'Battery-free, quiet, and inherently private' — These 3D-printed metal tags could change home and office tracking, turning penny-sized discs into smart devices using ultrasonic tech for maintenance-free monitoring without charging
Researchers at Georgia Tech have developed battery-free, 3D-printed metal tags that use ultrasonic technology to track everyday actions like opening doors or drawers. The tags generate unique ultrasonic signals when struck by a moving object, with different shapes producing distinct frequencies for identification. These maintenance-free tags offer a quiet, private way to monitor activity without electronics or power sources.
- ▪The metal tags are powered by motion and generate ultrasonic pulses when a moving tab strikes the tag.
- ▪Each tag's unique shape creates a distinct ultrasonic frequency, enabling multiple tags to operate nearby without interference.
- ▪The system relies on external microphones and wearable devices to detect and log the ultrasonic signals for activity recognition.
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| Original publisher | TechRadar |
| Canonical URL | https://www.techradar.com/pro/battery-free-quiet-and-inherently-private-these-3d-printed-metal-tags-could-change-home-and-office-tracking-turning-penny-sized-discs-into-smart-devices-using-ultrasonic-tech-for-maintenance-free-monitoring-without-charging |
| Publication time | Tue, 28 Apr 2026 18:20:00 +0000 |
| Retrieval time | 2026-04-28T18:26:49.538Z |
| Last seen | 2026-04-28T18:26:49.538Z |
| Headline source | Publisher (no WeSearch rewrite) |
| Excerpt source | publisher body |
| Excerpt method | First ~120 words (~800 chars) of extracted publisher body, fair-use limited. |
| Summary | WeSearch · cerebras-chat (WeSearch summarizer) |
| Summary source text | contentText |
| Citation coverage | Summary is a WeSearch-generated derivative; primary citation is the original publisher URL. |
| Cluster | FqClsT9JbrnA |
| Cluster logic | Grouped by semantic title/content similarity across sources within a rolling window. Same-publisher template collisions are excluded from coverage comparison. |
| Ranking reason | Story pages are not engagement-ranked. Hub feeds use recency, with optional source-diversified chronological ordering (cap consecutive stories per source). No personalized ranking. |
| Publisher visit | Yes — open original |
| Substitutes article? | No — link-out required for full text |
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| Indexing | May the item be indexed (stored, ranked, made findable)? | Allowed |
| Snippet | May a short excerpt of the publisher's text be shown? | Allowed |
| AI summary | May WeSearch generate its own short summary of the article? | Limited |
| Retrieval / RAG | May the content be exposed for third-party retrieval-augmented generation? | Not asserted |
| Model training | May the content be used to train AI models? | Not asserted |
| Commercial reuse | May the content be reused commercially? | Not permitted |
Basis: Derived from the published RSS/Atom feed. Contact: [email protected]. Reviewed: 2026-07-24.
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Pro 'Battery-free, quiet, and inherently private' — These 3D-printed metal tags could change home and office tracking, turning penny-sized discs into smart devices using ultrasonic tech for maintenance-free monitoring without charging News By Wayne Williams published 28 April 2026 The tags use ultrasonic sound to record everyday actions When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. (Image credit: Georgia Tech) Copy link Facebook X Whatsapp Reddit Pinterest Flipboard Threads Email Share this article 0 Join the conversation Follow us Add us as a preferred source on Google Newsletter Subscribe to our newsletter Battery-free metal tags generate ultrasonic signals when objects move nearbyDifferent disk shapes create unique sound…
Excerpt limited to ~120 words for fair-use compliance. The full article is at TechRadar.
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