New 3D-printed gloves could transform the treatment of stroke patients

Aiming to help stroke victims, researchers from the Department of Physics, Indian Institute of Science (IISc.) have developed a flexible, wearable device that harnesses the fundamental properties of light to detect limb movements or of a patient’s fingers. The customizable 3D printed gloves can be controlled remotely, opening up the possibility of tele-consultation by physiotherapists.

According to researchers, stroke is the third leading cause of death in India and the sixth leading cause of disability. Physiotherapy is one of the few treatments available for the rehabilitation of stroke victims and patients with physical injuries, but it can take days or months depending on the severity of the disability, making it difficult for patients and their carers.

“We wanted to develop something affordable and accessible to a person at any time at their convenience. The product should be easy to use and should provide feedback,” said Aveek Bid, associate professor in the Department of Physics, whose team developed the device.

The researchers claim that the stability of the device was tested for more than 10 months and no loss of sensitivity or accuracy was detected. The device has been completely designed and manufactured in India and is expected to cost less than ₹1,000. A patent has been filed and the researchers hope to launch the device on the market soon.

Professor Bid explained that quantifiable feedback – for example, the units of pressure applied when squeezing a ball or the degree of flexion of a leg with a knee injury – is crucial for doctors to monitor the patient, even at distance. Such feedback can also motivate patients to perform better with each consecutive session.

Researchers from the Indian Institute of Science (IISc.) claim that the device was completely designed and manufactured in India and is expected to cost less than ₹1,000. A patent has been filed and the researchers hope to launch the device on the market soon.

Another challenge is that physiotherapy often requires daily hospital visits. Home visits by professionals or sophisticated devices to monitor patients remotely, while ideal, are not readily available and are expensive. To address these challenges, the team developed a mechanism by which customizable garments, such as 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 remotely via the internet and moves your hands and fingers,” according to Professor Bid.

The device can detect various hand and finger movements and accurately detect parameters such as pressure, bending angle and shape.

The technology driving 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 of the patient’s finger or arm causes the flexible material to deform. The deformation modifies the path of the light, and therefore its properties. The device translates this change in light properties into a quantifiable unit. Since the light travels the full length of the device, movement along any part of the patient’s finger or arm can be measured accurately.

“The device is very sensitive – enough to react to the touch of a butterfly,” said team member Abhijit Chandra Roy, DST-Inspire professor in the physics department and mastermind behind the project. “In addition, while existing devices can only detect the flexion of one finger, the new device can even measure the degree of flexion at each finger joint.”

For their device, the researchers used a silicon-based polymer material that was transparent (for easier manipulation of light), soft (for comfort and repeated use) and above all 3D printed. It can be customized to fit each patient’s arm and fingers. The device can capture and store data and transmit it over the Internet, facilitating remote monitoring by clinicians or physiotherapists.