Unmanned aerial vehicles (UAVs) — commonly called drones — are predominantly in use in military operations. But engineers are discovering a wide range of civilian applications for these versatile vehicles — from farming and wildfire fighting to search-and-rescue operations, building inspections, and environmental monitoring.
As Oregon positions itself to be a national leader in the research, development, and manufacturing of the fledgling UAV sector, Oregon State University’s College of Engineering is growing its faculty expertise in this area, responding to burgeoning student interest, and offering the first UAV engineering course in the Pacific Northwest this fall.
Roberto Albertani, associate professor in the School of Mechanical, Industrial, and Manufacturing Engineering, joined Oregon State in 2010 after working in industry for 23 years. He helped design and manufacture high-tech composite materials used in wind turbine blades, high-speed trains, yachts, helicopters, and Ferrari and Lamborghini cars. He also served as the science advisor for the Italian sailing team in two America’s Cup races and the 1996 Olympic Games in Atlanta, Georgia.
Since earning his Ph.D. at the University of Florida in 2005, Albertani has been studying the flight mechanics of bats and butterflies, incorporating some of the elasticity found in mammal and insect wings into the wings of micro UAVs.
“My work is about using bio-inspiration to enhance the efficiency and increase the maneuverability of UAVs,” he said. “The main limitations to maneuverability in any manned aircraft are the biological limits of human pilots, such as exposure to extremely high inertial loads or very long endurance flights. An autonomous aircraft avoids these limitations.”
In collaboration with researchers at Harvard University, Albertani has been looking for ways that UAVs can recover and continue flying after colliding with an obstacle.
“A butterfly or dragonfly can crash into plants or trees, but they keep flying,” he said. “This is a very a complicated engineering problem for artificial flight, because you need to devise special wings or propellers that will not be affected by impact.”
Albertani directs the Applied Mechanics and Composites Lab at Oregon State, where he develops micro UAV prototypes featuring thin, pliable, skin-like membranes incorporated into sections of the wings. This added elasticity makes the wings less susceptible to impact damage, enables greater maneuverability, and produces more stable flights — an advantage when using on-board micro cameras.
“The energy of wind gusts, for example, is absorbed by the membrane so there is less disturbance to the aircraft’s flight,” he said.
At the University of Florida, Albertani developed two UAVs with foldaway wings for U.S. military applications. One was small enough to be carried inside a pocket and deployed by hand. The other one was larger and designed to be dropped from an aircraft at 40,000 feet and free-fall until a certain elevation, when the wings would unfold and the UAV would take flight.
Albertani is currently working with an Oregon startup to develop an airborne wind energy turbine, which is essentially a wind-propelled UAV that is tethered kite-like to the earth. It generates electricity by flying particular patterns, spooling and unspooling the tether.
“For this application, the desirable structure must be elastic, pliant, and able to change shape in flight in order to increase efficiency,” he said.
Albertani teaches aerospace engineering and composite materials courses. Next fall, he will offer UAV Engineering, an upper level undergraduate course. He is also the faculty advisor (along with Nancy Squires) for Oregon State’s student chapter of the American Institute of Aeronautics and Astronautics.
Each year, the student club designs a UAV and competes against other teams at a national competition. Last year, the Oregon State team placed 14th out of 81 for overall score and won 6th place for flight performance. In August 2012, the club had less than a dozen members. Last year, membership had grown to more than 100.
“Interest has just ballooned,” Albertani said. “It’s quite amazing that we have so many students, given that we don’t have an aeronautics program.”
He credits the uptick in UAV interest to Oregon’s growing number of UAV-related companies. Also, the Federal Aviation Administration recently approved three locations in Oregon as UAV test sites — part of a collaboration led by the University of Alaska and involving Oregon State and the University of Hawaii.
“We have such a diversity in skills at this university, and our location — close to the coast, the mountains, and the desert — is ideal for UAV development,” said Albertani.
In addition to Albertani, other faculty in the College of Engineering are engaged in research related to UAVs.
Dan Gillins, assistant professor of geomatics in the School of Construction and Civil Engineering, is gearing up to make UAVs a major focus of his research.
“We recently acquired a UAV, and I plan to explore the advantages and disadvantages of using small, inexpensive UAVs to survey land, perform structural inspections, and film damage following extreme events like earthquakes, floods, and landslides,” said Gillins. He will compare images captured by UAVs to images captured using traditional photogrammetry techniques, which rely on much more expensive, higher altitude, manned flights.
Christopher Parrish will join Gillins this fall in the School of Civil and Construction Engineering. He currently serves as lead physical scientist in the Remote Sensing Division of the NOAA’s National Geodetic Survey and is an affiliate professor of ocean engineering and earth sciences at the University of New Hampshire. Parrish is currently involved in proof-of-concept studies with the NOAA and university colleagues, investigating the use of small UAVs for coastal wetlands mapping.
“I’m definitely planning on extending this work at OSU and I hope to incorporate UAVs in a grad-level course on kinematic surveying and navigation that I’ll be teaching next year,’ said Parrish. “I’m also interested in the potential use of small, fixed-wing UAVs for coastal mapping in remote areas and for emergency response.”
Geoffrey Hollinger, an assistant professor in the School of Mechanical, Industrial, and Manufacturing Engineering, directs the Robotic Decision Making Laboratory at Oregon State, where he and his students design techniques for planning, coordination, and learning to improve robotic sensing in the physical world. Application domains include unmanned aerial systems (precision agriculture and forestry, for example) and marine systems (ecological monitoring, climate change investigation, and facility inspection, for example).
Albertani believes that UAVs will be used increasingly in the future to save both time and lives. Applications include inspecting high voltage transmission lines, monitoring the impact of wind turbines on bird populations, and designing safer approaches to wildfire fighting.
“I don’t comprehend why UAVs have not been used years ago in wildfire fighting,” he said. “That tragedy in Colorado probably could have been avoided had there been a UAV overhead transmitting data that would have predicted the trajectory and timing of the fire.”
— Gregg Kleiner