Frequent readers know that we’re always on the lookout for technology that’s compatible with fabrics and clothing. Researchers at North Carolina State University have produced an antenna that can be stretched or rolled, enabling wearable sensors to better communicate with remove devices.
We heard a lot about printing silver nanowires onto fabric at the Flexible Electronics conference a couple of months ago. Antennas, however, are even trickier because their shape determines the frequency and bandwidth at which they transmit. Deform the antenna and the frequency changes, which brings down the communications link.
What the scientists at NCSU have done, said senior author Dr. Yong Zhu, is two-fold: find a technique that will let the antenna return to its original shape after being deformed, and discover that the frequency changes can be controlled. Silver nanowires are sprayed in the desired pattern to make an antenna; the wiring is covered with a plastic polymer, and the whole thing is put on a ground layer of the polymer, this time with a continuous layer of silver nanowires.
In addition, the antenna can act as a stress gauge, because the relationship between deformity and frequency change turns out to be pretty linear.
The full paper is here, but is behind a paywall.