Wearable sticker converts hand movements into communication

The new wearable sticker is made from polydimethylsiloxane (PDMS), a type of silicone elastomer that is very flexible and skin friendly.

To give the patch its movement-sensing capability, the researchers embedded the PDMS with fibre Bragg grating (FBG), a type of reflector that is etched into a short segment of optical fibre to reflect specific wavelengths while transmitting all the others.

Researchers said the sensor makes it possible to detect slight changes in the way light propagates through the fibre optic during movement, allowing the system to detect specific movements by analysing the alterations in light behaviour.

In a statement, Kun Xiao from Beijing Normal University in China, said: “For someone recovering from a stroke, these sensors could monitor wrist, finger or even facial movements to monitor their rehabilitation progression.

“For individuals with severe mobility or speech impairments, the sensors could translate gestures or facial expressions into words or commands, enabling them to communicate with others or interact with technology more easily.”

The researchers also developed a precise calibration method that allows the sensors to be tailored to each user, making them adaptable to various applications.

“Beyond detecting movement, these adaptable sensors could be tailored for applications such as monitoring other health indicators like respiratory or heart rate by detecting subtle body movements,” said Rui Min from Beijing Normal University.

“They could also be useful for athletes or fitness enthusiasts to monitor and improve their form or technique in real-time or be integrated into gaming systems for more immersive and interactive experiences.”

To demonstrate the capabilities of their PDMS-embedded wearable FBG sensors, the researchers conducted a series of tests focusing on gesture recognition and communication assistance.

After calibrating the sensors for individual participants, they attached the sensors to different parts of the body, such as the wrist and fingers, to detect various movements. They also developed a system that enabled the sensors to translate simple gestures into commands or messages, using finger movements to spell out words based on Morse code, for instance.

For both tests, the sensors demonstrated a ‘high level’ of sensitivity and accuracy in recognising a wide range of gestures, as they could detect subtle movements that might be difficult for some traditional sensors to pick up.

In the communication assistance experiment, the sensors successfully translated gestures into words, showing their potential as an assistive technology for individuals with speech or mobility impairments.

This research is part of a larger project aimed at developing innovative assistive technologies and was inspired by the challenges faced by people with disabilities and those recovering from conditions like strokes, who often struggle with basic movements and communication.

“Traditional methods are either too cumbersome, lacked accuracy or weren't versatile enough to cater to individual needs,” said Zhuo Wang from Beijing Normal University. “Our goal was to develop a wearable solution that was both precise in detecting gestures and comfortable for everyday use, offering a more personalised and adaptive approach to rehabilitation and assistance.”

The researchers are now working to improve and refine the technology to make it available for practical use and further clinical trials, looking to make the sensor system even smaller and more integrated and enhancing the sensors' ability to communicate wirelessly with smartphones, computers or medical devices.

The research paper, published in Biomedical Optics Express, can be read in full here.