In the cusp of building animal-like features (including humans) in robots and other machinery, the scientists have built the artificial flight mechanism for robots, which are naturally present in birds. Even if Pigeons may be considered rats of the sky, some scientists have found greater value in these urban birds while developing a PigeonBot.
Till now the features that used to differentiate between rigid drones and birds – modifying the shape of their wings by fanning out their feathers or shuffling them closer together or adjustments allowing birds to cut through the sky more nimbly – have become narrow. Making the use of new insights into exactly how pigeons’ joints control the spread of their wing feathers, scientists have created a robotic pigeon or PigeonBot, whose feathered wings change shape like the real one.
Researchers at Stanford University invented PigeonBot that has a pair of “biohybrid morphing wings.” The robot is being used to test out new control principles. One of the most interesting aspects of the PigeonBot is that the scientists fitted the flying robot with real bird feathers.
According to David Lentink, a professor of Mechanical Engineering at Stanford University, the motions that bird wings make are seen as far superior to those of an aircraft: “it actually enables birds to fly further, longer, maneuver much better.” He further added, “I really love aircraft as well, but it just doesn’t compare to a bird.”
As per a report, to formulate the robotic design principles for soft feathered morphing wings, the researchers measured the kinematics of feathers as a function of both wrist and finger angle in animated pigeon cadavers using high-resolution motion capture (Materials and Methods). From these measurements, they derived the most parsimonious principles that explain how a bird articulates its flight feathers during wing morphing using the left and right wrist and finger joints as four independently controlled degrees of freedom.
Next, researchers used these design principles to develop a biohybrid morphing wing with 40 underactuated pigeon feathers, which are soft, robust, and light compared with previous robot feathered wings made from carbon and glass fiber. To test the effectiveness of their underactuated soft biohybrid morphing wing, researchers flexed and extended the wing dynamically in a wind tunnel and determined the robotic feather transfer functions under aerodynamic loading. Last, they demonstrated how asymmetric wing planform control via wrist and finger motion initiates turning flight in their new soft biohybrid aerial robot: PigeonBot.
As noted by BGR, the aim of the project wasn’t to just create lifelike bird bots that scientists could send into the skies for fun, but rather to give researchers an easier way to study how the wings of a pigeon work to keep it aloft. That plan has apparently worked splendidly, as a second study using the robotic wings revealed one of the secrets of how pigeon wings move during flight.
The researchers in that study, published in Science, explain that the feathers themselves have “hooks” that latch on to neighboring feathers as the bird flaps its wings. These hooks are so small that you can’t see them with the naked eye, but they were revealed using microscope technology.