Researchers from the universities of Groningen (Netherlands) and Stanford (USA) created a robotic pigeon model. Soaring birds do not have a vertical tail keel, but they maintain stability in turbulence without the need for separate wings. The slip caused by the movements of the skaters occurs when the transverse stability of the aircraft is large compared to the rut stability.

While birds lack a vertical stabilizer by constantly changing the shape of their wings and tails, modern pilots maintain stability in roll, pitch (nose up/down) and yaw with rudder and wing ailerons. These are the three rotation angles that determine orientation. normal coordinate system or center of inertia along three axes.

The researchers noted that the pitch could also be stabilized with the help of an aircraft wing sweep or curved airfoils, thus dispensing with the horizontal wing. Another thing is that the feathers are vertical, which gives the “iron bird” stability, controllability and stabilization relative to the vertical axis.

To demonstrate how birds constantly adjust the shape of their wings and tails, scientists developed a robotic model called PigeonBot II. It consists of a biomimetic skeleton and 52 (40 flight and 12 tail) real pigeon feathers. They form wings and a tail that can spread, rise and tilt from side to side. The design includes an algorithm that simulates neuromuscular reflexes that birds are believed to use to stabilize their flight.

The total weight of the model is approximately 300 grams, which is comparable to the weight of pigeons. The design also includes nine servos and two small propellers mounted on each wrist, allowing the robot to ascend, rotate, descend and fly in various poses.

The scientists first spent time in a wind tunnel (without propellers) to tune the installed adaptive reflection controller. This allowed the study to alleviate turbulent disturbances and successfully conduct the experiment outdoors. According to the researchers, their work will help create a more economical and lighter aircraft design without a vertical stabilizer. Additionally, the proposed solution will help reduce the radar visibility of warplanes, making them more effective. The scientific study was published in the journal Science Robotics.