Researchers develop sensors that can be woven into fabrics

Researchers have developed a shrinkable sensor that can be interlaced into clothes, a development which may pave the path for smart clothing, capable of monitoring human movement.

The embedded microscopic sensor is able to recognize local motion through the stretching of the woven yarns that are treated with graphene nanoplatelets, which can read the body's activity, according to the study published in the Journal of Small.

"Microscopic sensors are changing the way we monitor machines and humans. Combining the shrinking of technology along with improved accuracy, the future is very bright in this area," said, lead researcher of the study, Mina Hoorfar.

This 'shrinking technology' used a phenomenon called piezo-resistivity, an electromechanical response of a material when it is under strain. These tiny sensors have shown a great promise in detecting human movements and can be used for heart rate monitoring or temperature control, explained Hoorfar.

The study showed the potential of a low-cost, sensitive and stretchable yarn sensor. The sensor can be woven into spandex material and then wrapped into a stretchable silicone sheath. This sheath protects the conductive layer against harsh conditions and allows for the creation of washable wearable sensors.

With the idea of smart clothing, fabrics can tell the user when to hydrate, or when to rest. It may change the athletics industry. It can also monitor deformations in fibre-reinforced composite fabrics currently used in advanced industries such as automotive, aerospace and marine manufacturing.

The low-cost stretchable composite sensor has also shown a high sensitivity and can detect small deformations such as yarn stretching as well as out-of-plane deformations at inaccessible places within composite laminates.

The testing indicates that further improvements in its accuracy could be achieved by fine-tuning the sensor's material blend and improving its electrical conductivity and sensitivity. Eventually, this can make it able to capture major flaws like 'fibre wrinkling' during the manufacturing of advanced composite structures such as those currently used in aeroplanes or car bodies.

"Advanced textile composite materials make the most of combining the strengths of different reinforcement materials and patterns with different resin options. Integrating sensor technologies like piezo-resistive sensors made of flexible materials compatible with the host textile reinforcement is becoming a real game-changer in the emerging era of smart manufacturing and current automated industry trends," explained one of the researchers, Professor Abbas Milani.