Mechanisms of aerial righting in juvenile chukar partridge (Alectoris chukar) were studied from hatching to 14 days-post-hatching (dph). Asymmetric movements of the wings were used from 1 to 8 dph to effect progressively more successful righting behaviour via body roll. Following 8 dph, wing motions transitioned to bilaterally symmetric flapping that yielded aerial righting via nose-down pitch,...

The wing motion in free flight has been described for insects ranging from 1 to 100 mm in wingspan. To support the body weight, the wings typically produce 2-3 times more lift than can be accounted for by conventional aerodynamics. Some insects use the fling mechanism: the wings are clapped together and then flung open before the start of the downstroke, creating a lift-enhancing vortex around ...

For a century, researchers have used the standard lift coefficient C(L) to evaluate the lift, L, generated by fixed wings over an area S against dynamic pressure, ½ρv(2), where v is the effective velocity of the wing. Because the lift coefficient was developed initially for fixed wings in steady flow, its application to other lifting systems requires either simplifying assumptions or complex ad...

The aim of this work is to present a multi-objective optimization method to find maximum efficiency kinematics for a flapping wing unmanned aerial vehicle. We restrained our study to rectangular wings with the same profile along the span and to harmonic dihedral motion. It is assumed that the birdlike aerial vehicle (whose span and surface area were fixed respectively to 1m and 0.15m) is in hor...

A diversity of efficient solutions for flapping flight have evolved in nature; however, it is often difficult to isolate the key characteristics of efficient flapping flight from biological constraints. Rather than base micro aerial vehicle (MAV) design on natural flyers alone, we propose a multi-fidelity computational approach for analysis and design. At the lowest fidelity level, we use a wak...

A finite element flow solver was employed to compute unsteady flow past a three-dimensional Drosophila wing undergoing flapping motion. The computed thrust and drag forces agreed well with results from a previous experimental study. A grid-refinement study was performed to validate the computational results, and a grid-independent solution was achieved. The effect of phasing between the transla...

While the biological flyers often showcase high deformed wing structures, the effects of flexibility on the flapping wing aerodynamics remain inadequately understood. A major challenge in the study of flexible flapping wings is that the resulting wing motion is an outcome of a dynamic balance between the structural dynamics of the wing and the unsteady aerodynamics. Since the effective angle of...

Flapping-wing micro air vehicles (FWMAVs) have the capability of performing various flight modes like birds and insects. Therefore, it is necessary to understand FWMAVs in order fully utilize vehicle. The unique can be studied through trajectory optimization. This paper proposes a optimization framework an FWMAV. A high-fidelity simulation model included sufficiently consider complicated dynami...