Screenshot of the eagle-inspired flapping-wing drone Photo: CCTV Military Program

Four flapping-wing drones developed by a research team at the University of Science and Technology Beijing (USTB), which feature eagle, pigeon, butterfly and beetle imitations, have recently gained widespread public attention. Among them, the eagle-inspired flapping-wing drone achieved a single continuous flight time of 256 minutes, media reported on Thursday.

The flapping-wing drone is a type of bionic unmanned aerial vehicle that mimics the flight of living creatures by flapping and vibrating its wings to generate lift, rather than relying on high-speed propellers or engines. This type of drone is currently the aircraft that most closely resembles flying organisms in nature. The eagle-inspired flapping-wing drone, by imitating the unique visual structure of eagles, can accurately identify and track ground targets at various distances. 

According to a report from the CCTV Military Program, the team's eagle-inspired flapping-wing drone set a record with a single continuous flight time of 256 minutes.

In 2023, a bionic aircraft, developed by researchers at China's Northwestern Polytechnical University, broke the Guinness World Record for flight time of a flapping-wing drone, with a record of 185 minutes and 30 seconds, CCTV reported.

"We developed a visual system combining telephoto and short-focus lenses by imitating the special visual structure of eagles. This system enables precise recognition of targets at different focal lengths and distances, such as vehicles, license plates, people and buildings. Once detection is complete, we can locate these targets. After obtaining positioning information, we can quickly track both static and dynamic targets," explained Wu Xiaoyang, a lecturer at the School of Intelligence Science and Technology of USTB, according to the report by the CCTV Military Program.

In reality, the wings of birds in flight are flexible. This flexibility is crucial for generating high lift in flapping-wing drones. In addition to flexibility, structural design, modeling and control also have a vital impact on their flight capabilities, the report said citing a relevant researcher. 

Future research directions aim to make these bionic drones smarter and more autonomous, the researcher said.

From the perspective of domestic technological development, there are still several key challenges to overcome in order to perfect flapping-wing drones: high-energy-density batteries, high-precision and miniaturized flapping mechanisms; and adaptive deformation in wing materials, Wang Zhijie, an expert in flapping-wing drones from the School of Mechatronics Engineering of Beijing Institute of Technology, told the Global Times on Thursday.

"When birds fly, their wings automatically change shape in response to aerodynamics. This flexible deformation is key to achieving efficient flight. Therefore, figuring out how to make wing materials adapt and deform like those in nature remains a significant technical hurdle," Wang noted.

The advancement of such bionic technology not only demonstrates China's strong scientific research capabilities in the field of unmanned aerial vehicles, but also opens up more possibilities for future applications in environmental monitoring, disaster rescue and specialized mission detection, the expert said.