In a new study, researchers explored how muscles powered by artificial intelligence and made from lifelike materials paired with intelligent control systems can make prosthetic limbs feels natural, responsive, and safe. The technology can also learn from the body and adapt in real time.
“When people think of robots, they usually imagine something like The Terminator or RoboCop: big, rigid, and made of metal,” said Hong Yeo, PhD, the G.P. “Bud” Peterson and Valerie H. Peterson Professor in the George W. Woodruff School of Mechanical Engineering at Georgia Tech, and an author of the study. “But what we’re developing is the opposite. These artificial muscles are soft, flexible, and responsive—more like human tissue than machine.”
Yeo’s research uses hierarchically structured fibers, which are flexible materials built in layers, much like muscle and tendon. He trains machine learning algorithms to adjust those pliable materials in real time with the right amount of force or flexibility for each task.
“These muscles don’t only respond to commands,” Yeo said. “They learn from experience. They can adapt and self-correct, which makes motion smoother and more natural.”
One of the first real-world applications of the technology is a prosthetic glove powered by artificial muscles, a device that behaves more like a helping hand than a mechanical tool, mirroring the natural give-and-take of real muscle.
Inside the glove, thin layers of stretchable fibers and sensors contract, twist, and flex in sync with the wearer’s intent. The glove can fine-tune grip strength, reduce tremors, and respond instantly to the user’s movements, bringing dexterity back to tasks such as fastening a button or lifting a glass.
“These aren’t just movements,” Yeo said. “They’re freedoms.”
Creating lifelike muscles requires that they are soft but strong, responsive but safe, and avoid triggering the body’s immune system.
“We always think about not only function, but adaptability,” Yeo said. “If it’s going to be part of someone’s body, it has to work with them, not against them.”
The synthetic fibers are tested, adjusted, and tuned until they operate in sync with the body’s natural movements. Over time, they develop a kind of “muscle memory,” adapting to changing conditions. That dynamic adaptability is what separates a machine from a prosthetic that truly feels alive, Yeo said.
Yeo’s lab brings together experts in mechanical engineering, materials science, medicine, and computer science to design smarter, safer devices.
“You can’t solve this kind of problem in isolation,” he said. “We need all of it—polymers, artificial intelligence, biomechanics—working together.”
In 2023, Yeo received a $3 million NSF grant from the National Science Foundation to train the next generation of engineers building smart medical technology. His team now works closely with healthcare providers and industry partners to bring these devices out of the lab and into patients’ lives.
“If it feels foreign, people won’t use it,” he said. “But if it feels like part of you, that’s when it can truly change lives.”
The open-access study, “Empowering artificial muscles with intelligence: recent advancements in materials, designs, and manufacturing,” was published in Material Horizons.
Editor’s note: This story was adapted from materials provided by Georgia Tech.
