Air Force-Funded Research Team Demonstrates Increased UAV Capabilities

  • Published
  • By Erin Crawley (Quantech)
  • AFOSR Public Affairs
ARLINGTON, Va --  A Brigham Young University team of scientists and engineers, funded by the Air Force Office of Scientific Research here, has recently demonstrated increased consensus capabilities among unmanned air vehicles.

"This research on cooperative control involves developing methods to enable multiple UAVs to coordinate with one another," said Professor Tim McLain, one of the research team co-leads. "We want to figure out how to coordinate the activities of a team of UAVs to accomplish the overall objectives of the team in a way that is optimal for the team as a whole." Also leading the team is Professor Randy Beard.

On the road to accomplishing their research goals the team has had many successes.

"We've developed and demonstrated cooperative timing methods that would enable simultaneous strike-type execution by UAVs," said McLain.

In one experiment the team conducted simultaneous arrival flight tests involving three UAVs. The team was able to coordinate the UAVs' arrival over a target location to within fractions of a second. Another flight test demonstrated a successful UAV coordination, even in the presence of inconsistent information. The researchers conducted a successful perimeter tracking exercise where the changing perimeter emulated the growth of a forest fire. The exercise involved a team of UAVs coordinating their efforts to divide the changing perimeter equally among the UAVs. This technology has application to Air Force missions such as monitoring the perimeter of an enemy stronghold.

One of the team's most exciting research developments is in an area that McLain refers to as 'corridor-following methods.' Utilizing miniature optic-flow sensors, these methods allow small UAVs to navigate through complex terrains like canyons and city environments.

"Maneuvering small UAVs in urban terrain will require local proximity sensors to detect the buildings and other obstacles. The optical flow sensor that we have developed under AFOSR support play the same role for small UAVs that ultrasonic sensors play for mobile robots," said Beard.

The simulation and experimental work conducted by the team serves as a complimentary approach to achieving results.

"We've done some simulation and that's an important part of the work. But, our strength is flight tests and flying the experiments that we develop. We've had a lot of success with that," said McLain. Most often the experimental research takes place in areas near the BYU campus, making it convenient for the research team to perform their flight tests.

"We are fortunate that our campus is near some fairly remote areas. We basically fly over farm pastures within current FAA regulations for small autonomous air vehicles. Our airplanes are designed to be hand launched and land on grass, so we don't have to travel long distances to a dedicated airstrip or a base," said McLain. According to McLain the team has had most of its success in testing UAVs with a 3-to-5-foot wing span that are made of foam with a Kevlar shell. They are tough and durable and can take the abuse that experimental flight testing involves, said McLain. "The experimental platform uses the Kestrel autopilot which was originally developed at BYU leveraging Defense Advanced Research Projects Agency and AFOSR support. The Kestrel autopilot is currently used in the Air Force Research Laboratory BATCAM micro air vehicle,'' said Beard.

Lt. Col. Sharon Heise, an AFOSR program manager, oversees AFOSR's dynamics and control grant portfolio, which includes the research grant to McLain and Beard. Heise believes their work is critical to the Air Force mission.

"Tim and Randy's theoretical work in consensus seeking for multiple unmanned vehicles, combined with their research team's capability for rapid prototyping and experimentation, provides a powerful path forward to rapidly mature basic research and opportunistically insert it into the emerging Air Force systems," said Heise.

McLain said the AFOSR funding they've received has played a major role in their success. "I think the key thing about the AFOSR funding is that it enables us to attract the very best students and put them to work on exciting problems. We mentor them, guide them and, as a result, we get great outcomes. With the best students you can do great things," said McLain.

In addition to having potential benefits to a variety of military applications, McLain and Beard said their research will contribute to civil and commercial applications such as forest fire monitoring, law enforcement surveillance, and border patrol.

By funding research efforts that investigate technological challenges such as cooperation and consensus for teams of UAVs, AFOSR continues to expand the horizon of scientific knowledge through its leadership and management of the Air Force's basic research program. As a vital component of AFRL, AFOSR supports the Air Force's mission of control and maximum utilization of air and space. Many of the technological breakthroughs enjoyed by millions today, such as lasers, the Global Positioning System, and the computer mouse trace their scientific roots to research first funded by AFOSR."