Imagine toddlers with brain injuries or cerebral palsy trying to crawl. If they are unable to crawl, then eventually they will not be able to stand up, balance themselves, walk or run. Others such as lower limb amputees, people with multiple sclerosis, hemiplegia and the elderly also have restricted mobility. Biomechanics is helping design lower limb suits for these toddlers and individuals to improve their mobility. Biomechanics is the study of the interplay between our joints, muscles and nervous system resulting in patterns of movement and in the alignment of our body vis-a-vis the environment and gravity. It is now spearheading a new revolution in designing wearable prosthetics.
“Biomechanics suit” – the word conjures up images of Iron man and his robotic, rigid suit. Earlier these suits were made of rigid materials such as metals and plastic. Users found it difficult to wear them and often discarded them. But times are changing. Modern day biomechanics suits are called “exoskeletons” or “super suits”. These are made of spandex and soft, breathable and flexible materials making them light and comfortable.
Several researchers at Harvard’s Wyss Institute, University of Delaware and University of Massachusetts have been working to overcome the problems associated with the older generation of rigid and cumbersome heavy suits. Michele Lobo, assistant professor of physical therapy at the University of Delaware has created several exoskeletons or Super Suits. Playskin Lift is one such comfortable exoskeletal garment for children with disabilities. It is an anti-gravity suit made of soft stretchable spandex with mechanical inserts made of piano wires and a trunk brace which help lift and support the child. Other researchers at the University of Delaware are designing a fine vibrating shoe to help patients with Parkinson’s disease maintain their balance and walk faster.
Harvard’s Wyss Institute researchers in collaboration with ReWalk Robotics, are designing an “exosuit” made of soft fabric with powerful hidden actuators inside the belt to assist users with lower limb disabilities to move with greater stability and feel less fatigued.
With the help of the science of mechatronics, robotics and kinesealogy (study of movements), researchers at the University of Massachusetts have created their first prototype for below knee and above ankle amputees. This prototype has two new features which are expected to improve psychological and physical problems of amputees while adapting to the prosthetics. The features include extending the gait cycle of the robotic leg and injecting power into it while reducing the power distribution within the socket of the lower leg.
These are a few examples of how understanding the mechanics of the human body is helping researchers design wearable robotic technology which in turn is helping to rehabilitate and improve mobility of individuals with disabilities.