An element of jeans clothes. A seam of yellow thread. Back pocket.

More than it seams: conductive yarn tracks body motion

Image credit: Rustam Ziabirov/Dreamstime

A new study has found that conductive seams, when strategically placed in clothing, can accurately track body motion.

According to computer scientists at the University of Bath, such charged seams can respond to subtle movements that aren’t picked up by popular fitness trackers, such as watches and wristbands. And in the study, they found that clothing made with conductive seams can be analysed to identify the wearer’s movements.

“There are lots of potential applications for conductive yarn in any activity where you want to identify and improve the quality of a person’s movement,” said PhD student Olivia Ruston at Bath. “This could be very helpful in physiotherapy, rehabilitation, and sports performance.”

A garment sewn with conductive yarn, with seams connected by wire to a microcontroller

As part of the study, the team connected the seams to a microcontroller, and then a computer, where it recorded the voltage signal.

Image credit: Olivia Ruston

Groups of scientists have been creating flexible textile sensors for garments for some time, but the Bath project is the first where researchers have experimented with the location and concentration of conductive seams. They found that where seams are placed on a garment, and the number of seams that are added, are important considerations in the design of a movement-tracking smart garment.

“There’s great potential to exploit the wearing of clothing and tech – many people are experimenting with e-textiles,” Ruston explained, “but we don’t have a coherent understanding between technologists and fashion designers, and we need to link these groups up so we can come up with the best ideas for embedding tech into clothing.”

The yarn used by Ruston and her team has a conductive core that is a hybrid metal-polymer resistive material intended for stretch and pressure sensing. Once incorporated into a garment’s seam, it is activated at low voltages. The yarn's resistance fluctuates as body movement varies the tension across the seams.

In the study, the seams were connected to a microcontroller, and then a computer, where the voltage signal was recorded.

Professor Mike Fraser, co-author and head of computer science at Bath, said: “Our work provides implications for sensing-driven clothing design. As opportunities for novel clothing functionality emerge, we believe intelligent seam placement will play a key role in influencing design and manufacturing processes. Ultimately, this could influence what is considered fashionable.”

Sign up to the E&T News e-mail to get great stories like this delivered to your inbox every day.

Recent articles