Researchers claim prosthetic limb breakthrough with smart silicone elastomer

London – Scientists at Imperial College London have developed a smart, silicone-based material that allows amputees to adjust the fit of their prosthetic limbs throughout the day.

Tackling a long-standing challenge in prosthetics design, the new technology, called Roliner, uses embedded millifluidic channels to adapt its shape, stiffness and volume in real time.

Controlled via smartphone, the liner can provide a looser fit when sitting or tighten up for walking, reducing pain and the risk of skin damage caused by rigid sockets.

Eight years in development, the material was designed and patented by researchers from Imperial’s department of bioengineering. Their findings were published in Nature Communications in March.

“Prosthetic limbs are often uncomfortable because they have a fixed, rigid shape,” said Dr Firat Guder, principal investigator on the project, in a recent statement.

According to Guder, even if the limbs are moulded to fit the body during manufacture, they can’t adapt to daily changes in weight, fluid levels or movement.

"Ultimately, no matter how sophisticated the limb itself is, if it cannot connect closely and comfortably with the human body, it becomes unwearable.”

Rather than modifying the prosthetic limb itself, the team focused on the liner – the flexible layer between the body and the rigid socket.

Roliner is made from silicone elastomers containing channels formed with wax-paper cut-outs during fabrication. These channels can be inflated or deflated to change the material’s structure.

“Just like a basketball, it becomes bigger and more rigid when inflated, and smaller and softer when deflated,” explained Dr Ugur Tanriverdi, an Imperial graduate and co-founder of wearable robotics start-up Unhindr.

The researchers said Roliner could help prevent blisters, sores and other complications that often lead amputees to abandon their prosthetics altogether.

"Alongside causing extreme physical pain, problems with prosthetics not fitting can also impact a person’s mental health," said Dr Tanriverdi. “They are unable to live as independently and freely as they deserve.”

Roliner also incorporates artificial intelligence to learn the user’s habits and automatically adjust fit based on factors like time of day, hormonal changes or activity levels.

The researchers aim to make the product commercially available in the UK by the end of 2025.

Beyond prosthetics, the team believes the technology could be applied to a wide range of uses – from exoskeletons and hospital beds to high-performance sports gear and astronaut suits.