In the 1930s, U.S. Navy researchers stumbled upon the concept of radar when they noticed that a plane flying past a radio tower reflected radio waves. Scientists have now applied that same principle to make the first device that tracks existing Wi-Fi signals to spy on people through walls.

It's tough being a pirate these days. Facing off with foreign navies and missile cruisers on their home turf of the high seas is tough enough for small-arms wielding pirates in diminutive watercraft. Now, the US Navy is bringing in the robots. The Office of Naval Research has plans to imbue its Fire Scout unmanned, ship-launched helicopters with electronic brains capable of identifying the small boats generally used by pirates.

A couple of weeks back we first heard about Octavia, the American Naval Research Lab's (NRL) and Office of Naval Research's (ONR) new firefighting robot designed to perform "shoulder-to-shoulder" firefighting operations with humans aboard Navy vessels. Today we get to see Octavia in action, fighting a simulated fire in a demonstration video that is somewhat less-than-confidence-inspiring.

The US Navy gets around, and its technology has to be versatile, with the ability to deploy in all kinds of terrains, climates, and ecosystems. So the Navy Research Laboratory (or the NRL, but not that NRL) has constructed what Innovation News Daily is describing as the real-life robotic equivalent of the arenas depicted in the sci-fi literary trilogy The Hunger Games: a configurable series of arenas resembling arid deserts, hostile jungle environments, and even oceans in which up to 50 battlefield robots, human soldiers, and other unmanned systems can test their mettle. May the odds be ever in their favour.