The proof of concept of ‘Exosuit’ that is a wearable robot made of functional textiles, cable-based actuation, and a biologically-inspired control system was given in 2016 by the researchers at Harvard Wyss Institute. They directly target the ankle joints. The researchers have been working on a soft Exosuit for years and a recent study has revealed now that how much the suit can actually benefit its wearer.
The Harvard’s Exosuit decreases the energy a user requires to exercise during walking by 23 percent, as per a new study published as a cover article in ‘Science Robotics’. Seven healthy wearers formed the test group. The objective of the Exosuit is to offer help to people who carry heavy loads and for the disabled people by targeting specific leg joints.
The impact on wearer’s joints was estimated by the researchers with light wearable textiles and pulling cables. Furthermore, they removed the actuation, electronics and battery units.
It was discovered that the wearers significantly adapted their pace with increasing levels of assistance. But, the most substantial changes were at the ankle joint and at the hip owing to the additional straps coupling from back of the lower legs to the front of the hip.
The multi-faceted study was backed by the Wyss Institute for Biologically Inspired Engineering, the Harvard John A. Paulson School of Engineering and Applied Sciences in addition to the Defense Advanced Research Projects Agency (DARPA)’s Warrior Web Program, the National Science Foundation, a Samsung Scholarship, the São Paulo Research Foundation and the Robert Bosch Stiftung.
John L. Loeb, Associate Professor of Engineering and Applied Sciences at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) and the Founder of the Harvard Biodesign Lab accompanied by Conor Walsh,a Wyss Institute Core Faculty member, lead the team.
“In a test group of seven healthy wearers, we clearly noticed that the more assistance provided to the ankle joints, the more energy the wearers could save with a maximum reduction of nearly 23% compared to walking with the exosuit powered-off. To our knowledge, this is the highest relative reduction in energy expenditure observed to date with a bound exoskeleton or exosuit.”
According to Brendan Quinlivan, a graduate student who is working with Walsh and one of the first two authors on the study:
“Other studies had stated that there can be an energy transfer between the ankle and other joints. However, by having a textile connect the ankle and hip with our soft exosuit, may have amplified this effect, providing to the considerable energy savings we found.”
Moreover, further studies are required in order to compare the effects of fully body-worn versions, as per the authors. These studies quantify the impact of technology as the wearer carries the weight of the actuation and battery.
When compared to a conventional exoskeleton, there are numerous benefits of the Exosuit. The worn part of the suit is exceptionally light. Besides, the wearer’s joints are unhindered by external rigid structures. Thus, the suit would have a minimum unintentional interference with the body’s natural biomechanics.
Another graduate student in Walsh’s team and a co-first author of the study, Sangjun Lee stated:
“The results from this research will help us find a sweet spot between the added system weight and the amount of force applied to achieve maximum benefits in energy expenditure in wearers. Defining these interdependencies in healthy people will eventually also help us design versions suitable for people with walking abnormalities.”
Donald Ingber, M.D., Ph.D., is the Founding Director of Wyss Institute. He is also the Judah Folkman Professor of Vascular Biology at Harvard Medical School and Professor of Bioengineering at Harvard SEAS. He said in a statement:
“This study represents another major step forward along a path that will bring this new type of ‘wearable robot’ into the market where it will help soldiers and workers, as well as patients with disabilities.”
Check out the way the robot makes life simpler: