Cambridge, MA — Robots have been considered too unpredictable and dangerous to work alongside humans in factories. Advances in artificial sensing and motion could change that, according to researchers at the Massachusetts Institute of Technology (MIT).
Last winter, NASA technicians sent a humanoid robot dubbed Robonaut 2 to the International Space Station. R2, which has only a torso, sophisticated arms and fingers, and a head full of sensors, was the result of a joint effort by NASA and General Motors to create a robot that could operate safely alongside humans. (For a full report on R2 application in maintenance work, see the feature ‘I Cobot’ by Bill Roebuck in Machinery & Equipment MRO, Sept. 2010, page 21.)
Robots like R2 could carry out dangerous or tedious tasks on space missions, but they’d also be useful on the ground, where they could assist factory workers. Robots have typically been segregated from humans for safety reasons, but improvements mean they’re now poised to take on a wider variety of tasks.
Although robots have aided manufacturing for decades, they’ve tended to be bulky systems that require precise setup to do large-scale, repetitious tasks such as welding or painting a car door. But improved technologies for vision processing and gripping are leading to a new wave of robots.
In June 2011, the US government announced a US$500 million federal investment in manufacturing technology (including $70 million for robotics), to partners that include Ford, Caterpillar, MIT, Carnegie Mellon University and others. Though the partnership does not include the R2 project, it represents another step in developing robots that can assist with repetitious or physically stressful assembly-line tasks without posing a safety risk.
“In manufacturing facilities, robots are basically in cages like wild animals … so you can’t get in there and get hurt,” says David Bourne, a professor at Carnegie Mellon who works on robotic manufacturing. Having “the robot and person work side-by-side is really scary to a lot of people,” he says. “If it swings around and hits you, it could take your head off.”
R2 uses a popular robotics technology called series elastic actuators in its joints. The actuators have an elastic spring component between the motor and the object the robot has to pick up. The actuators help the robot detect and control the force of its own movements.
“The use of series elastic actuators changes the whole approach to manufacturing robots. [It] makes the robot able to safely interact with people,” says Rodney Brooks, a cofounder of iRobot and founder of Heartland Robotics, which is developing inexpensive, adaptable manufacturing robots and has licensed the series elastic actuator.
In addition to its force-sensing joints, R2 is covered in soft material in case of accidental collisions, and its head is chock-full of cameras-including an infrared camera for depth sensing-so it can keep track of its human colleagues.
“The fact that Robonaut 2 is on the space station is a great example of how safe it is,” adds Brooks. “It’s very promising for assembly operations.”