Years before Lucasfilm created the AT-AT and Boston Dynamic's Big Dog terrified the world, the US Army was working with General Electric on the "Walking Truck" project, basically a large walker which was controlled by a lever-pushing operator.
Called the Cybernetic Anthropomorphous Machine (or CAM for short), the walker may not have been used by the US Army in combat on rough terrains, but the idea was certainly explored by them in the early '60s, as the video here shows.
Unlike the AT-AT walkers, a human had to actually sit in the CAM and control the walker using hydraulic levers. Its strength seems pretty high, considering it can kick a small Jeep aside with ease, but according to the video it was possible to be gentle too, with the operator able to feel the resistance when the walker's foot was touching an object.
At the time the video was filmed, the CAM was sitting in an Army warehouse in Detroit somewhere, but it appears to have been painted red along the way, and is now on show at the US Army Transportation Museum at Fort Eustis. There's something rather spooky hearing that "the technology that went into its creation is available for future applications," and that back then they believed "the interfacing of this technology with a more advanced one will bring us that much closer to the realization of a mechanical man." Just 10 years later, Lucas showed the AT-ATs to the world, and thirty years after that, the Big Dog was born. What more can we expect from quadruped robots in the future, I wonder? [CyberneticZoo via VideoSift via Technabob]