ReWalk Robotics, Ltd. has licensed the Wyss Institute's lower-extremity soft exosuit technology to develop lightweight exoskeleton systems for medical applications such as stroke and multiple sclerosis.
There are an estimated three million stroke patients and 400,000 multiple sclerosis patients in the United States who suffer from limited mobility due to lower limb disabilities. For decades, engineers have been designing and building wearable exoskeletons to help these patients walk again successfully, and to enhance healthy people’s strength and endurance. A number of exoskeletons have been developed recently to achieve these goals, but these systems are generally more suitable for individuals with severe impairments. For those with partial mobility, rigid systems can impede a wearers’ natural joint movements, thus causing fatigue and exacerbating the very problems they are attempting to fix.
The Wyss Institute’s lower-extremity soft exosuit is composed of specially designed clothing-like fabrics that are light, flexible, and do not impede wearers’ motions. Force is applied to targeted areas of the exosuit by small mechanical actuators at precisely the right time in a patient’s walking gait, providing extra support to the muscles as they move. The exosuit is powered by an on-board battery, allowing it to travel unobtrusively with wearers as they go about their daily routines. It can assist the elderly in maintaining or restoring their gait, rehabilitate children and adults with movement disorders due to stroke, multiple sclerosis and Parkinson’s Disease, and reduce the burden on soldiers, firefighters, paramedics, farmers, factory workers, and others with physically demanding jobs.
The first-of-its-kind soft exosuit was developed at the Wyss Institute and the Harvard Biodesign Lab led by Associate Faculty member Conor Walsh, Ph.D. through extensive prototyping that included the involvement of roboticists, mechanical and biomechanical engineers, apparel designers, software engineers, and physical therapists. Throughout its development, the soft exosuit was optimized by insights from continuous research with voluntary study participants, and led to the parallel creation of entirely new forms of functional textiles, flexible power systems, and control strategies that integrate the suit and its wearer in ways that mimic the natural biomechanics of the human body.
By applying assistive force to the wearer’s ankles at the right time during their natural stride, the soft exosuit allows them to walk with greater stability and metabolic efficiency, which could prevent injury and reduce fatigue. It can also be tuned to apply force to “retrain” the gait of someone who has adopted uneven walking movements to compensate for reduced mobility due to injury or disease.
In 2016, the Wyss Institute partnered with ReWalk Robotics in a collaboration to accelerate the development of its soft exosuit technology for assisting people with lower limb disabilities caused by stroke or multiple sclerosis, bringing together the Institute’s technical innovation and ReWalk’s expertise in the commercialization of wearable robotics. ReWalk also licensed the lower-extremity soft exosuit technology from Harvard University as part of the agreement, and licensed additional related technology in 2019.
The same year, ReWalk obtained a CE mark for their commercialized version of the soft exosuit, called the ReStore™, clearing it for sale to rehabilitation clinics in the European Union. Days later, it received clearance from the FDA for sale to rehabilitation centers across the United States for use in the treatment of stroke survivors with mobility challenges, making ReStore™ the only soft exosuit with FDA clearance. In 2020, the US Centers for Medicare and Medicaid Services issued a Healthcare Common Procedure Coding System (HCPCS) Level II Code in response to ReWalk’s application, establishing the first code to facilitate insurance claims for medical exoskeletons.
In addition to the lower-extremity soft exosuit for ankle support, the Wyss Institute has developed models that assist other joints including the hip and knee. The team is continuing to develop soft exosuits that improve the mobility of the upper extremities as well, including the shoulder and hand.