Everyone, say hello to WildCat, a robotic quadruped that can run 16 mph (26 kph) without tethers. It joins an already impressive cast of conceptual bots, including an updated version of ATLAS — who, as showcased in a must-see new video, may soon appear on an episode of American Ninja.

Indeed, the Pentagon's robotic army is coming together rather nicely. Thanks in most part to the work being done by the DARPA-funded Boston Dynamics, we've got two humanoid robots, ATLAS and Petman, a robotic Cheetah, BigDog, and a soon-to-be bulletproof mechanized pack mule. I'm trying to imagine a scenario in which all of these could be used together. Perhaps you guys can come up with your own ideas and add to comments.

WildCat is the latest addition to the family — a rugged, free-running bot that DARPA hopes will someday reach speeds of 50 mph on "all types of terrain." WildCat can currently run on flat ground using bounding and galloping gaits.

It looks like a souped-up version of BigDog, and that's probably not a coincidence; they both appear to be fitted with the same chassis and fuelled by a petrol engine. The idea behind a robotic quadruped, aside from it being a conceptual technological advance, is that it'll eventually be used to run supplies to the frontline or other dangerous areas, but it's anyone's guess as to what it'll eventually be made to do.

And now check out this latest video of ATLAS at work — and holy crap is Boston Dynamics making great strides with this thing:

It shows ATLAS walking — and practically tip-toeing — across uneven rocky terrain, while also having to retain its balance when being struck by a heavily weighted object.