A smart exoskeleton that recognizes balance loss—and prevents falling—has been developed by researchers at Scuola Superiore Sant’Anna (SSSA), Pisa, Italy, and École Polytechnique Féderale Lausanne (EPFL), Switzerland. The exoskeleton, which is worn from the waist down, has been tested at the rehabilitation center Fondazione Don Carlo Gnocchi, Florence, Italy. This is said to be a first in wearable machines, which are normally used to assist or enhance regular movement, instead of preventing an unexpected event like falling, but this version could also be used by people with physical impairments, amputations, and neurological disorders. The test results were published online May 11 in Scientific Reports.
“Our smart exoskeleton is lightweight and extremely easy to personalize,” said Silvestro Micera, PhD, a professor at EPFL and SSSA, and the Bertarelli Foundation Chair in Translational Neuroengineering at EPFL. The device is equipped with motors at the hip and carbon fiber braces. For this first prototype, the exoskeleton requires only a few minutes to adapt to a given patient, which involves adjusting several nuts and bolts until it is sized to the user and learning the user’s gait.
“I feel more confident when I wear the exoskeleton,” said Fulvio Bertelli. He had trialed the machine on a special treadmill that can artificially make him lose his balance and slip.
The personalized exoskeleton first detects the characteristics of the user’s gait. Once this pattern is established, the system’s algorithm detects deviations from his normal gait, i.e. the onset of a fall. When this happens, the motors push both of the thighs down, reestablishing the user’s stability at the hip.
An important aspect of the system is to ensure that the exoskeleton is nonintrusive. It should not unnecessarily disturb the user, particularly when the user is not falling. The next steps involve making the exoskeleton more discrete and portable for the outside world, and to test its usability with end users in real-life environments.
Editor’s note: this story was adapted from materials provided by EPFL.
The exoskeleton interacts with users during reactive motor responses, such as accidental slipping. Photograph courtesy of EPFL.