Flight Control They look real enough to frighten the scarecrows: Climbing hundreds of feet and reaching speeds of 50 miles per hour, remote-controlled falcons and eagles called Robirds flap their wings, swoop and glide so convincingly that other birds scatter. Which is the point. The drones, developed by Dutch inventor Nico Nijenhuis, are meant to rid croplands, airports, dumps and the like of geese, gulls and other pesky birds.
The robotic raptors owe their light weight (1.6 pounds for the falcon, 4.5 for the eagle) to 3-D printed bodies of nylon composite with glass fiber and to a lithium polymer battery. Perhaps the greatest engineering feat was to get lift and propulsion solely from flapping, a complex motion that has long puzzled scientists including, notably, Leonardo da Vinci. Rather than replicating the action exactly, Nijenhuis simplified it. Each foam wing flexes to different degrees across its length and attaches to a double hinge at its base.
In a series of test flights at waste sites in the Netherlands, prototype Robirds reduced pest bird populations by up to 75 percent over time. Tests at airports—birds collided with aircraft in the United States some 11,300 times in 2013 alone—are set for spring of next year. One day Robirds might be equipped with autopilot and radar to track avian targets, but for now Nijenhuis says he’s keeping things basic: “It can be tempting to put too much technology into the bird.”