Effects of multiple vein microjoints on the mechanical behaviour of dragonfly wings: numerical modelling

Abstract

Dragonfly wings are known as biological composites with high morphological complexity. They mainly consist of a network of rigid veins and flexible membranes, and enable insects to perform various flight manoeuvres. Although several studies have been done on the aerodynamic performance of Odonata wings and the mechanisms involved in their deformations, little is known about the influence of vein joints on the passive deformability of the wings in flight. In this article, we present the first three-dimensional finite-element models of five different vein joint combinations observed in Odonata wings. The results from the analysis of the models subjected to uniform pressures on their dorsal and ventral surfaces indicate the influence of spike-associated vein joints on the dorsoventral asymmetry of wing deformation. Our study also supports the idea that a single vein joint may result in different angular deformations when it is surrounded by different joint types. The developed numerical models also enabled us to simulate the camber formation and stress distribution in the models. The computational data further provide deeper insights into the functional role of resilin patches and spikes in vein joint structures. This study might help to more realistically model the complex structure of insect wings in order to design more efficient bioinspired micro-air vehicles in future.

Resilin microjoints: a smart design strategy to avoid failure in dragonfly wings

“…Recent investigations by means of different microscopy techniques have confirmed the occurrence of the resilin in the vein joints of numerous dragonflies78910 and other insect species1112. We have shown numerically that the vein microjoints strongly contribute to the camber formation in flight by increasing the torsional flexibility of the wing5. Hence, it is plausible to hypothesize that the microjoints may have an additional functional significance by avoiding the wing failure under impact.…”

“…Although several parameters influence the deformation of the wings in Odonata, considering their distribution over the wing, vein microjoints have been recognized as one of the most effective elements, in contrast to the others56. Recent investigations by means of different microscopy techniques have confirmed the occurrence of the resilin in the vein joints of numerous dragonflies78910 and other insect species1112.…”

Stiffness distribution in insect cuticle: a continuous or a discontinuous profile?

“…The results obtained from tensile tests on insect wings suggested that the mechanical behaviour of insect cuticle up to fracture can be approximated by a linear elastic material model [22]. Our previous numerical studies have also demonstrated the validity of such an assumption [32,33,[37][38][39][40]. However, consideration of material plasticity is expected to have a crucial role in the realistic prediction of the stress state in insect cuticle subjected to the localized forces due to indentation [25].…”

The roles of wrinkle structures in the veins of Asian Ladybird and bioinspiration

“…Manipulation of the geometry or modulus is an effective method to understand their functions only when the effect of the manipulation on flight performance is appropriately evaluated in detail. The hind wings are always passively deformed to control wing deformations, which can affect the flight performance during flight (Rajabi et al, 2016; Jongerius and Lentink, 2010; Kesel et al, 1998; Mountcastle and Daniel, 2009), so the hind wings has higher flexibility during wind.…”

“…The biomechanical and flight performances are related to the microstructures of insect wings (Wang et al, 2017; Gorb, 1999). Insects can control their wings via active and passive deformations that result in a flexible flight performance (Rajabi et al, 2016; Jongerius and Lentink, 2010; Kesel et al, 1998; Mountcastle and Daniel, 2009). The timely deformations of wings can lead to high lift and improve the distribution of aerodynamic forces on the wing during flight (Hou et al, 2017).…”