Flying organisms such as insects and birds are thought to be able to fly well on the ground by generating aerodynamic forces that support their own weight mainly by forming leading edge vortices on the wing surfaces.However, at high altitudes, where the air density is less than on the ground, the aerodynamic forces generated by the wings are likely to be reduced due to flow separation and vortex shedding.Although bumblebees and monarch butterflies have been confirmed to fly at high altitudes, the mechanism by which organisms fly in environments where lift force is reduced remains unclear.Also, due to the difficulty of conducting experiments in low atmospheric density environments, the development of flapping wing-type flying robots at high altitudes has not been realized.
Against this background, a joint research group consisting of Shinshu University, Tohoku University, Kyushu University, Maebashi Institute of Technology, and the University of Alabama has developed a flapping wing-shaped flying robot modeled after a hummingbird (Robo Hummingbird Shinshu). was placed in a low-density environment constructed in the decompression chamber of the Mars Atmospheric Wind Tunnel owned by Institute of Fluid Science, Tohoku University, and an experiment was conducted to measure wing movement and aerodynamic force.
An analysis of the experimental data revealed that by skillfully adjusting the wing size and flapping frequency, even at high altitudes, a large amount of lift can be obtained by the same aerodynamic mechanism as the biological flapping flight mechanism on the ground.As a result, we successfully lifted off the world's first flapping wing-shaped flying robot at an altitude of 9000 m with a low atmospheric density (approximately one-third that of the ground).
This result indicates the feasibility of flight in a low-density, high-altitude environment by utilizing the aerodynamic mechanism peculiar to flapping wings.It is expected to lead to the elucidation of the high-altitude flight mechanism of organisms, and it may lead to the realization of flight of flapping wing-type flying robots in the Martian atmospheric environment, which has a lower density than high altitudes.
Paper information:[Scientific Reports] First lift-off and flight performance of a tailless flapping-wing aerial robot in high-altitude environments
