��ƷSM����ӰƬ

Eric Frew is heading a major project to improve drone communications in anticipation of a future when autonomous aircraft regularly whizz overhead for everything from product deliveries to emergency response.

A professor in the Ann and H.J. Smead Department of Aerospace Engineering Sciences at the ��ƷSM����ӰƬ, Frew is the principal investigator of an $8 million, four-year grant to ensure safe and assured operation of commercial autonomous aircraft in populated areas.

“These are complex scenarios -- a drone flying from Denver International Airport to Boulder to drop off a package or using drones to monitor wildfires. Consider the benefit if the Boulder Fire Department could dispatch a drone the moment there’s an incident t so it gets there before police or fire crews,” Frew said.

Communications with consumer-grade quad copters are fairly standardized, but Frew’s team will be studying a much more complex problem – drones that navigate miles from their operator across challenging terrain where line-of-sight communication with a base station is no longer possible.

In such cases, cellular networks are the most likely solution for controlling the drone, but that presents unique challenges.

“Wireless communication is hard,” Frew said. “We’ve all had cell phone signals drop out. That’s fine on the phone with a family member. But if you’re commanding a flying drone, that’s a problem.”

The project team comprises some of the best minds in drones, radio signaling and computer science across 10 universities and colleges; the Center for Autonomous Air Mobility and Sensing research partnership; Boeing subsidiary Aurora Flight Sciences; and the nonprofit Charles Stark Draper Laboratory.

is a partner on the project. An electrical engineering professor at North Carolina State University, he leads a major aerial experimentation laboratory that will offer the team opportunities to develop and test uncrewed aerial system concepts in a real-world outdoor testbed.

“This is advancing the state of the art in an area of critical and timely significance for the United States. We’ll be modeling the behavior of agents, interference, and data in hybrid airborne-terrestrial networks and their impact on the overall performance of the communication network. We will also be supporting real-world experiments and testing needs of project partners at ,” Guvenc said.

Part of the research will focus on designing flight corridors that ensure continued communication. In the case of a trip from DIA to Boulder, that could mean designing a pathway that stays close to cell towers, rather than following the most direct route. Another possibility is using multiple drones as a mesh relay network.

“The transmission would multi-hop back through each drone. We can’t control the ground communications, but we can exploit our own,” Frew said.

Relay networks will be particularly important in sparsely populated areas with fewer cell towers, like during wildfire response in the Rocky Mountains.

“How do we organize stakeholders in that environment? We want to be able to manage team formations, routing and planning so we can work in a hybrid communications system that alternates between air-to-air and air-to-ground communications seamlessly,” Frew said.

Managing that complex interplay will be an area of study for multiple partners on the project, including an assistant professor in computer science at the University of Colorado Colorado Springs. His work focuses on using game theory to inform the design of networked control systems.

“My lab studies the way that network structure impacts team performance for loosely connected teams, which is what a group of drones are in this case. We’re evaluating and predicting the performance of network structures, and also using network structures to inform the decisions made by individual autonomous aircraft,” Brown said.

A key objective of the project is technology transfer to industry. While some grants focus more on early stage research, Frew emphasized their plan to develop software and data to assist business and government going forward.

“This is part of a larger vision of how our work can help society,” Frew said. “The goal is to provide tools to industry to understand and exploit the dynamic communications environment in urban, suburban, rural and remote areas.”