People suffering from ALS (amyotrophic lateral sclerosis) often have difficulty raising their arms, due to deterioration of cells in their brain and spinal cord. A new wearable system is designed to help, utilizing a pair of under-arm balloons.
Created by a team of scientists at Harvard University and Massachusetts General Hospital, the halter-type setup incorporates two Y-shaped soft-robotic actuators, located under each of the wearer's armpits. Hoses connect both fabric-bodied actuators to a battery-powered air pump, mounted on the back of the user's waist.
When integrated sensors detect the slight residual upward arm movements which the wearer is still able to manage on their own, those sensors trigger the pump to inflate the corresponding actuator, thus smoothly and gently lifting the arm. Making a slight downward muscle movement likewise triggers the actuators to deflate, lowering the arm down again.
The system has already been tested on 10 ALS patients. A 30-second calibration process was initially required to gauge each user's distinct level of arm/shoulder strength and mobility. All of the participants subsequently learned to use the setup in less than 15 minutes, successfully performing tasks such as reaching for and holding up objects.
Given the fact that ALS typically progresses to the point that even slight muscle movements are impossible, the scientists are now looking into methods of triggering the actuators using nothing but brain signals. These would be detected by a wearable brain-computer interface.
"This study gives us hope that soft robotic wearable technology might help us develop new devices capable of restoring functional limb abilities in people with ALS and other diseases that rob patients of their mobility," said Prof. Conor Walsh, senior author of a paper on the research.
That paper was recently published in the journal Science Translational Medicine.
Source: Harvard John A. Paulson School of Engineering and Applied Sciences