Robot with human reflexes
Researchers from MIT’s Department of Mechanical Engineering have designed an interface that takes advantage of a human’s split-second reflexes allowing a humanoid to maintain its balance and complete tasks.
Deep in the basement of MIT’s Building 3, a two-legged robot named HERMES is wreaking controlled havoc: punching through drywall, smashing soda cans, kicking over trash buckets, and karate-chopping boards in half. Its actions, however, are not its own.
Just a few feet away, PhD student Joao Ramos stands on a platform, wearing an exoskeleton of wires and motors. Ramos’ every move is translated instantly to HERMES, much like a puppeteer controlling his marionette. As Ramos mimes punching through a wall, the robot does the same. When the robot’s fist hits the wall, Ramos feels a jolt at his waist. By reflex, he leans back against the jolt, causing the robot to rock back, effectively balancing the robot against the force of its punch.
The exercises are meant to demonstrate the robot’s unique balance-feedback interface. Without this interface, while the robot may successfully punch through a wall, it would also fall headlong into that wall. The interface allows a human to remotely feel the robot’s shifting weight, and quickly adjust the robot’s balance by shifting his own weight. As a result, the robot can carry out momentum-driven tasks — like punching through walls, or swinging a bat — while maintaining its balance.
Ramos says the interface takes advantage of a human’s split-second reflexes, which give the robot much faster reaction times than robots that adjust their balance based on visual feedback from onboard cameras.
“The processing of images is typically very slow, so a robot has difficulty reacting in time,” says Ramos, of MIT’s Department of Mechanical Engineering. “Instead, we’d like to use the human’s natural reflexes and coordination. An example is walking, which is just a process of falling and catching yourself. That’s something that feels effortless to us, but it’s challenging to program into a robot to do it both dynamically and efficiently. We want to explore how humans can take over complex actions for the robot.”
Ultimately, Ramos and his colleagues envision deploying HERMES to a disaster site, where the robot would explore the area, guided by a human operator from a remote location.
“We’d eventually have someone wearing a full-body suit and goggles, so he can feel and see everything the robot does, and vice versa,” Ramos says. “We plan to have the robot walk as a quadruped, then stand up on two feet to do difficult manipulation tasks such as open a door or clear an obstacle.”