A self-charging miniaturised radio signalling device with a 200km range developed by accident could help save lives at sea.
Researchers at Roke, a Chemring Group company, have developed AGITATE – currently the size of a five pence piece – which requires no battery as shaking it converts mechanical energy into radio pulses, like a dynamo that uses mechanical energy to power bicycle lights.
A small dielectric is charged, and when shaken the tag generates a radio signal that can be tracked through walls and up to 20km in built-up areas, with an estimated range of 200km in free space.
Peter Lockhart, future technology manager for Roke, says: "As with many of the best inventions, AGITATE was developed by accident. But thanks to their highly inventive and creative minds, they recognised a potential application and have brought that to fruition, developing a simple yet highly usable technology.”
Roke's research and design team anticipate that AGITATE could be produced for a few pence per unit and would have a broad range of tracking applications.
Potential uses might include a low cost method of monitoring and regulating the use of lifejackets, with built in man-overboard capability, or remote sensing for flood monitoring and alerts.
In the industrial sector it could be used for remote sensing of motion and vibration fault detection in harsh environments; in the retail sector as security tags on high-value goods or in the healthcare sector for keeping track of patients, such as those suffering from dementia.
The research and development team has already completed UK trials across 26km of variable terrain. Further Roke investment is focussed on reducing AGITATE's footprint and increasing RF output power even further.