Researchers at Vanderbilt University have developed a lightweight and inexpensive ankle exoskeleton to assist those with impaired lower leg muscles or those in jobs that require a lot of running or walking. Unlike previous ankle exoskeletons, the device is small enough to be worn discreetly under clothing.
Developing assistive exoskeletal structures to aid people with limited mobility is an active area of research. However, in many cases such devices can be heavy, bulky, and unwieldy, making them difficult to use and wear. To address this, researchers at Vanderbilt have come up with a lightweight exoskeleton for the ankle.
“Our design is lightweight, low profile, quiet, uses no motor or batteries, it is low cost to manufacture, and naturally adapts to different walking speeds to assist the ankle muscles,” said Karl Zelik, a researcher involved the study.
The exoskeleton weighs slightly over one pound (1/2 Kg) and includes a friction clutch component, which is not thicker than a shoe insole and therefore fits snugly under a shoe or foot. An assistive spring helps the user to generate force while walking or running and a soft sleeve holds the exoskeleton comfortably in place against the lower leg. At a cost of less than $100 to make, the device is inexpensive, making it more accessible for a variety of users.
In a first for this type of technology, the device is low-profile and so can be worn under clothing. “We’ve shown how an unpowered ankle exoskeleton could be redesigned to fit under clothing and inside/under shoes so it more seamlessly integrates into daily life,” said Matt Yandell, another researcher involved in the study.
“The potential applications are broad, from helping aging people stay active to assisting recreational walkers, hikers or runners,” said Zelik. “It could also help reduce fatigue in occupations that involve lots of walking, such as postal and warehouse workers, and soldiers in the field.”
Study in IEEE Transactions on Neural Systems & Rehabilitation Engineering: Design of a Low Profile, Unpowered Ankle Exoskeleton That Fits Under Clothes: Overcoming Practical Barriers to Widespread Societal Adoption…