How To Build A Hero

DRC-HUBO: Drexel University: The competition’s manipulation-related tasks, which could include attaching a fire hose and closing a valve, will be difficult for bots with only three digits. Drexel’s HUBO prototype, which will be further developed by a 10-school coalition, has dexterous five-fingered hands. It has already demonstrated the ability to grip a wide range of objects—from balls and bottles to power tools.  Graham Murdoch

On the same testing field that CHARLI-2 just crossed, the precursor to both THOR and SAFFiR takes its first steps of the day. There’s real menace in this thing: Its actuators whine with each movement, and the blue indicator lights at the apex of its truncated torso are just the right amount of ominous. It walks while tethered to a wheeled carbon-fiber and aluminum gantry (to catch it should it fall) with an amber warning light and bright-red emergency-stop buttons. The arms, which are still being built, will have roughly the same strength as an adult man. But the legs are superhuman. According to the team members from RoMeLa, the legs unexpectedly sheared through aluminum alloy that they placed as a buffer between the heels and ankles. This robot is already more powerful than the team predicted, able to whip its legs forward faster than the eye can track.

But its movement isn’t exactly the stuff of sci-fi nightmares. For all its power and musculature, the prototype is slow. Of course, this is only its third day of walking, and the algorithm it’s using is borrowed from CHARLI-2. So while its footstep is longer and its actuators are faster, I’m seeing only a fraction of its eventual speed. RoMeLa hopes to prove that bipedal robots can use energy more economically too; if the linear series elastic actuators perform as expected, they could cut into the efficiency gap between the living and the robotic. A humanoid that burns only five times more energy while walking than a human would be a significant engineering breakthrough.

Power is always a cause for concern in robotics, but it’s particularly problematic during today’s test walks. One of the advantages of this humanoid’s design is that the actuators can recover a small amount of energy during each step, similar to regenerative braking
in a hybrid-electric vehicle. But the right knee is acting up. It’s recovering too much energy, so the electricity spikes and triggers an automatic shutdown, which causes the robot to tip over. That’s the hypothesis, at least. Later, as the robot stands still, actively balancing itself, Hong boosts himself onto the machine. Its 66-pound frame takes his entire body weight without buckling or suffering a crippling power spike. The knee can’t be stressed into failing. Its power surges seem to be happening at random.

First, they’ll save lives. Later, they can save the weekend from chores.The RoMeLa team records the data and moves on. There are months, maybe years of troubleshooting ahead. Some of the solutions will be specific to the tasks at hand. But others will apply to the larger enterprise of bots that function in a human world. “The greatest example of a high-risk, high-payoff project is a humanoid,” Hong says. “If it can fight a fire, then you can use it for mopping the deck, cooking the food, delivering stuff to you. That’s why I call it the Swiss Army knife of robots. If you succeed, you can use it for most everything.”

That’s the long-term promise of THOR, SAFFiR, and other humanoid prototypes: that they will lead to initial generations of restricted, million-dollar systems, and as complex components get field-tested and mass-production kicks in, everything will become cheaper. Robots for military and medical missions will have paved the way for consumer models, the ones that assist the aged and disabled, weed gardens, and do laundry. First, they’ll save lives. Later, they can save the weekend from chores.

The initial public test of RoMeLa’s engineering will occur this November, when SAFFiR is scheduled to step aboard the U.S.S. Shadwell, a decommissioned World War II–era ship currently docked in Mobile, Alabama. It probably won’t spray any hoses or lob any canisters, but rather walk around and get its proverbial sea legs. A month later, THOR will compete in the first of its tasks. Other trials will follow, including a Navy pallet fire and DRC’s simulated disaster, both slated for 2014.

Whatever the results of the DARPA Robotics Challenge—even if it points toward a hybrid robot made up of the best-performing limbs, postures, and control schemes—the real question isn’t whether robots will ever be ready for active, meaningful deployment. Just as DARPA’s Grand and Urban Challenges accelerated the development of robotic cars and ultimately led to Google’s self-driving Priuses, the Robotics Challenge will drive progress toward a truly capable robot. After the competition, it will be only a matter of when they enter society and how.

It could take a decade or two for the robots to appear in hospitals, helping patients in and out of beds, or at construction sites in the coldest winter months, working the all-robot graveyard shift. But before then, you could see humanlike machines march into a disaster. Perhaps they’ll show up online, glimpsed in shaky cameraphone footage. Or maybe you’ll see one in person, looming forward through the smoke, its hand reaching for yours.

Erik Sofge wrote about future space-suit technology for the November 2012 issue of Popular Science. This article appeared in the February issue of the magazine.