Birds demonstrate that flapping-wing flight (FWF) is a versatile flight mode, compatible with hovering, forward flight and gliding to save energy. This extended flight domain would be especially useful on mini-UAVs. However, design is challenging because aerodynamic efficiency is conditioned by complex movements of the wings, and because many interactions exist between morphological (wing area,...

By combining the flapping and rotary motion, a wing rotor (FWR) shows unique kinematics of motion. It can produce significantly higher aerodynamic efficiency lift coefficient than insect-like wings. However, due to lack controllable FWR aerial vehicles, effect different parameters on characteristics remains be evaluated experimentally. In this work, we conduct experimental studies investigate F...

Two styles of bird locomotion, hovering and intermittent flight, have great potential to inform future development of autonomous flying vehicles. Hummingbirds are the smallest flying vertebrates, and they are the only birds that can sustain hovering. Their ability to hover is due to their small size, high wingbeat frequency, relatively large margin of mass-specific power available for flight an...

Flapping-wing kinematics for insect flight has been studied for decades, especially since engineers became interested in flapping-wing micro air vehicles (FWMAVs). Previous work mainly focused on understanding kinematic patterns employed by different insects from the perspective of their trajectories and aerodynamics, and on optimization of kinematic parameters to enhance the understanding. How...

During flight, the wings of many insects undergo considerable shape changes in spanwise and chordwise directions. We determined the origin of spanwise wing deformation by combining measurements on segmental wing stiffness of the blowfly Calliphora vicina in the ventral and dorsal directions with numerical modelling of instantaneous aerodynamic and inertial forces within the stroke cycle using a...

The optimization of a controlled flapping wing micro aerial vehicle for energy-efficient flight in gust using a general, service-oriented framework is investigated. Kinematic (wing-stroke pattern), geometric (wing shape), frequency, and control (state penalty) design variables are considered in a sequence of optimization problems. The service-oriented framework is applied to the integration of ...

In this paper, we suggest a novel transmission for the DC motor-based flapping-wing micro aerial vehicles (FWMAVs). Most FWMAVs employ linkage structures, such as crank-rocker or crank-slider, which are designed to transmit motor’s rotating motion wing’s flapping motion. These transmitting linkages have shown successful performance; however, they entail possibility of mechanical wear originatin...

Thrust generation by flapping is accompanied by alternating pitching moment. On the down-stroke, it pitches the bird down when the wings are above its centre of gravity and up when they are below; on the up-stroke, the directions reverse. Because the thrust depends not only on the flapping characteristics but also on the angle of attack of the bird's body, interaction between the flapping and b...