Structure and Mechanical Property of Asio Otus Feather Barbs

Abstract

Avian feather is the outstanding protein fiber structure that still lacks an interpretation generally acceptable in any detail. In this paper, asio otus feathers were morphological represented and their barbs were mechanical characterized by a developed micro-tensile tester with a load resolution of 0.25 mN and a displacement resolution of 10 nm. With a tensile loading speed at 0.02 μm/s, Young’s modulus of the flight feather barbs with length of 1450-1900 μm was calculated to be 3.13-3.66 GPa, higher than 1.47-2.04 GPa for the down feather barbs with length of 520-710 μm. It is concluded that the asio otus’s flight feathers on its wing and tail are more rigid than the down feathers on its body.

Effects of eigen and actual frequencies of soft elastic surfaces on droplet rebound from stationary flexible feather vanes

“…The total elastic system mass m e including the flat surface and spring is equal to the mass of a kingfisher feather, which is approximately 0.01g. The modulus of the feather is approximately 2.5×10 9 Gpa [44][45][46]. The bending style of the flexible feather vane which was fixed at one end in the experiment is as similar as a cantilever, and its stiffness is estimated according to the formula for the stiffness of the cantilever [30], i.e., ,…”

The damping properties of the foam-filled shaft of primary feathers of the pigeon Columba livia

“…The vane consists of numerous barbs aligned parallel to each other, but at some angle to the shaft (Prum 1999 ; Clark 2013). The barbs are loosely connected by the elaborate system of hooklets and, when separated by an external force, they can easily re-establish their connections (Ennos et al 1995 ; Butler and Johnson 2004 ; Kovalev et al 2013 ; Gao et al 2013 ; Chen et al 2016 ; Sullivan et al 2016 ).

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