SPECIA L SECTION
RO B OT S
Meet your new co-worker At the vanguard of human-robot interactions is Baxter, a bot quick on the uptake that even knows how to cheat By John Bohannon, in Boston
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except for one dropped nipple—efficiently transferring them from box to conveyor belt. As I will soon hear from Rodney Brooks, the legendary roboticist who founded the company, getting a robot even to this level of success on tasks like these normally takes an engineer weeks or even months of work. I did it in 5 minutes without an engineering degree. If I can teach Baxter, surely the average factory manager can, too. But would the average factory employee be comfortable with a robot co-worker?
people is at least as much about human psychology as it is about robot engineering. Just the appearance of a robot can be a barrier—especially if it falls within the uncanny valley, a term introduced by Japanese roboticist Masahiro Mori in 1970. A zone of discomfort lies somewhere between robots that are obviously nonhuman—something cute like the late 1990s toy Furby—and robots like the replicants from the 1982 film Blade Runner, so humanlike that you can’t perceive the difference. Robots that look almost-but-not-quite human creep us out, and no one knows why. According to one theory, they are similar to corpses. A machine’s movements are another barrier. The challenge is to create robots that are less robotic, says Guy Hoffman, a roboticist at the Interdisciplinary Center Herzliya in Israel. Just like the “user interface” that enabled the personal computer revolution, a movement-based “robot user interface” is needed, he says. In some circumscribed domains, progress has been impressive. For
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PHOTOS: (LEFT TO RIGHT) BENJAMIN ECKSTEIN; RETHINK ROBOTICS
MAKING A ROBOT that collaborates with
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“W
e are pleased to confirm periments in human-robot interaction were receipt of your order for limited to custom-built bots that required fifteen thousand robots,” careful supervision to avoid harming husays the industrialist Harry man or robot. Baxter was built to interact Domin in the opening scene safely with humans. “I can even let my high of R.U.R., a 1920 play writschool interns work with it unsupervised,” ten by Karel Čapek. Čapek coined the word Scassellati says. And crucially, Baxter, by de“robot” from robota, which in Czech means sign, learns from people. forced labor or drudgery. He imagined a future in which the global economy runs on WHEN I ASK CHRIS HARBERT if I can humanoid automatons. Things get stirred play with one of the $25,000 humanoids in up when an activist named Helena appears the Rethink Robotics offices here, he doesn’t at Domin’s company, demanding equal flinch. “Go for it,” he says, taking a step back rights for robots. He dismisses her concerns. from Baxter. The big cartoon eyes on the roOnce in a while a robot working on an asbot’s face—a computer screen mounted on sembly line goes crazy, “smashing up all a swivel neck—stare down at an unmoving the moulds and models,” admits one of the conveyor belt cluttered with objects. Its hulkcompany’s human employees, but Domin ing red arms hang open in a shrug, as if to assures Helena that the robots are soulless say, “I’m ready for whatever.” and have no desire for rights or freedoms. Nearby is a box of white plastic widgets Nearly a century later, at least some of that look like giant nipples. The goal, I deČapek’s vision is starting to come true. Macide, is for Baxter to pick them up and place chines are now capable them on the conveyor of carrying out certain belt. Baxter learns by tasks on an assembly example, so I grab one line—such as welding of the robot’s arms and car frames or spraypull it into position painting parts—far over one of the widgets. more efficiently than The plastic-cased steel humans. And they are limb is as thick as a now developing some human leg, but moving of the dexterity and it requires surprisingly awareness needed to little strength. The roserve as pets and helpbot is paying attention: ers in homes, as careIts head turns, and its givers in hospitals, and cartoon eyes track my as co-workers in factohand. I lower Baxter’s ries (see p. 188). But for hand into position and people to truly embrace press a button on the bots in their daily lives, Baxter has a variety of “hands” adapted to arm, making it seize the the machines will need specific tasks. widget with its pincer social smarts. “These grabber, which is remiare exciting times for human-robot interniscent of the robot from the 1960s TV show action,” says Brian Scassellati, a roboticist at Lost in Space. Yale University. With a gentle tug, I guide the arm to the Like many others in his field, Scassellati far side of the conveyor belt, lower the hand, has adopted a robot, called Baxter by its press the button again, and Baxter drops the manufacturer, as his research subject. The widget. Scaling up this task takes me a few company behind Baxter, Rethink Robotics, more steps, with minimal guidance from is selling it to manufacturing companies. Harbert. Holding Baxter’s hand, I trace an The hope is that assembly lines are poised imaginary square over the widgets and then for disruption by a versatile robot that can over the destination, defining the pickup take over repetitive, mind-numbing tasks. and drop-off areas. And then, with an actual In the meantime, Baxter is serving as a test nod of its computer-screen head, Baxter gets subject for robot psychology. In the past, exto work, mimicking my movements and—
Humans can infer Baxter’s intentions from “emotions” expressed on the bot’s flat panel display “face.”
example, Hoffman created the world’s first robot that can play improvisational jazz in an ensemble with humans. But to live and work side by side with humans, he says, a robot must understand your intentions and act appropriately, “looking you in the eyes, touching your shoulder, coming closer or shying away.” Baxter has none of those social graces. But the scientists using the robot in their labs are trying to create a road map to get there. Scassellati is working with a simple system. Baxter has only six facial expressions, ranging from sleepy and content to confused and surprised, each of which signals a different internal state. “The important thing is that you should be able to work with Baxter with as little special training as possible,” says Miri Bauman, the designer of Baxter’s user interface. One ongoing experiment has generated surprising results. “We’ve been having Baxter play checkers with humans,” Scassellati says. At a certain point in the game, Baxter cheats. The social dynamics change abruptly. “People interact with the robot like a person,” he says. Without realizing that they’re doing it, the subjects start talking to the robot, making eye contact, and maintaining human-appropriate social distance. “It’s a powerful effect,” he says. “If you want people to treat a robot like a person, have the robot cheat.” Roboticists hope that more sociable tricks like joking and sarcasm will achieve the same effect. With some human subjects, no subterfuge is necessary to elicit profound effects. For example, Scassellati has been working
with a 12-year-old boy with autism spectrum disorder. “He is high-function, but if you met him on the street, you’d immediately recognize him as autistic,” he says. The boy avoids eye contact, has difficulty communicating, and makes repetitive movements. “But we put him in a room with the robot and he changes.” The boy gazes right into Baxter’s eyes, using his gaze to signal what he’s thinking. “We take the robot away and the effect lasts maybe 15 minutes and it’s gone,” Scassellati says. “We don’t understand what’s going on, but dozens of labs have replicated this effect.” Scassellati is also using Baxter to study the other side of the equation: getting robots to read our minds. In one experiment, Baxter works with people at a tabletop to assemble Ikea furniture. The robot knows the blueprint, but it also must anticipate what the human will do next. Fellow humans find it effortless to guess why you’re looking for all the pieces of a particular shape, but that represents a steep challenge for Baxter. It requires what psychologists call the theory of mind, which has yet to be captured in computer code. “This is the frontier of human-robot interaction,” Scassellati says. At this point, humans are better off muddling through Ikea furniture assembly on their own. “I TAUGHT BAXTER a task,” I tell Brooks.
“He’s impressive.” “It’s an it. Or if anything, a she,” Brooks says in his broad Australian accent. The original meaning of the word “baxter” is a female baker, he explains. “But everyone makes
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this mistake.” The misattribution isn’t bad news—it indicates that Baxter’s “robot user interface” is working—but Brooks worries that “robots shouldn’t make promises they can’t keep.” Baxter isn’t designed to have much of a personality, let alone a gender. There is one promise that Baxter is programmed to keep, at all costs: It will do its utmost not to hurt you. (Unlike Čapek’s robots, which rise up and exterminate humanity.) “Robots are extremely dangerous,” explains Brooks, whose lab at the Massachusetts Institute of Technology in nearby Cambridge has churned out a large proportion of today’s leading roboticists, including Scassellati. The industrial robots on assembly lines today simply aren’t safe to be around. “The robots work in their own room, people work in another, and the two don’t mix,” he says. “Baxter is meant to bridge that gap.” Brooks’s team has built several layers of safety into Baxter. It constantly searches for the presence of humans with a 360° sonar system, halting if anything gets too close. If a human insists on getting in the way of the arms, Baxter’s plastic armor and control system—the key is a special spring called a series elastic actuator—soften the blow. “When I’m giving demonstrations I like to stick my head in the way to show that it doesn’t hurt,” Brooks says. He knows that if Baxter were to cause a single serious injury, its days would be numbered. And what about harming livelihoods? “It’s not about taking people’s jobs,” Brooks says before I even ask the question. Rather than replacing workers, he says, Baxter will free people to do higher level tasks. “Robots have a long way to go before they can completely replace someone working in a factory.” For a start, he says, robots lack “dexterous manipulation.” To demonstrate, Brooks stands up and pulls his keys out of his pocket. “What I just did is nearly impossible for a robot,” he says. Another impediment is robot vision (see p. 186). “And then there’s the problem of mobility,” Brooks says. “Stairs are a nightmare for robots.” After chatting with Brooks, I walk down the hall to see how Baxter is doing. At the end of my robot tutorial, I’d asked Harbert to instruct Baxter to do something that would drive a human insane: After placing the widgets on the conveyor belt, put them back in the box, and repeat that in an infinite loop. I find Baxter toiling away, unsupervised, delicately moving widgets onto the belt, one at a time, and then putting them back. Like Sisyphus, but without the suffering. ■ 10 OCTOBER 2014 • VOL 346 ISSUE 6206
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