A team of engineers at the California Institute of Technology (Caltech) in the US has developed a new control algorithm that programmes a drone to chase birds away from the airspace of an airport to avoid collisions.
The algorithm can reduce economic losses, with the FAA estimating that bird strikes at airports caused $639m of economic loss from 1990 to 2012.
Caltech said that the project was inspired by the 2009 ‘Miracle on the Hudson’ when US Airways Flight 1549 struck a flock of geese shortly after takeoff, which forced the aircraft to land in the Hudson River off Manhattan.
Caltech’s drone herding project principal investigator Soon-Jo Chung said: “The passengers on Flight 1549 were only saved because the pilots were so skilled. It made me think that next time might not have such a happy ending.
“When herding birds away from airspace, you have to be very careful in how you position your drone. If it’s too far away, it won’t move the flock. And if it gets too close, you risk scattering the flock and making it completely uncontrollable. That’s difficult to do with a piloted drone.”
Driving away birds depends on the ability to manage a flock as a single, contained entity, keeping it together while shifting its direction of travel. Each bird in a flock reacts to changes in the behaviour of the birds closest to it.
The drone will position itself in such a way that it encourages birds along the edge of a flock to make course changes that then affect the birds nearest to them.
The positioning has to be accurate. If the external threat gets too aggressive and rushes at the flock, the birds will panic and act individually, not collectively.
To teach the drone to herd autonomously, Chung and his colleagues studied and developed a mathematical model of flocking dynamics to describe how flocks build and maintain formations.
The team trailed the algorithm on a flock of birds near a field in Korea and found that a single drone is able to drive away a flock of dozens of birds out of a designated airspace.