AI-Powered ‘Iron Man’ Boots Could Someday Help You Walk Better

Oct. 31, 2022 – Talk about a new step forward: Stanford engineers have developed robotic boots that help you walk faster with less effort. Equipped with a motor, the boots use artificial intelligence to provide a personalized boost that’s just right for whoever is wearing them. 

Twenty years in the making, the boots represent the latest advance in exoskeleton technology, wearable devices that work with the user to provide greater strength and endurance. Kind of like a real-life Iron Man suit. 

Technology like this could be used to help people with limited mobility, like older adults or those with disabilities. But the challenge has been figuring out how to tailor these devices to each person.

“It turns out humans are very efficient walkers in a way that makes [providing] assistance difficult,” says Patrick Slade, PhD, one of the researchers who worked on the boots. “Everyone walks differently, and what works in the lab often doesn’t translate to the real world.” 

For example, some people need more of a push than others, or a slower speed to help keep them stable. 

That’s where the AI comes in – in particular, a type of AI called machine learning that uses algorithms to quickly process data and “learn” things. In this case, the boots use low-cost sensors to learn how a person walks and then adjust based on that information. 

The researchers call it “human-in-the-loop optimization.” The boots learn not only a person’s stride length and speed, but also their metabolic rate and energy use. They also measure ankle motion and force. 

The results: A person can walk 9% faster and spend 17% less energy when wearing them. That’s roughly the boost you’d expect from taking off a 30-pound backpack. 

That’s the largest improvement in walking performance of any exoskeleton to date, the researchers report in a Nature paper. And it’s about twice the reduction in effort of previous devices without machine learning. 

Next steps will involve testing the boots for those who need them the most: older adults and those with mobility issues due to disability, says Slade. 

But in the long term, boots like these could be offered to a wider audience, including athletes interested in performance training and workers who need to stand all day for their jobs. Among warehouse workers, for example, the boots could help relieve joint pain and muscle stiffness while making them more productive, Slade says. 

And the benefits would go beyond helping a body move, potentially reducing fall risk and improving quality of life and mental health, notes Carol Mack, a doctor of physical therapy and owner of CLE Sports PT & Performance in Cleveland. Although she wasn’t part of this research, she’s well-versed in the challenges of geriatric rehab, as well as those who are less mobile because of neurological issues. 

“Exoskeletons are showing promise as a new technology, and tech like this wouldn’t just help with walking speed,” she says. “It may also contribute to the type of core and hip control needed for maintaining balance. That could lead to more confidence for those with mobility impairment, and that’s a huge development.”