SINGIN', HEY DIDDLE DIDDLE:

The specific inspiration for the DARPA Robotics Challenge came in dramatic circumstances, when an earthquake struck off the coast of Japan in March 2011. Attempts at cleaning up the damaged nuclear reactor at Fukishima highlighted the limitations of the best existing robots and showed the need for machines that can better navigate the human world. DARPA devised its challenge to inspire robots that could help should such a situation occur again. The robots must be able not only to work in environments designed for humans but also to navigate those sites after they are severely damaged.

Atlas performed well in Miami, but it is a long way from perfect. For one thing, the power needed to drive its hydraulic systems limits its usefulness. The robots deployed in the contest each required external generators to power their hydraulics; the generators are too large to carry, relatively inefficient, and loud. Even though future versions of Atlas are meant to carry their own power source, this will still be a rudimentary solution until researchers can figure how to make the machines far more energy efficient.

Perception is another big challenge. Atlas uses dynamic balance, and it can scan its surroundings for obstacles, but the way it uses this information to navigate is still slow and crude. "If you watch someone dancing or climbing or doing parkour, we are incredibly far [away from] a robot that can do that," Pratt says.

During the DARPA challenge, Atlas operated partly autonomously, in that teams could provide specific instructions and command it to perform a task, but much of the robot's behavior, including its split-second rebalancing, happened automatically. DARPA's vision is for rescue robots to operate this way, with humans providing guidance and assistance but the robots functioning autonomously when needed, such as when a communications link fails. But if robots are ever to perform the kinds of tasks that some envision--such as helping the elderly in the home--they will need to have the ability to work with even greater autonomy.

Back in the pit lane, near a garage commandeered by a support team from Boston Dynamics, Raibert says humans and animals have extraordinary mobility, more than any human-made vehicle, so it makes sense to make robots with legs. "Let me just say I think the future of robotics has got to go there," he says, just before one of his robots starts walking assuredly over a pile of rubble. "You can do stuff now without it, but eventually you're really going to want that, and that's what we're hoping to enable."

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