We've seen a variety of "smart clothes" over the years, with most generally functioning like wearable fitness trackers, packed with sensing equipment to capture a variety of biometric data. Researchers in Canada have focused instead on creating a smart T-shirt with the potential to help diagnose respiratory illnesses or for real-time monitoring of respiratory rates for people with conditions such as asthma, sleep apnea or chronic obstructive pulmonary disease (COPD).
The challenge for the researchers at Université Laval's Faculty of Science and Engineering and its Center for Optics, Photonics, and Lasers, was creating a smart T-shirt that operates without any wires, electrodes or sensors needing to come into direct contact with the wearer's body.
To achieve this, they embedded the T-shirt with an antenna made of a hollow optical fiber coated with a thin layer of silver that sits at chest level. The antenna acts as both a sensor and a transmitter, collecting and transmitting data on the body's respiratory movements. With each breath, the smart fiber tracks thorax circumference and the volume of air in the lungs.
"These changes modify some of the resonant frequency of the antenna," explains Professor Younes Messaddeq, whose team developed the technology. "That's why the T-shirt doesn't need to be tight or in direct contact with the wearer's skin. The oscillations that occur with each breath are enough for the fiber to sense the user's respiratory rate."
The idea is that the smart T-shirt would transmit its data in real time to a smartphone or computer, allowing the monitoring of respiratory patterns that could help diagnose certain illnesses. The technology also can work as a real-time monitor, potentially allowing alarms to be triggered for those who suffer from irregular respiration while they sleep.
Because the smart fiber is light and can be innocuously sown into a regular garment, Messaddeq notes that it doesn't inhibit natural movements and offers reliable data regardless of whether the wearer is lying down, standing, moving or sitting.
Another major benefit is that the garment can be washed in a regular way without damaging any of the internal components as the smart fiber's surface is covered in a polymer that allows it to withstand to rigors of being run through a washing machine without any problems.
The technology is still in the early stages, but the team foresee it being incorporated into a variety of garments for applications such as patient monitoring in hospitals or nursing homes.
The team's research was published in the journal Sensors.
Source: Université Laval (French)
