Researchers from the Ohio State University have sewn electronic circuits into a fabric with 0.1 millimetre precision. According to them, this is a closer step toward manufacturing clothes with computer components that can gather, store or transfer data.
“A revolution is happening in the textile industry,” explains John Volakis, director of the ElectroScience Laboratory at Ohio State. “We believe that functional textiles are an enabling technology for communications and sensing — and one day even medical applications like imaging and health monitoring.”
The study published in the journal IEEE Antennas and Wireless Propagation Letters involved creating the functional textiles or as they call it “e-textiles” on a conventional sewing machine. Instead of using a regular thread, the researchers replaced it with fine silver metal wires embroidered by the sewing machine based on the pattern of the computer file.
The metal thread is 0.1-mm in diameter contains seven filaments. The filaments are made of copper and coated with pure silver. Apparently, these metal wires feel like the real threads upon touch.
“We started with a technology that is very well known–machine embroidery–and we asked, how can we functionalise embroidered shapes? How do we make them transmit signals at useful frequencies, like for cell phones or health sensors?” adds Volakis. “Now, for the first time, we’ve achieved the accuracy of printed metal circuit boards, so our new goal is to take advantage of the precision to incorporate receivers and other electronic components.”
The shape of the embroidery determines the frequency of operation of the antenna or circuit, with one consisting of six interlocking shapes that made it look like tiny circles. Based on their tests, the antennas have frequencies of 1 to 5 GHz, suggesting that it can be used for cell phone and internet access.
“Shape determines function,” Asimina Kiourti adds. “And you never really know what shape you will need from one application to the next. So we wanted to have a technology that could embroider any shape for any application.”