Part 1 of 2, Physical AI: The DARPA Legacy & the Road Ahead. What the DARPA Robotics Challenge Actually Built—and Why It Still Matters In March 2011, a massive earthquake and tsunami triggered a nuclear disaster at the Fukushima Daiichi power plant in Japan. Radiation and structural damage made parts of the facility too dangerous for people to enter, yet the available robots could do little more than observe from a distance.