Hindwings of insects as concept generator for hingeless foldable shading systems

Abstract

Hingeless shading systems inspired by nature are increasingly the focus of architectural research. In contrast to traditional systems, these compliant mechanisms can reduce the amount of maintenance-intensive parts and can easily be adapted to irregular, doubly curved, facade geometries. Previous mechanisms rely merely on the reversible material deformation of composite structures with almost homogeneous material properties. This leads to large actuation forces and an inherent conflict between the requirements of movement and the capacity to carry external loads. To enhance the performance of such systems, current research is directed at natural mechanisms with concentrated compliance and distinct hinge zones with high load-bearing capacity. Here, we provide insights into our biological findings and the development of a deployable structure inspired by the Flexagon model of hindwings of insects in general and the hierarchical structure of the wing cuticle of the shield bug (Graphosoma lineatum). By using technical fibre-reinforced plastics in combination with an elastomer foil, natural principles have been partially transferred into a multi-layered structure with locally adapted stiffness. Initial small prototypes have been produced in a vacuum-assisted hot press and sustain this functionality. Initial theoretical studies on test surfaces outline the advantages of these bio-inspired structures as deployable external shading systems for doubly curved facades.

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

“…2 shows the hind wing of H. axyridis and the cross section of the hind wing. The main veins are always on the first half of the hind wing, but the latter half of the hind wing, whose function is folding/unfolding, almost always includes a wing membrane and false veins (Schieber et al, 2017). The hind wing also consists of the epicuticle, mesocuticle, central lamella and exocuticle, and the epicuticle, which is dark purple, is also on the surface of the hind wing (Schieber et al, 2017).…”

“…The main veins are always on the first half of the hind wing, but the latter half of the hind wing, whose function is folding/unfolding, almost always includes a wing membrane and false veins (Schieber et al, 2017). The hind wing also consists of the epicuticle, mesocuticle, central lamella and exocuticle, and the epicuticle, which is dark purple, is also on the surface of the hind wing (Schieber et al, 2017). The cross sections of an artery and vein are composed of the endothelium, tunica intima, tunica media, and tunics adventitia(Meyers et al, 2008).…”

“…To ensure the true nanomechanical properties of the veins, a flat plane is selected for the veins without microtrichia on the dorsal side of the hind wing because membrane wing is composed of the epicuticle, mesocuticle, central lamella and exocuticle, and the epicuticle (Schieber et al, 2017) and the veins are composed of the endothelium, tunica intima, tunica media, and tunics adventitia (Meyers et al, 2008), so the cross section of the hind wing cannot be used to measure the combination property of the hind wing.…”

“…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). The flapping wings of insects are composed of wing membranes and veins (Bao et al, 2011; Schieber et al, 2017). The structure and patterns of the veins of insect wings affect their mechanical properties (Combes, 2003; Meyers et al, 2008).…”

Miniaturization re-establishes symmetry in the wing folding patterns of featherwing beetles

“…Most flying insects have two pairs of wings, but in the majority of known pterygote species only one of these two pairs propels the insects in flight. Several lineages of the Pterygota have evolved various patterns of folding the wings of the pair used for flight 4 , based either on a zig-zag pattern consisting of subparallel folding lines or on an origami-like flexagon pattern consisting of oblique folding lines subdividing the wing blade into triangular facets 5 .…”