For decades, robots have been being built that are increasingly capable and lifelike, but for the most part, it’s always been easy to differentiate a robot from a person.  Their clunky movements, inability to navigate varied terrain, and the whirring of servos and electric motors tends to make it pretty easy to tell the difference between an early model terminator and your friend Randy that you talk “Game of Thrones” with at the water cooler.

Of course, as militaries around the world continue to work toward creating more autonomous solutions to the age old problems of war, it’s only a matter of time before the line starts to get a bit blurry.

Like with Petman, the Boston Dynamics robot designed to test chemical and biological suits for the U.S. military.  The robot actually produces a lifelike environment inside the suit, while monitoring in real time to detect any chemicals that manage to leak through it.  The robot’s skin, beneath its protective suit, even sweats to ensure the suit can be tested in close to real circumstances, without risking the safety of a human being.

The result?  A terrifyingly lifelike human facsimile, complete with sweaty armpits and tellingly clenched fists.