Google researchers control music playback by tapping a braided cable
Those who prefer cabled rather than wireless headphones or earphones will likely be very familiar with a little control box positioned somewhere along the audio cord that's used to control playback or take calls. Google researchers have now come up with a textile-covered cable that can pause play with a tap, skip tracks with a double-tap and control volume with a twist.
The cable is wrapped in a so-called e-textile braid that's reported capable of detecting a user's proximity, touch and twist. This is thanks to electrically insulated conductive yarns woven in opposite directions for send and receive functionality, and braided together with strands of passive yarn. The repeating pattern of the braids allows for touch gesture support along the length of the cable, and visual feedback can also be achieved by incorporating fiber optics into the weave.
A small group of volunteers was recruited to interact with the smart cable, and asked to perform eight gestures in their own style. A machine learning model was then trained on the resulting data so that the I/O braid could distinguish between swipes, slides, pinches, grabs, squeezes and twists – achieving a gesture recognition accuracy of 94 percent.
The researchers then devised a single operation study to compare user interactions with the braided cable, a multi-touch trackpad and a headphone cord with inline control buttons. The team found that users not only preferred using the e-textile cable, but the interactive cord proved faster than using inline buttons controls and about the same speed as a touch surface.
Though the team doesn't appear to have any desire to incorporate the technology into consumer products itself, it did go on to develop three e-textile prototypes for demonstration purposes – a braided USB-C headphone cable to control media playback on a phone, a hoodie drawstring to add invisible music control to clothing, and a cord for smart speakers that supports gesture control.
The research has been published in the Proceedings of ACM CHI 2020. The video below has more.