MIT, Caltech researchers each develop wearable biosensors to monitor vital signs
A group of researchers from MIT have embedded biometric sensors into fabric to make clothes that can remotely monitor temperature, breathing, heart rate and other vital signs in patients, athletes and astronauts, writes MIT News.
The fabric fits any body type, is machine washable, and the sensors can be removed and embedded on a different piece of clothing. The fabric is described in a paper written by Canan Dagdeviren, the LG Electronics Career Development Assistant Professor of Media Arts and Sciences at MIT. The study was led by MIT graduate student Irmandy Wicaksono, and had many contributions by undergraduate students.
“We can have any commercially available electronic parts or custom lab-made electronics embedded within the textiles that we wear every day, creating conformable garments,” says Dagdeviren. “These are customizable, so we can make garments for anyone who needs to have some physical data from their body like temperature, respiration rate, and so forth.”
The group wanted to develop technology for clothes people would wear on a daily basis, with electronic sensors wrapped in epoxy and woven into the fabric to be in contact with the skin. The prototype shirt created for the study has 30 temperature sensors, an accelerometer, and is made of a polyester blend. The data is then sent to a smartphone. The sensors can be seen on the inside layer of the shirt, but are not visible from the outside.
“In our case, the textile is not electrically functional. It’s just a passive element of our garment so that you can wear the devices comfortably and conformably during your daily activities,” Dagdeviren says. “Our main goal was to measure the physical activity of the body in terms of temperature, respiration, acceleration, all from the same body part, without requiring any fixture or any tape.”
The shirt prototypes were tested at the gym, and future plans include integrating the sensors with pants and other clothes to monitor blood oxygen levels. Dagdeviren argues the technology could be used in telemedicine, making it easy for doctors to monitor their patients remotely. The project was funded by the MIT Media Lab Consortium and a NASA Translational Research Institute for Space Health Seed Grant from the MIT Media Lab Space Exploration Initiative.
On the other side of the country, a team from Caltech has figured out how to use human sweat to provide the power, which was once an obstacle, for electronic skin that sends biometric information via Bluetooth, says All About Circuits. E-skin is worn on top of human skin to collect information such as blood pressure and heart rate.
The necessity for close proximity when battery-free e-skin transmits data over NFC, human motion and battery inefficiency for long-term use were some of the challenges the team had to solve, but according to Wei Gao, an assistant professor in the Andrew and Peggy Cherng Department of Medical Engineering, a perspiration-powered electronic skin (PPES) could solve these problems by turning lactate into electricity.
“Bluetooth communication consumes higher power but is a more attractive approach with extended connectivity for practical medical and robotic applications,” explains Dr. Gao.
The e-skin is made of rubber that has sensors to monitor body temperature, heart rate, or blood sugar levels. The current prototype tracks glucose, urea, NH4+, and pH.
“In addition to being a wearable biosensor, this can be a human-machine interface,” Dr. Gao says. “The vital signs and molecular information collected using this platform could be used to design and optimize next-generation prosthetics.”