How do Cloaking Devices Work?

<p>When an object, such as an aircraft or submarine, moves through a fluid it generates a 'wake' behind it which can be used by monitoring tools to detect its size and position. Cloaking devices work by modifying this wake to hide the object from detection, or to provide false information about its size and intention. Sam Shelley, a researcher at the University of Exeter, explains how a flexible tail can be fixed to the back of an object to modify its wake for this purpose, or even to generate energy harvesting in the ocean. </p> <p>Research by Sam Shelley at the University of Exeter. </p>