Several research groups are looking onto wearable sensors and touch activated technologies. The latest news comes from Kansai University, located in Osaka, Japan. The research group has been working on frist generation piezoelectric fabrics.
This type of fabric has a conducting carbon fiber yarn core. Added to this is a piezoelectric polyctric poly-L-lactic acid fiber yarn together with a polyethylene terephthalate middle sheath; and finished with a conducting carbon fiber outer shield. Each of these materials components plays a key function in the connectivity and functionality of the new clothing.
The piezoelectric braided cords produce electrical signals. These signals are generated in response to almost three-dimensional motion. When worn by a person, such mentions could include activities like bending and twisting. Furthermore, the coaxial cable fabrics are interwoven into piezoelectric braided cords. This provides electromagnetic shielding plus high sensitivity. The shielding is necessary so that the clothing will not respond to environmental noise from devices like cells phones. Screening from electromagnetic interference will be important to ensure the technology that forms the clothing works consistently.
According to lead researcher Yoshiro Tajitsu, in conversation with Controlled Environments magazine: “Our research is aimed at developing functional apparel, sometimes referred to as ‘e-textiles’”.
Outlying his future vision, the technologist adds: “We believe that wearable human-machine devices will enable people to interface with external devices naturally, without being limited or hindered by having to perform complicated movements.”
He goes onto explain that ‘e-textiles’ need be comfortable and fashionable. This is necessary if consumers are going to buy the clothes. As a first run, the researchers weaved three types of traditional Japanese decorative knots (Kame, Kicchyo, and Awaji). These produced the types of traditional Kimonos worn by some women in Japan.
Here the type of knot was important, with the most powerful signal produced by Kame and Kicchyo knots. This produce sufficient power and sensor capability to enable a smartphone to take a selfie – simply by twisting the knot of the garment.
As well as fashion, the idea of powered and sensor equipped clothing could be used in the healthcare setting, such as monitoring patient vital signs.
