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Robotic Falcon Keeps Birds Away From Airports

Is its large silhouette the real scare factor?

3 min read
A camera view of a flock of birds. Inset photo shows a robotic falcon with a camera on its head.

The inset photo shows RobotFalcon’s view as it hunts corvids.

R.F. Storms/University of Groningen; Inset: M. Papadopoulou/University of Groningen

Collisions with birds are a serious problem for commercial aircraft, costing the industry billions of dollars and killing thousands of animals every year. New research shows that a robotic imitation of a peregrine falcon could be an effective way to keep them out of flight paths.

Worldwide, so-called birdstrikes are estimated to cost the civil aviation industry almost US $1.4 billion annually. Nearby habitats are often deliberately made unattractive to birds, but airports also rely on a variety of deterrents designed to scare them away, such as loud pyrotechnics or speakers that play distress calls from common species.

However, the effectiveness of these approaches tends to decrease over time, as the birds get desensitized by repeated exposure, says Charlotte Hemelrijk, a professor on the faculty of science and engineering at the University of Groningen, in the Netherlands. Live hawks or blinding lasers are also sometimes used to disperse flocks, she says, but this is controversial as it can harm the animals, and keeping and training falcons is not cheap.

“The birds don’t distinguish [RobotFalcon] from a real falcon, it seems.”
—Charlotte Hemelrijk, University of Groningen

In an effort to find a more practical and lasting solution, Hemelrijk and colleagues designed a robotic peregrine falcon that can be used to chase flocks away from airports. The device is the same size and shape as a real hawk, and its fiberglass and carbon-fiber body has been painted to mimic the markings of its real-life counterpart.

Rather than flapping like a bird, the RobotFalcon relies on two small battery-powered propellers on its wings, which allows it to travel at around 30 miles per hour for up to 15 minutes at a time. A human operator controls the machine remotely from a hawk’s-eye perspective via a camera perched above the robot’s head.

To see how effective the RobotFalcon was at scaring away birds, the researchers tested it against a conventional quadcopter drone over three months of field testing, near the Dutch city of Workum. They also compared their results to 15 years of data collected by the Royal Netherlands Air Force that assessed the effectiveness of conventional deterrence methods such as pyrotechnics and distress calls.

Flock-herding Falcon Drone Patrols Airport Flight

In a paper published in the Journal of the Royal Society Interface, the team showed that the RobotFalcon cleared fields of birds faster and more effectively than the drone. It also kept birds away from fields longer than distress calls, the most effective of the conventional approaches.

There was no evidence of birds getting habituated to the RobotFalcon over three months of testing, says Hemelrijk, and the researchers also found that the birds exhibited behavior patterns associated with escaping from predators much more frequently with the robot than with the drone. “The way of reacting to the RobotFalcon is very similar to the real falcon,” says Hemelrijk. “The birds don’t distinguish it from a real falcon, it seems.”

Other attempts to use hawk-imitating robots to disperse birds have had less promising results, though. Morgan Drabik-Hamshare, a research wildlife biologist at the DoA, and her colleagues published a paper in Scientific Reports last year that described how they pitted a robotic peregrine falcon with flapping wings against a quadcopter and a fixed-wing remote-controlled aircraft.

They found the robotic falcon was the least effective of the three at scaring away turkey vultures, with the quadcopter scaring the most birds off and the remote-controlled plane eliciting the quickest response. “Despite the predator silhouette, the vultures did not perceive the predator UAS [unmanned aircraft system] as a threat,” Drabik-Hamshare wrote in an email.

Zihao Wang, an associate lecturer at the University of Sydney, in Australia, who develops UAS for bird deterrence, says the RobotFalcon does seem to be effective at dispersing flocks. But he points out that its wingspan is nearly twice the diagonal length of the quadcopter it was compared with, which means it creates a much larger silhouette when viewed from the birds’ perspective. This means the birds could be reacting more to its size than its shape, and he would like to see the RobotFalcon compared with a similar size drone in the future.

The unique design also means the robot requires an experienced and specially trained operator, Wang adds, which could make it difficult to roll out widely. A potential solution could be to make the system autonomous, he says, but it’s unclear how easy this would be.

Hemelrijk says automating the RobotFalcon is probably not feasible, both due to strict regulations around the use of autonomous drones near airports as well as the sheer technical complexity. Their current operator is a falconer with significant experience in how hawks target their prey, she says, and creating an autonomous system that could recognize and target bird flocks in a similar way would be highly challenging.

But while the need for skilled operators is a limitation, Hemelrijk points out that most airports already have full-time staff dedicated to bird deterrence, who could be trained. And given the apparent lack of habituation and the ability to chase birds in a specific direction—so that they head away from runways—she thinks the robotic falcon could be a useful addition to their arsenal.

The Conversation (3)
Michael Lynch24 Nov, 2022

Since healthy adult large birds like turkey vultures and geese are not generally prey for peregrine falcons, I would not expect them to recognize these drones as predators. Maybe a more appropriate model/drone could be used for these birds?

Viktors Berstis10 Nov, 2022

Sounds like the idea I had some years ago:

1 Reply

Economics Drives Ray-Gun Resurgence

Laser weapons, cheaper by the shot, should work well against drones and cruise missiles

4 min read
In an artist’s rendering, a truck is shown with five sets of wheels—two sets for the cab, the rest for the trailer—and a box on the top of the trailer, from which a red ray is projected on an angle, upward, ending in the silhouette of an airplane, which is being destroyed

Lockheed Martin's laser packs up to 300 kilowatts—enough to fry a drone or a plane.

Lockheed Martin

The technical challenge of missile defense has been compared with that of hitting a bullet with a bullet. Then there is the still tougher economic challenge of using an expensive interceptor to kill a cheaper target—like hitting a lead bullet with a golden one.

Maybe trouble and money could be saved by shooting down such targets with a laser. Once the system was designed, built, and paid for, the cost per shot would be low. Such considerations led planners at the Pentagon to seek a solution from Lockheed Martin, which has just delivered a 300-kilowatt laser to the U.S. Army. The new weapon combines the output of a large bundle of fiber lasers of varying frequencies to form a single beam of white light. This laser has been undergoing tests in the lab, and it should see its first field trials sometime in 2023. General Atomics, a military contractor in San Diego, is also developing a laser of this power for the Army based on what’s known as the distributed-gain design, which has a single aperture.

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