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E-Mail und die Detektive
(2014)
In diesem Beitrag soll deutlich gemacht werden, an welchen Stellen eines Entwicklungsprozesses Bionik die Entwicklungsarbeit in einem Unternehmen stärken kann. Es werden die Arbeitsabschnitte benannt, in denen der Einsatz von Bionik als besonders erfolgversprechend erachtet wird, und was bei der Durchführung beachtet werden sollte. Darauf aufbauend werden konkrete Methoden benannt, die spezifisch für die Bionik sind, und erläutert, in welchen Arbeitsabschnitten ein Einsatz möglich ist.
Adhesive organs like arolia of insects allow these animals to climb on different substrates by creating high adhesion forces. According to the Dahlquist criterion, arolia must be very soft exhibiting an effective Young's modulus of below 100 kPa to adhere well to different substrates. In previous studies the effective Young´s moduli of adhesive organs were determined using indentation tests yielding their structure to be very soft indeed. However, arolia show a layered structure, thus the values measured by indentation tests comprise the effective Young´s moduli of the whole organs. In this study, a new approach is illustrated to measure the Young´s modulus of the outermost layer of the arolium, i.e. of the epicuticle, of the stick insect Carausius morosus by tensile testing. Due to the inner fibrous structure of the arolium tensile tests allow the characterisation of the overlying epicuticle.
Ventilanordnung und Verfahren zum Kühlen eines Wärmetauschers eines Fahrzeugs [Offenlegungsschrift]
(2023)
Die Erfindung betrifft eine Ventilanordnung umfassend wenigstens ein durch Gas, insbesondere Luft, durchströmbares Ventilelement (1, 1') mit einer Öffnung, wobei der Öffnung ein Dichtelement zugeordnet ist, mit dem die Öffnung verschließbar und/oder öffenbar ist, wobei das Dichtelement durch einen Dichtflächenbereich eines Plattenelements ausgebildet ist, vorzugsweise eines in zumindest einem möglichen Betriebszustand planen Plattenelements ausgebildet ist, wobei das Dichtelement der Öffnung des wenigstens einen Ventilelements gegenüberliegt und der das Dichtelement bildende Dichtflächenbereich des Plattenelements mittels wenigstens eines Spiralarmes mit einem Randflächenbereich des Plattenelements einstückig und relativ zum Randflächenbereich beweglich verbunden ist und der wenigstens eine Spiralarm von wenigstens einer um den Dichtflächenbereich verlaufenden spiralförmigen und durch Gas durchströmbare Ausnehmung in dem Plattenelement zumindest bereichsweise umgeben ist. Die Erfindung betrifft auch ein Verfahren zum Kühlen eines Wärmetauschers in
einem Fahrzeug.
Adhesive organs enable insects to reversibly adhere to substrates even during rapid locomotion. In this process a very fast but reliable change of adhesion and detachment is realised. The stick insect Carausius morosus detaches its adhesive organs by peeling them off the substrate, meaning little areas of the adhesive organs are detached one after another. For such a detachment mechanism low pulling forces are needed. A detachment mechanism as peeling seems also for artificial adhesion devices to be the easiest and the most effortless mechanism for detachment. However, artificial adhesion devices mostly exhibit a solid backing layer preventing effortless peeling. To lift up and detach a small area at the corner of an adhesion device the backing layer has to be tilted, resulting in a deformation of the whole adhesion device, which requires high forces. Subdividing the backing layer into small subunits allows a detachment of a small area at the corner of the adhesion device without deforming the rest of the adhesion device. Thereby, less force is needed to initiate and to complete detachment. To realise an easy detachment of artificial adhesion devices we constructed a holder, which gradually detaches an adhesion device from two sides off the substrate. During normal loading the subunits of the holder interlock with each other so that the pulling force is equally distributed over the whole contact area of the adhesion device ensuring maximal adhesion force. In addition, the holder can be used to increase adhesion during application of the adhesion device. When brought into contact with the substrate with lifted sides, which are lowered subsequently, air trapping is prevented and hence the area of contact can be maximised.
Flying insects employ elegant optical-flow-based strategies to solve complex tasks such as landing or obstacle avoidance. Roboticists have mimicked these strategies on flying robots with only limited success, because optical flow (1) cannot disentangle distance from velocity and (2) is less informative in the highly important flight direction. Here, we propose a solution to these fundamental shortcomings by having robots learn to estimate distances to objects by their visual appearance. The learning process obtains supervised targets from a stability-based distance estimation approach. We have successfully implemented the process on a small flying robot. For the task of landing, it results in faster, smooth landings. For the task of obstacle avoidance, it results in higher success rates at higher flight speeds. Our results yield improved robotic visual navigation capabilities and lead to a novel hypothesis on insect intelligence: behaviours that were described as optical-flow-based and hardwired actually benefit from learning processes.
Earwig wings are highly foldable structures that lack internal muscles. The behaviour and shape changes of the wings during flight are yet unknown. We assume that they meet a great structural challenge to control the occurring deformations and prevent the wing from collapsing. At the folding structures especially, the wing could easily yield to the pressure. Detailed microscopy studies reveal adaptions in the structure and material which are not relevant for folding purposes. The wing is parted into two structurally different areas with, for example, a different trend or stiffness of the wing veins. The storage of stiff or more flexible material shows critical areas which undergo great changes or stress during flight. We verified this with high-speed video recordings. These reveal the extent of the occurring deformations and their locations, and support our assumptions. The video recordings reveal a dynamical change of a concave flexion line. In the static unfolded state, this flexion line blocks a folding line, so that the wing stays unfolded. However, during flight it extends and blocks a second critical folding line and prevents the wing from collapsing. With these results, more insight in passive wing control, especially within high foldable structures, is gained.
The conventional quantitative method for the analysis of inorganic elements in polymer matrices is a complex and time consuming process that presents a significant risk for error. Typically, polymers are digested in a microwave oven or other devices under high temperature and pressure for several hours while employing different mixtures of high purity acids. In many cases, particularly when high concentrations of doped elements are present, the digestion is often incomplete and therefore the reproducibility depends strongly on the type of polymer and additives used. A promising alternative technology that allows for the direct analysis of these polymers without digestion is laser ablation ICP-MS. Due to a lack of available reference materials and the presence of matrix dependent effects, a precise calibration cannot be obtained. In order to compensate for the matrix dependent effects the use of internal standardization is necessary. In this study the correlation between the carbon released during the ablation process and the 13C signal detected by ICP-MS and its use as an internal standard are investigated. For this purpose, twenty-one virgin polymer materials are ablated; the released carbon is determined and correlated with the corresponding integrated 13C signal. The correlation resulted in a direct relationship between the ablated carbon and 13C signal demonstrating the potential ability to neglect at least some of the matrix dependent and transport effects which occur during the laser ablation of virgin polymers.
Fruits (follicles) of Hakea salicifolia and Hakea sericea (Proteaceae) are characterised by pronounced lignification and open via a ventral suture and the dorsal side. The opening along both sides is unique within the Proteaceae. Both serotinous species are obligate seeders, whose spreading benefits from bush fire events. The different tissues and the course of the vascular bundles must allow the opening mechanism. While their 2D-arrangements are known to some extent from light-microscopy images of cross-sections, this work presents their three-dimensional structures and discusses their contribution to the opening of Hakea fruits. For this purpose, 3D greyscale images, reconstructed from µCT-projection data of both fruits are segmented, assisted by a deep learning algorithm (AI algorithm). 3D renderings from these segmentations show strongly interconnected vascular bundles that build a double-dome shaped network in each valve of H. salicifolia and a dome shaped honeycomb-structure in each valve of H. sericea. However, the vascular bundles of both species show no interconnection between the two lateral valves of the fruit but leave gaps for predetermined fracture tissues on the ventral and dorsal side. The opening of the fruits after a fire or after separation from the mother plant can be explained by the anisotropic shrinkage in the two valves of the fruit.