Battery-free smart tags for smarter homes

Researchers at Georgia Institute of Technology have developed tiny, battery-free metal tags that could transform how smart homes track everyday activity. The tags, smaller than a coin and costing just a few rupees each, emit unique ultrasonic signals when triggered by motion such as opening a door or drawer. Each tag produces a distinct frequency based on its shape, allowing wearable devices to identify specific actions without relying on cameras or microphones. The system offers a more private alternative to traditional smart home sensors. Led by PhD student Yibo Fu, the team says the tags could monitor water use, assist elderly care, or even track gym exercises. Early prototypes have potential applications ranging from libraries to large-scale waste management systems.

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