Of the insects that have been filmed in flight, those that are 1 mm in length or less often clap their wings together at the end of each upstroke and fling them apart at the beginning of each downstroke. This ;clap and fling' motion is thought to augment the lift forces generated during flight. What has not been highlighted in previous work is that very large forces are required to clap the win...

Although the asymmetry in the upward and downward bending of insect wings is well known, the structural origin of this asymmetry is not yet clearly understood. Some researchers have suggested that based on experimental results, the bending asymmetry of insect wings appears to be a consequence of the camber inherent in the wings. Although an experimental approach can reveal this phenomenon, anot...

A multi-objective optimization (MOO) of two-element wing models with morphing flap by using computational fluid dynamics (CFD) techniques, artificial neural networks (ANN), and non-dominated sorting genetic algorithms (NSGA II), is performed in this paper. At first, the domain is solved numerically in various two-element wing models with morphing flap using CFD techniques and lift (L) and drag ...

The paper presents work on testing of inflatable wings for unmanned aerial vehicles (UAVs). Design and construction of inflatable wings is discussed, along with ground and flight testing. Predictions and correlations of the forces required to warp (twist) the wings to a particular shape and the aerodynamic forces generated by that shape change are presented. The focus is on characterizing the d...

The structure of the dermapteran hind wings is described and their hind wing folding is compared with other insect taxa with folded wings (i.e. Coleoptera, Hymenoptera and Blattodea). The peculiarities of the dermapteran hind wing folding are pointed out: the wings are unfolded by the cerci, one wing after the other, in a rather slow process. The antagonistic movement, folding the wings, is ach...

Infection of North American bats with the keratin-digesting fungus Geomyces destructans often results in holes and ruptures of wing membranes, yet it is unknown whether flight performance and metabolism of bats are altered by such injuries. I conducted flight experiments in a circular flight arena with Myotis albescens and M. nigricans individuals with an intact or ruptured trailing edge of one...

We examined the effect of visual experience on the haptic Müller-Lyer illusion. Subjects made size estimates of raised lines by using a sliding haptic ruler. Independent groups of blind-folded-sighted, late-blind, congenitally blind, and low-vision subjects judged the sizes of wings-in and wings-out stimuli, plain lines, and lines with short vertical ends. An illusion was found, since the wings...

Dragonflies are dramatic, successful aerial predators, notable for their flight agility and endurance. Further, they are highly capable of low-speed, hovering and even backwards flight. While insects have repeatedly modified or reduced one pair of wings, or mechanically coupled their fore and hind wings, dragonflies and damselflies have maintained their distinctive, independently controllable, ...

Recent work on flapping hawkmoth models has demonstrated the importance of a spiral 'leading-edge vortex' created by dynamic stall, and maintained by some aspect of spanwise flow, for creating the lift required during flight. This study uses propeller models to investigate further the forces acting on model hawkmoth wings in 'propeller-like' rotation ('revolution'). Steadily revolving model haw...