By Edwin L. Aguirre
Robots are designed to work in extreme environments like the surface of Mars and to assist in situations deemed too hazardous for humans, such as disaster-relief missions, bomb-disposal operations or nuclear waste cleanup.
Thanks to a three-year, $1.5 million grant from the U.S. Department of Energy (DOE), a team of robotics experts from UMass Lowell and Northeastern University is studying ways in which a humanoid robot can help clean up the remaining traces of plutonium — a highly toxic and radioactive chemical element — from America’s deactivated and decommissioned nuclear production facilities.
NASA’s Valkyrie robot, currently residing at UMass Lowell’s New England Robotics Validation and Experimentation (NERVE) Center, will be used in the research. “We are going to use Valkyrie to investigate how we could replace a human working in a dangerous, high-radiation environment with a remotely operated humanoid robot, so the human will be kept out of harm’s way,” says computer science Prof. Holly Yanco.
An expert in robotics, assistive technology and artificial intelligence, Yanco directs the NERVE Center and is collaborating with Prof. Taskin Padir of Northeastern on the DOE project.
The project’s goal is to demonstrate the feasibility of using Valkyrie to decontaminate and maintain the gloveboxes used in the Plutonium Fuel Form Facility at the Savannah River Site in South Carolina. A glovebox is an enclosure that enables people to safely handle and process hazardous materials through rubber gloves mounted on the box. There are more than 3,500 gloveboxes in use at the Savannah River Site.
The Plutonium Fuel Form Facility was originally designed and operated to manufacture plutonium pellets for NASA from the late 1970s to the early 1980s. The space agency used the pellets in the thermoelectric generators that powered its long-mission deep-space probes, such as Galileo and Ulysses. The DOE is interested in training Valkyrie to automate routine tasks like the day-to-day cleaning and maintenance of the facility’s gloveboxes.
“The airborne nature of the plutonium isotope Pu-238, still present in the gloveboxes, makes the decontamination process extremely dangerous for humans to perform,” says Yanco.
Giving Valkyrie 'X-ray' Vision
“Valkyrie is a perfect candidate for the job, since it is shaped like a human and has the dexterity to operate tools and perform a wide variety of tasks,” explains Yanco. “We just need to modify the gloveboxes slightly to accommodate her bulky upper arms, or the robot could be redesigned for future use.”
Yanco and her collaborators will fit additional touch and pressure sensors on Valkyrie’s palm and the pinky-finger slot of her gloves (the robot has only four fingers). Combined with Valkyrie’s stereo cameras, the sensors will give the human remote operator — wearing a virtual reality headset called Oculus Rift — an immersive, 3-D view of the inside of the glovebox.
“The operator would feel as if he or she is there, touching and feeling objects through the gloves,” says Yanco. “The operator can be located in a separate room or outside the building.”
Obviously, the operator would not be able to see objects hidden beneath Valkyrie’s gloved hands, so the team will install sensors that would be able to see through the gloves, like in “X-ray” vision, and provide an augmented-reality view of the workspace.
“We will create a 3-D representation of what’s inside the workspace,” she says. “The operator can still see the faint outline of the robot’s hands, but now he or she can also see what Valkyrie is holding or manipulating.”
Yanco says the project can lead to safer work environments.
“There has been a lot of concern about robots taking over people’s jobs,” says Yanco. “I don’t see it that way. The person is still going to do the job; he or she is just doing it from a safe location. The robot isn’t smart enough or capable enough to do everything on its own, but it is a better stand-in for a person, especially in a ‘hot zone’ where there’s a lot of radiation involved. Since robots need assistance, there’s still a need for people to do the work.”