Something very strange happened in the R&D lab of a UK-based electronics engineering company. A research team at Roke Manor Research was working on text-based radio frequency systems when a team member suddenly detected a signal—coming from a random bag of components off to the side. A small movement had apparently turned mechanical energy into electrical energy within the bag. After figuring out how this phenomena occurred, a Roke team subsequently harnessed it and created a new tiny tracking device. Their invention works over a greater distance than most existing tags, and here’s the killer quality that makes it really different from nearly all tracking devices: It works without batteries. The device is called Agitate and it’s a self-charging miniature device, no larger than a quarter. The agitate tag’s signal “can be tracked through walls and up to 20 kilometres in built-up areas, ” writes the company, “with an estimated range of 200 kilometres in free space.” So how does it work? Basically Agitate is made of two plates, one is metal and the other a charged material. When either of the two plates are moved, even just slightly, mechanical energy is turned into electrical and is used to transmit a radio pulse. The signal only lasts a few seconds but is more powerful than a cell phone. And it’s very precise—the shorter the radio pulse, the more precise the signal to a specific location. (more…)        

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Accidental Discovery Leads to Tiny, Battery-Free Tracking Device