Engineers have developed a way to incorporate electronic sensors into stretchy fabrics, potentially allowing clothes to monitor vital signs.

MIT researchers have been creating sensor-embedded garments, which are machine washable, that fit close to the body of the person wearing them. The researchers envision that this type of sensing could be used for monitoring people who are ill, either at home or in the hospital, as well as athletes or astronauts.

Previous studies have come up with thin, skin-like patches that can measure temperature and other vital signs, but these are delicate and must be taped to the skin.

MIT researcher Canan Dagdeviren set out to create garments more similar to the clothes we normally wear, using a stretchy fabric that has removable electronic sensors incorporated into it.

“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,” Dr 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 electronic sensors consist of long, flexible strips that are encased in epoxy and then woven into narrow channels in the fabric. These channels have small openings that allow the sensors to be exposed to the skin.

Researchers have designed a prototype shirt with 30 temperature sensors and an accelerometer that can measure the wearer's movement, heart rate, and breathing rate. The garment can then transmit this data wirelessly to a smartphone.

The researchers chose their fabric -- a polyester blend -- for its moisture-wicking properties and its ability to conform to the skin, similar to compression shirts worn during exercise.

“From the outside it looks like a normal T-shirt, but from the inside, you can see the electronic parts which are touching your skin,” Dr Dagdeviren says.

“It compresses on your body, and the active parts of the sensors are exposed to the skin.”

The garments can be washed with the sensors embedded in them, and the sensors can also be removed and transferred to a different garment.

Their latest report is accessible here.