Robots now have much greater dexterity thanks to fingertip sensors

Good as robots are at repeating the same motion over and over, they can’t adapt to situations nearly as well as good ‘old flesh-and-bones. That’s where MIT’s new fingertip sensor comes in. The technology employed to make a robot version of our fingertips is sophisticated, but surprisingly simple. It uses an existing project called GelSight, which is a rubber-like material that can map out a surface in microscopic detail when placed on it. The MIT team used a version that’s 100x less sensitive than the original — but as a result, it’s small enough to fit onto a fingertip, and give real-time feedback about surfaces to the robot.

Researchers at MIT and Northeastern University have equipped a robot with a novel tactile sensor that lets it grasp a USB cable draped freely over a hook and insert it into a USB port. The sensor is an adaptation of a technology called GelSight, which was developed by the lab of Edward Adelson, the John and Dorothy Wilson Professor of Vision Science at MIT, and first described in 2009. The new sensor isn’t as sensitive as the original GelSight sensor, which could resolve details on the micrometer scale. But it’s smaller — small enough to fit on a robot’s gripper — and its processing algorithm is faster, so it can give the robot feedback in real time. Industrial robots are capable of remarkable precision when the objects they’re manipulating are perfectly positioned in advance. But according to Robert Platt, an assistant professor of computer science at Northeastern and the research team’s robotics expert, for a robot taking its bearings as it goes, this type of fine-grained manipulation is unprecedented. “People have been trying to do this for a long time,” Platt says, “and they haven’t succeeded because the sensors they’re using aren’t accurate enough and don’t have enough information to localize the pose of the object that they’re holding.”