With an aim to help rehabilitation of stroke victims and patients requiring physiotherapy, researchers at the Indian Institute of Science (IISc) have designed a soft, wearable device that exploits the fundamental properties of light to sense a patient's limb or finger movements
Stroke is India’s third leading cause of death and the sixth leading cause of disability. Physiotherapy is one of the few treatments available for rehabilitating stroke victims and patients with physical injuries. However, physiotherapy can take days to months depending on the severity of the disability, making it challenging for patients as well as their attendants.
The device developed by the IISc researchers exploits the fundamental properties of light to sense a patient’s limb or finger movements. The customisable, 3D printed gloves can be remotely controlled, opening up the possibility of teleconsultation by physiotherapists.
“We wanted to develop something affordable, and available to a person at all times at their convenience. The product should be easy to use and must provide feedback,” says Aveek Bid, Associate Professor at the Department of Physics, whose team has developed the device.
The team has also developed a mechanism by which customisable wearables like hand gloves can be designed, 3D printed, and controlled remotely.
“The idea behind the device is that you wear something like a glove, the physiotherapist controls the device from a remote location through the internet, and makes your hands and fingers move,” describes Bid.? The device can sense various hand and finger movements, and precisely detect parameters like pressure, bending angle and shape.
The technology that drives the device is based on the fundamental properties of light: refraction and reflection. A light source is placed at one end of a transparent rubbery material, and the other end has a light detector. Any movement in the finger or arm of the patient causes the flexible material to deform. The deformation alters the path of light, and thereby its properties. The device translates this change in light properties to a quantifiable unit. Since light travels across the entire length of the device, movement along any part of the patient’s finger or arm can be accurately measured.