Underground drones could save lives

When disaster strikes, we rely on first-responders to save us. But what if the disaster site is too dangerous for anyone to enter? What happens to the victims?

Engineering faculty won $4.5 million in research funding from the Defense Advanced Research Projects Agency (DARPA) to find a good answer to that question.

Electrical and mechanical engineering experts in the College of Engineering and Applied Science are collaborating with CU Boulder colleagues to build autonomous devices to navigate underground – where lives might be at stake. The group is competing against teams from around the world in DARPA’s three-year Subterranean (SubT) Challenge.

“DARPA is very selective and looks for very ambitious projects to fund, so this level of funding will let us take a big step forward in advancing the state of the art,” said Mark Golkowski, PhD, associate professor of electrical engineering, who’s a member of the project team. “And the collaborative effort has been fun and exciting.”

A flying Roomba on steroids

You might call what Golkowski and his teammates are building a drone, a robot, a flying Roomba on steroids. The team has named it MARBLE – which stands for Multi-agent Autonomy with RADAR-based Localization for Exploration.

MARBLE will consist of multiple autonomous flying and driving platforms designed to move through unknown subterranean environments that may be too hazardous for human first-responders. It could play a key role in military operations or in rescue situations, such as terrorist events, chemical spills, natural disasters, subway accidents and mine explosions.

And since the “A” stands for “Autonomy,” MARBLE will do everything on its own. “All we do is push the ‘Start’ button,” Golkowski said.

MARBLE will learn and map as it goes, finding its way around challenging, unfamiliar underground spaces. Because Wi-Fi and phone signals often don’t work underground, MARBLE will use sound waves at multiple frequencies to send information back to its users above ground.

Not only will MARBLE go where people and other devices can’t, but it will deploy for longer than drones have in the past. Currently, drones have about a 30-minute battery lifetime. The team will develop new power technology to keep MARBLE running for up to three hours.

A perfect fit for collaboration

The idea for MARBLE came about in early 2018 during a road trip to do research in Hugo, Colo. In the car were Golkowski, along with Ron Rorrer, PhD, associate professor of mechanical engineering, Jae-Do Park, PhD, associate professor of electrical engineering, and Vijay Harid, PhD, assistant professor of electrical engineering.

They had recently received a rejection letter in response to the abstract for this same DARPA grant – and they were hungry for another chance.

“At 7 a.m., right before we got in the car, I said, ‘OK, we’re either going to sing show tunes, or we’re going to brainstorm,’” Rorrer said. “By the time we got back to Denver, we had what we thought was a good idea.”

They began meeting on the idea and realized, at a minimum, they needed computer-science expertise, so they asked their colleagues in computer science and mechanical and aerospace engineering at CU Boulder to join the project. Together, they submitted their proposal for a DARPA grant to enter the SubT Challenge, which runs from 2018 to 2021 – and were awarded the grant.

“Between the two campuses, we have enough expertise to cover the whole project,” said Sean Humbert, professor of mechanical engineering at CU Boulder, who’s serving as principal investigator on the project. “It’s a perfect fit, just terrific.”

Theirs is one of just six teams that DARPA selected to receive this funding from hundreds of proposals. CEAS faculty have received DARPA funding in the past, but this is the first time that multiple departments in the university have been involved in a DARPA-funded project.

“This prestigious award shows that we can compete with the best,” Golkowski said.

Exciting research opportunities

Work on MARBLE, which officially began Sept. 1, is already enhancing the student experience in CEAS, Rorrer said.

Currently, four students are involved in the hands-on work, and the hope is for more to contribute going forward, as they develop the specialized skills needed. MARBLE could open the door for students to tackle parallel issues and problems or to develop synergistic senior design projects.

“All DARPA projects are intended to be ahead of the curve on technology, and there are companies following up on those technologies,” Golkowski said. “If you’re involved in this as a student, it could be very helpful in starting an exciting career.”

And Golkowski, Rorrer and their teammates will be equipped to offer new courses from their research, as well.

“With funding of this magnitude, we can take our programs in an even more powerful direction,” Rorrer said.