assisted by SuperLimbs, compared to when they had to recover on their own.

The MIT team envisions that Super-Limbs can physically assist astronauts after a fall and, in the process, help them conserve their energy for other essential tasks. The design could prove especially useful in the coming years, with the launch of NASA’s Artemis mission, which plans to send astronauts back to the moon for the first time in over 50 years. Unlike the largely exploratory mission of Apollo, Artemis astronauts will endeavor to build the first permanent Moon base — a physically demanding task that will require multiple extended extravehicular activities (EVAs).

“During the Apollo era, when astronauts would fall, 80 percent of the time it was when they were doing excavation or some sort of job with a tool,” said Team Member Erik Ballesteros. “The Artemis missions will really focus on construction and excavation, so the risk of falling is much higher. We think that SuperLimbs can help them recover so they can be more productive and extend their EVAs.”

Asada, Ballesteros, and their colleagues will present their design and study this week at the IEEE International Conference on Robotics and Automation (ICRA). Their co-authors include MIT postdoc Sang-Yoep Lee and Kalind Carpenter of the Jet Propulsion Laboratory.

The team’s design is the latest application of SuperLimbs, which Asada first developed about a decade ago and has since adapted for a range of applications, including assisting workers in aircraft manufacturing, construction, and ship building.

For more information, contact Abby Abazorius at This email address is being protected from spambots. You need JavaScript enabled to view it.; 617-253-2709.