Engineers at the California Institute of Technology have developed an algorithm that uses a single drone to redirect a flock of birds away from an airport. Associate Professor and Jet Propulsion Laboratory Research Scientist, Soon-Jo Chung, created the algorithm with his colleagues in response to the “Miracle on the Hudson” incident. In 2009, US Airways Flight 1549 was forced to ditch in the Hudson River after flying into a flock of Canada Geese shortly after takeoff from New York’s LaGuardia Airport.
"The passengers on Flight 1549 were only saved because the pilots were so skilled," Chung said in a CalTech news release. "It made me think that next time might not have such a happy ending. So I started looking into ways to protect airspace from birds by leveraging my research areas in autonomy and robotics."
Current strategies for scaring birds away from airports include using trained falcons, dogs or piloting drones which, according to Chung, are not viable methods. Originally based on algorithms for herding sheep, the one developed by Chung and his colleagues focuses on moving a flock of birds as a single entity. Their algorithm was presented in a study in IEEE Transactions on Robotics.
The algorithm positions a single drone near a specific part of a flock in order to force the birds at the edge to start making course changes that affect the birds that are closest to them, with the pattern continuing deeper into the flock, eventually changing the direction of the entire group. The positioning of the drone is key because a threat that moves at the birds too quickly can cause them to panic and scatter.
"We carefully studied flock dynamics and interaction between flocks and pursuers to develop a mathematically sound herding algorithm that ensures safe relocation of flocks using autonomous drones," says Kyunam Kim, postdoctoral scholar at Caltech and a co-author of the IEEE paper.
The algorithm was tested by Chung and his colleagues in Korea where it was discovered that one drone could keep a flock of dozens of birds away from specific airspace. The effectiveness of the algorithm is only affected by the number and size of birds. Chung and his team are currently planning to develop the project further in order to have multiple drones control multiple flocks.