If you go down to the woods today you could be in for a big surprise, especially if you're near Boston Dynamics' testing grounds. The robot development company has unleashed its Atlas humanoid robot on the world in outdoor tests.

The 6-foot Atlas humanoid robot was taken out into the woods to test its ability to handle varying terrain. We've already seen videos of the robot walking across rocks, indoors, backed by a support tether. But in this new adventure it appears to be able to make its way outside without overhead support.

While it starts off looking like it's stumbling home after a few too many to drink, even crashing into bushes, it soon gets going. By the end of the video Atlas is running, hunched forward, looking very much like a ninja on a mission.

Boston Dynamics says the Atlas robot works much like humans do when traversing unstable ground. It keeps moving at speed using momentum to help it stay upright.

Moving Atlas outside into unplanned terrain is a big step forward. It doesn't appear to be ready to head out with the military just yet, like its older four-legged Big Dog relative does. It's also still tethered, presumably for controls and power supply. But this could be the future of humanoid robots – so get ready to start seeing that scary gait more in the near future.

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