Stretchable speaker/mic

Sensors and transducers are a necessary component for for wearables and other Internet-of-Things devices - creating one that can stretch has been a goal for many trying to incorporate this technology into fabrics.

Korean scientists have just published their research on a stretchable speaker (that can also be used as a microphone) for use in wearables.stretchable.jpg

The transducer that they call a "Stretchable Acoustic Device" (SAD) uses a liquid metal coil, fabricated by injecting galinstan (an alloy of gallim, indium and tin) into an elastic form with a powerful neodymium magnet.

The speaker/mic could be sewed into clothing or applied to backpacks, hats, gloves, flexible phones, etc. In addition to traditional acoustic signal use, it could also be used for sensing biological signals (say a heartbeat or muscle contractions) or in hearing aid systems.

Here’s a link to the research paper and a video that shows the speaker/mic in action.

Interesting stuff!