‘SuperLimbs’ could help astronauts recover from falls

Humans haven’t traveled to the moon since NASA’s Apollo program ended in 1972, but the Artemis program will soon return humans to the lunar surface, with the first crewed landing currently slated for 2026.

Artemis astronauts will aspire to do things humans haven’t done before, like building a habitable base to allow for long-term visits and exploring the heavily cratered lunar south pole.

Innovators across the world are working on solutions to help them achieve their goals, and to keep them safe. That includes researchers at the Massachusetts Institute of Technology (MIT), who are developing a set of wearable robotic limbs to help astronauts recover from falls.

The so-called “SuperLimbs” are designed to extend from a backpack containing the astronauts’ life support system. When the wearer falls over, an extra pair of limbs can extend out to provide leverage to help them stand, conserving energy for other tasks.

That could come in handy. The moon’s partial gravity makes maintaining balance tricky. The 12 astronauts who moonwalked on Apollo missions fell 27 times and had another 21 near misses, according to a University of Michigan study.

When astronaut Charlie Duke toppled over on the moon in 1972, while performing tests on lunar soil, it took him three attempts to get up. The study found that falls were more common when, like Duke, astronauts were collecting samples or using tools – tasks that Artemis astronauts are likely to undertake.

The seven men wearing spacesuits in this portrait made up the first group of astronauts announced by the National Aeronautics and Space Administration (NASA). They were selected in April of 1959 for the Mercury Program. In the front row, from left, are Walter M. Schirra Jr., Donald K. Slayton, John H. Glenn Jr., and M. Scott Carpenter. Standing in the back row, from left, are Alan B. Shepard Jr., Virgil I. Grissom and L. Gordon Cooper Jr.

Astronauts John W. Young (in front), command pilot, and Michael Collins, pilot, walk up the ramp at Pad 19 after arriving from the Launch Complex 16 suiting trailer during the prelaunch countdown for the Gemini-10 mission. Moments later, they entered the elevator that took them to the white room, where they could board the waiting spacecraft. Liftoff occurred at 5:20 p.m. ET on July 18, 1966.

Lunar module pilot Edwin E. Aldrin Jr., better known as Buzz Aldrin, walks on the surface of the moon near the leg of the Lunar Module (LM) "Eagle" during the extravehicular activity (EVA) portion of the Apollo 11 mission. Neil A. Armstrong, commander, took this photograph with a 70 mm lunar surface camera. While astronauts Armstrong and Aldrin descended in the Lunar Module (LM) "Eagle" to explore the Sea of Tranquility region of the moon, astronaut Michael Collins, command module pilot, remained with the Command and Service Modules (CSM) "Columbia" in lunar orbit.

Space Shuttle prime and backup astronaut crews prepare to be briefed on the use of the emergency pad escape system, known as the "slidewire," in this photo from January 6, 1981. From left to right are backup astronauts Joe Engle and Richard Truly, and primary crew commander John Young. The slidewire system provided a quick and sure escape from the upper pad platforms in case of a serious emergency.

In this photo captured in February 1984, astronaut Bruce McCandless II uses his hands to control his movement above Earth — and just few meters away from the Challenger — during the first-ever untethered extravehicular activity (EVA). Fellow crew members aboard the Challenger used a 70 mm camera to expose this frame through windows on the flight deck. McCandless was joined by Robert L. Stewart, one of two other mission specialists for this flight, on two sessions of EVA.

The astronaut crew members for NASA's STS-34 mission prepare to participate in emergency egress training at the shuttle landing facility while wearing their partially pressurized flight suits with attached cooling packs. This photo from September 13, 1989, features, from left, astronauts Michael J. McCulley, pilot; mission specialists Franklin R. Chang-Diaz, Ellen S. Baker and Shannon W. Lucid; and Donald E. Williams, mission commander.

NASA astronaut Michael Fincke (left), Expedition 18 commander; and cosmonaut Yury Lonchakov, flight engineer, attired in Russian Sokol flight suits, pose in the Unity node of the International Space Station in this photo from March 26, 2009.

Astronauts participate in NASA's SpaceX Crew-4 dry dress rehearsal in the suit room inside Kennedy Space Center's Neil A. Armstrong Operations and Checkout Building on April 20, 2022. A team of SpaceX suit technicians assisted crew members as they put on their custom-fitted spacesuits and checked the suits for leaks. Pictured, from left, are Jessica Watkins, mission specialist; Bob Hines, pilot; Kjell Lindgren, commander; and Samantha Cristoforetti, mission specialist.

NASA astronaut Eric Boe wears Boeing's new spacesuit designed for astronauts who will fly on the CST-100 Starliner. The suit is lighter and more flexible than previous spacesuits but retains the ability to pressurize in an emergency. Astronauts will wear the suit throughout the launch and ascent into orbit, as well as on the way back to Earth.

Dustin Gohmert, Orion crew survival systems project manager at NASA's Johnson Space Center, poses for a portrait while wearing the Orion Crew Survival System (OCSS) suit on October 15, 2019, at NASA Headquarters in Washington, DC. The suit is designed for a custom fit and incorporates safety technology and mobility features that will help protect astronauts while they're aboard the Orion spacecraft.

Kristine Davis, a spacesuit engineer at NASA's Johnson Space Center, wears a ground prototype of NASA's Exploration Extravehicular Mobility Unit (xEMU) during a demonstration on October 15, 2019, at NASA Headquarters in Washington. The xEMU was designed to improve on the suits previously worn on the moon during the Apollo era and those currently in use for spacewalks outside the International Space Station.

The AxEMU Spacesuit, developed by Axiom Space, builds on the technology NASA incorporated into its xEMU prototype. The AxEMU, shown here with a black cover, were unveiled during an event on March 15, 2023. The suits worn by astronauts during the Artemis III mission will be white.

A visual history of the spacesuit

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Enter SuperLimbs

SuperLimbs were developed about a decade ago by Harry Asada, a professor at MIT, and they’ve already been put to the test by aircraft manufacturing and shipbuilding workers.

Now they’re being adapted for astronauts. Erik Ballesteros, a doctoral student at MIT, spent the summer at NASA’s Jet Propulsion Lab working on SuperLimbs as part of a NASA fellowship.

The system needs a bit more work, Ballesteros said, but he hopes that it will be ready for a demonstration by January – when it will help a mannequin to stand up from a prone position.

He believes that within a year or two, it’ll be ready for a human demo, but there’s a lot the team needs to figure out first in terms of safety, he told CNN. “We can’t just duct tape and throw things together; we have to be very precise and very careful,” he said.

There could be other challenges. Dr. Jonathan Clark, an adjunct clinical professor of Neurology and Space Medicine at Baylor College of Medicine, who acted as the crew surgeon for six NASA shuttle missions and is a consultant for commercial space firms, told CNN that the extreme environment of space – from temperatures, to contaminant particles like dust, to electromagnetic radiation – can mean it’s expensive and time-consuming to get technology approved for use off planet Earth.

But, he added, the rate of innovation in space technology is astonishing. “For science fiction to go to science fact, it used to take centuries or decades,” he said. “Now it’s years.”

Ballesteros understands the stakes. He has work experience in mission control at NASA’s Johnson Space Center, where his team maintained the life support systems within the International Space Station (ISS).

Ana Diaz Artiles, an assistant professor of aerospace engineering at Texas A&M, who is not involved in the research, told CNN that the limbs could help reduce the metabolic cost of getting up. The tradeoff is that the limbs might add some weight and require more power, she said.

She added that moon dust is “super toxic” so it could be harmful for an astronaut to roll around the lunar surface as they struggle to get up – a problem SuperLimbs could help eliminate. The robotic limbs are “really cool and really useful,” she said.

“The new paradigm for astronauts”

Humans haven’t had much of an opportunity to work on the moon yet. Apollo 17 astronauts hold the record for the longest moonwalk, at seven hours and 37 minutes.

By contrast, Artemis mission participants – which will eventually include astronauts from countries like Japan too – will spend up to a week on the moon, learning to live and work away from Earth, in preparation for human expeditions to Mars. China has its own plans to get to the moon by 2030, where it will build a research station.

Ballesteros plans to spend the next few years of his PhD using a “Swiss Army Knife technique” to turn SuperLimbs into a system for astronauts that can “address different important use cases, but all be one unified design.”

SuperLimbs could help astronauts recover from falls, move efficiently, and do work.

Next up, he plans to work on getting the limbs to function as an extra pair of legs. “So, it allows you to go from point A to B a lot quicker and without using as much energy,” he said. “And if they start to lose their footing a little bit, it can help stabilize them.”

After that, he’s going to turn his attention to figuring out how the limbs can leverage tools to help with tasks like excavation, sample handling, and construction.

“I want it to become almost like a natural extension of their bodies … so the astronaut almost feels awkward not having them,” he said.

In the future, he hopes the extra limbs will become the new normal. “My goal is to make these arms become almost like the new paradigm for astronauts,” he said.