A group of researchers at Harvard is developing a soft exosuit and have some very high hopes for their high-tech mobility aid. The Wyss Institute for Biologically Inspired Engineering at Harvard University entered into a collaboration last year with ReWalk Robotics Ltd., to accelerate the development of its exosuit technologies for assisting people with lower limb disabilities.
The exosuit, made of soft, comfortable, lightweight fabrics, is essentially a wearable robot that could one day help sufferers of strokes, multiple sclerosis, Parkinson’s disease, and potentially even healthy soldiers that carry heavy loads, allowing them to move with more freedom.
In order to move forward with their design, however, the team needs to quantify how much energy exactly the suit is capable of saving. Recently the team made a step in the right direction toward their lofty goal by isolating the suit’s load-bearing benefits and determining that a tethered version can result in energy savings of almost 23 percent.
Developed at Harvard’s Wyss Institute, and unlike most suits we’ve seen in the past, the soft exosuit is designed for people that can already walk on their own but may need assistance due to conditions that impact their mobility. The system consists of functional textiles, cable-based actuation, and a control system that takes its cues from the user’s individual walking mechanics and provides assistance to specific leg joints, rather than the entire limb.
During testing on healthy subjects, the researchers noticed that the more assistance provided to the ankle joints, the more energy the wearers could save with a maximum reduction of almost 23 percent compared to walking with the exosuit powered off. To date, this is the highest relative reduction in energy expenditure observed with a tethered exoskeleton or exosuit.
While this configuration doesn’t represent how the researchers imagine wearers will eventually use the suit, understanding the response of healthy individuals is the first step towards developing these devices for individuals with gait impairments. Once the team understands how the system performs on healthy subjects, the better they will be able understand how they perform on individuals with gait impairments.
So where do they go from here? The team will now look to perform studies that explore the energy-saving effects with a full-body version of the exosuit where the weight is carried by the user.
