Search

Transparent superhydrophobic coatings hold significant potential for applications such as windows and reflectors. However, issues such as fragility and high haze have limited their practicality. Drawing inspiration from dragonfly structures, we developed a transparent superhydrophobic coating by etching the polystyrene microsphere array semiembedded on a silicon oxide matrix and subsequently depositing the methyltrichlorosilane-derived nanofilaments. The resulting coating features silicon oxide craters and nanofilaments inspired by dragonfly wings. Due to the coating's small, multiscale nanostructures, it has a high average visible light transmittance of 90.4% and a low average haze of 4.0%, comparable to the substrate glass. It also exhibits exceptional superhydrophobic properties, with a contact angle of 161.5° and a sliding angle of 1.5°. Notably, the coating retains its superhydrophobicity even after withstanding impacts from 5 kg of water and 500 g of sand, thanks to its robust wing vein-inspired protected structure. Additionally, it shows strong resistance to acids, alkalis, and temperatures up to 400 °C. The coating maintains a high transmittance and low haze after 67 days of UV irradiation or 300 days of outdoor exposure. The combination of low haze and robustness in this transparent superhydrophobic coating highlights its promising potential for applications in related fields.

The work describes the exploration of the design space by fabrication, modelling and testing of bio-based and humidity-triggered 4D printed shape-changing biocomposites. The aim is to broaden the understanding of the control actuation via printing path tailoring and unlock new potential applications for biomaterials and autonomous actuator design. The composites are made with continuous flax yarns and polylactic acid matrix filaments and exhibit moisture-induced actuation. The actuation capability is first demonstrated by printing a calla lily flower-inspired configuration subjected to 98% relative humidity. This structure did not however achieve the anticlastic double curvature and large actuation targeted. To resolve these issues, cross-ply composite architectures with bent filaments deposited in one layer have then been developed. The amplitude for curvature control ranges obtained were 1.9*10−3mm−1 and 7.9*10−3mm−1 depending on the position on the specimen. Other cross-ply hygromorphs solutions are also proposed, with the orientation of their passive layers ([0°]2) tilted by α degrees (stacking sequence: [-α,α, 90°]). The largest actuation curvature was obtained when α=40°, which increased by 0.0072 mm−1 when compared to α = 0°. The hygromorphs presented in this work are modelled using in an in–house filament scale finite element model able to capture the complexity of the printed hygromorphs architectures.

A bio-inspired, plant-derived polyphenol, tannic acid (TA) was identified as a renewable admixture to improve the compressive strength of concretes. Aiming to understand the underlying mechanism responsible for this strength improvement, this study examines how TA mediates the hydration of tricalcium silicate (alite). Experimental study shows that TA can form complex with calcium ions through chelating, retarding the hydration of the alite and changing of the hydration products. Particularly, X-ray diffraction analysis shows that TA makes calcium hydroxide preferentially grow on the [001] face. Fourier-transform infrared spectroscopy and 29Si MAS NMR results reveal that the mean chain length of calcium silicate hydrate (CSH) is reduced by TA. More importantly, mercury intrusion porosimetry testing reveals that pores with size near 30 nm was almost eliminated by adding TA, leading to higher elastic modulus of the produced CSH and higher compressive strength of the produced concrete.

The lateral line system of fishes provides cues for collective behaviour, such as shoaling, but it remains unclear how anatomical lateral line variation leads to behavioural differences among species. Here we studied associations between lateral line morphology and collective behaviour using two morphologically divergent species and their second-generation hybrids. We identify collective behaviours associated with variation in canal and superficial lateral line morphology, with closer proximities to neighbouring fish associated with larger canal pore sizes and fewer superficial neuromasts. A mechanistic understanding of the observed associations was provided by hydrodynamic modelling of an artificial lateral line sensor, which showed that simulated canal-based neuromasts were less susceptible to saturation during unidirectional movement than simulated superficial neuromasts, while increasing the canal pore size of the simulated lateral line sensor elevated sensitivity to vortices shed by neighbouring fish. Our results propose a mechanism behind lateral line flow sensing during collective behaviour in fishes.

Bird tails play a key role in aerodynamics and flight stability. They produce extra lift for takeoff and landing maneuvers, enhance wing functions and maintain stability during flight (keeping the bird from yawing, rolling and pitching, or otherwise losing control). This paper investigates the use of bioinspired horizontal stabilizers for Micro Air Vehicles (MAVs) involving a Zimmerman wing-body geometry. A selection of five tail shapes of the main types existing in nature is presented, and a parametric analysis is conducted looking into the influence of the most relevant tail geometric parameters to increase the longitudinal static stability of the vehicle. Based on the parametric study, a smaller subset of candidate tail designs are shortlisted to perform a detailed aerodynamic analysis. Then, steady RANS CFD simulations are conducted for a higher-fidelity study of these candidate tail designs to obtain an optimum of each tail type. The criterion for selection of the optimum tail configuration is the maximum aerodynamic efficiency, CLCD , as well as a high longitudinal static stability. The squared-fan tail provides the highest aerodynamic efficiency while maintaining a high longitudinal stability of the vehicle. In conclusion, this paper provides an innovative study of improving longitudinal stability and aerodynamics through the implementation of bioinspired horizontal stabilizers in vehicles with these characteristics.

Load-bearing biological materials employ specialized elastic bridging regions to connect material parts with substantially different properties. While such bridging regions emerge in diverse systems of biological systems, their functional–mechanical origins are yet disclosed. Here, we hypothesize that these elastic bridging regions evolved primarily to minimize the near-interface stress effects in the biological material and, supported by experiments and simulations, we develop a simple theoretical model for such stress-minimizing bridging modulus. Our theoretical model describes well extensive experimental data of diverse biomechanical systems, suggesting that despite their compositionally distinct bridging regions, they share a similar mechanical adaptation strategy for stress minimization. The theoretical model developed in this study may directly serve as a design guideline for bio-inspired materials, biomedical applications, and advanced interfacial architectures with high resilience to mechanical failure. Biological materials exhibit unconventional structural-mechanical strategies allowing them to attain extreme load-bearing capabilities. Here, we identify the strategy of biological materials to connect parts of distinct elastic properties in an optimal manner of stress minimization. Our findings are compatible with broad types of biological materials, including biopolymers, biominerals, and their bio-composite combinations, and may promote novel engineering designs of advanced biomedical and synthetic materials. [Display omitted] [ABSTRACT FROM AUTHOR]

Dip catalysts are attracting interest in both academia and industry for catalyzing important chemical reactions. These provide excellent stability, better recoverability, recyclability, and easy scale-up. Using the unique microstructures of leaf skeletons, we present a fractal-like hierarchical surface that can be used as a versatile and efficient dip catalyst. Copper oxide microcactuses with nanoscalar features were fabricated onto the Bauhinia racemosa leaf skeletons via a combination of physical vapor deposition, electroplating, and chemical oxidation methods. The coated leaf skeletons have a very high surface area, and the three-dimensional (3D) morphology allows the reactants to encounter the catalytic sites efficiently and move around the reaction mixture swiftly. The fabricated bioinspired leaf skeleton-based dip catalyst was characterized and demonstrated to be very efficient for alcohol dehydrogenation reaction, examined under different experimental conditions. A ceramic 3D-printed catalyst holder was designed to hold the catalysts to avoid any damage caused by the magnetic bars during the reactions. The performance is determined using the reaction yields, and the efficiencies are correlated with microcactus-like structures composed of CuO and the 3D fractal-like shape provided by the leaf skeleton. This strategy can be applied to fabricate other dip catalysts using different materials and designs, suitable for catalyzing numerous other chemical reactions. [ABSTRACT FROM AUTHOR]

Thin films are ideal building blocks for hyperacute sensors and flexible electronic devices. However, most thin films either lack strength for practical applications or are not compatible with mass-production processes. Here, we reported an orb-web-inspired polymer-carbon nanocomposite-based, strong, lightweight, flexible mesh-type film that was compatible with standard microfabrication and suitable for high-performance acoustic sensing. Taking advantage of the superior mechanical strength of the three-dimensional (3D) heterogeneous nanocomposites constructed by one-dimensional (1D), two-dimensional (2D) carbon-based nanoparticles and polymer matrixes, we fabricated a 564-nm-thick mesh-type film that could be suspended freely both in liquid and air, and folded and stretched repeatedly over a macroscale opening. The sensing application of the mesh-type nanocomposite film was further demonstrated, which could even detect weak airborne sound waves with high fidelity, large dynamic range (>115 dB), and fine frequency resolution (<0.05 Hz) over the audible range. This work provides an approach to manufacturing designable, thin film-based flexible devices across scales with superior performance. [ABSTRACT FROM AUTHOR]

High-tech sensors, energy harvesters, and robots are increasingly being developed for operation on plant leaves. This introduces an extra load which the leaf must withstand, often under further dynamic forces like wind. Here, we took the example of mechanical energy harvesters that consist of flat artificial "leaves" fixed on the petioles of N. oleander, converting wind energy into electricity. We developed a combined experimental and computational approach to describe the static and dynamic mechanics of the natural and artificial leaves individually and join them together in the typical energy harvesting configuration. The model, in which the leaves are torsional springs with flexible petioles and rigid lamina deforming under the effect of gravity and wind, enables us to design the artificial device in terms of weight, flexibility, and dimensions based on the mechanical properties of the plant leaf. Moreover, it predicts the dynamic motions of the leaf--artificial leaf combination, causing the mechanical-to-electrical energy conversion at a given wind speed. The computational results were validated in dynamic experiments measuring the electrical output of the plant-hybrid energy harvester. Our approach enables us to design the artificial structure for damage-safe operation on leaves (avoiding overloading caused by the interaction between leaves and/or by the wind) and suggests how to improve the combined leaf oscillations affecting the energy harvesting performance. We furthermore discuss how the mathematical model could be extended in future works. In summary, this is a first approach to improve the adaptation of artificial devices to plants, advance their performance, and to counteract damage by mathematical modelling in the device design phase. [ABSTRACT FROM AUTHOR]

Designs perfected through evolution have informed bioinspired animal‐like robots that mimic the locomotion of cheetahs and the compliance of jellyfish; biohybrid robots go a step further by incorporating living materials directly into engineered systems. Bioinspiration and biohybridization have led to new, exciting research, but humans have relied on biotic materials—non‐living materials derived from living organisms—since their early ancestors wore animal hides as clothing and used bones for tools. In this work, an inanimate spider is repurposed as a ready‐to‐use actuator requiring only a single facile fabrication step, initiating the area of "necrobotics" in which biotic materials are used as robotic components. The unique walking mechanism of spiders—relying on hydraulic pressure rather than antagonistic muscle pairs to extend their legs—results in a necrobotic gripper that naturally resides in its closed state and can be opened by applying pressure. The necrobotic gripper is capable of grasping objects with irregular geometries and up to 130% of its own mass. Furthermore, the gripper can serve as a handheld device and innately camouflages in outdoor environments. Necrobotics can be further extended to incorporate biotic materials derived from other creatures with similar hydraulic mechanisms for locomotion and articulation. [ABSTRACT FROM AUTHOR]

Biological organisms present marvelous morphing behaviors from the quiescent blooming of flowers to the energetic wing‐flapping of birds that have always inspired humans to design better‐engineered products. The diversity of natural motion is attributed primarily to the intricate and hierarchical structure of actuators that are self‐assembled from nanoscale structures to superstructures. Compared to the biological actuators, their manmade counterparts, often with significantly limited capabilities, are fabricated from various materials with relatively simple structures using limited fabrication techniques. With the rapid developments in technologies that require soft robotics and human‐machine interfaces, there is increasing demand for soft actuators with improved capabilities such as larger output force, repeatability, and a more comprehensive range of motion. Biological actuators provide critical insights into the structure‐function relationship and offer exciting concepts to advance the science and technology of artificial soft actuators. Here, the design approaches found in natural actuation systems are discussed from the nanoscale to the highest levels in the structural hierarchy and the physical principles involved in their diverse actuation capabilities. In that context, finally, the fabrication techniques that have been utilized for manmade soft actuators, with a focus on the advantages, challenges, and concepts for potential future developments are reviewed. [ABSTRACT FROM AUTHOR]

The horse hoof wall exhibits exceptional impact resistance and fracture control due to its unique hierarchical structure which contains tubular, lamellar, and gradient configurations. In this study, structural characterization of the hoof wall was performed revealing features previously unknown. Prominent among them are tubule bridges, which are imaged and quantified. The hydration-dependent viscoelasticity of the hoof wall is described by a simplified Maxwell-Weichert model with two characteristic relaxation times corresponding to nanoscale and mesoscale features. Creep and relaxation tests reveal that the specific hydration gradient in the hoof keratin likely leads to reduced internal stresses that arise from spatial stiffness variations. To better understand realistic impact modes for the hoof wall in-vivo , drop tower tests were executed on hoof wall samples. Fractography revealed that the hoof wall's reinforced tubular structure dominates at lower impact energies, while the intertubular lamellae are dominant at higher impact energies. Broken fibers were observed on the surface of the tubules after failure, suggesting that the physically intertwined nature of the tubule reinforcement and intertubular matrix improves the toughness of this natural fiber reinforced composite. The augmented understanding of the structure-mechanical property relationship in dynamic loading led to the design of additively manufactured bioinspired structures, which were evaluated in quasistatic and dynamic loadings. The inclusion of gradient structures and lamellae significantly reduced the damage sustained in drop tower tests, while tubules increased the energy absorption of samples tested in compact tension. The samples most similar to the hoof wall displayed remarkably consistent fracture control properties. The horse hoof wall, capable of withstanding large, repeated, dynamic loads, has been touted as a candidate for impact-resistant bioinspiration. However, our understanding of this biological material and its translation into engineered designs is incomplete. In this work, new features of the horse hoof wall are quantified and the hierarchical failure mechanisms of this remarkable material under near-natural loading conditions are uncovered. A model of the hoof wall's viscoelastic response, based on studies of other keratinous materials, was developed. The role of hydration, strain rate, and impact energy on the material's response were elucidated. Finally, multi-material 3D printed designs based on the hoof's meso/microstructure were fabricated and exhibited advantageous energy absorption and fracture control relative to control samples. [Display omitted] [ABSTRACT FROM AUTHOR]

Bacterial nanocellulose (BNC) is usually produced as randomly‐organized highly pure cellulose nanofibers films. Its high water‐holding capacity, porosity, mechanical strength, and biocompatibility make it unique. Ordered structures are found in nature and the properties appearing upon aligning polymers fibers inspire everyone to achieve highly aligned BNC (A‐BNC) films. This work takes advantage of natural bacteria biosynthesis in a reproducible and straightforward approach. Bacteria confined and statically incubated biosynthesized BNC nanofibers in a single direction without entanglement. The obtained film is highly oriented within the total volume confirmed by polarization‐resolved second‐harmonic generation signal and Small Angle X‐ray Scattering. The biosynthesis approach is improved by reusing the bacterial substrates to obtain A‐BNC reproducibly and repeatedly. The suitability of A‐BNC as cell carriers is confirmed by adhering to and growing fibroblasts in the substrate. Finally, the thermal conductivity is evaluated by two independent approaches, i.e., using the well‐known 3ω‐method and a recently developed contactless thermoreflectance approach, confirming a thermal conductivity of 1.63 W mK−1 in the direction of the aligned fibers versus 0.3 W mK−1 perpendicularly. The fivefold increase in thermal conductivity of BNC in the alignment direction forecasts the potential of BNC‐based devices outperforming some other natural polymer and synthetic materials. [ABSTRACT FROM AUTHOR]

Controlled, reversible attachment is widely spread throughout the animal kingdom: from ticks to tree frogs, whose weights span from 2 mg to 200 g, and from geckos to mosquitoes, who stick under vastly different situations, such as quickly climbing trees and stealthily landing on human hosts. A fascinating and complex interplay of adhesive and frictional forces forms the foundation of attachment of these highly diverse systems to various substrates. In this review, we present an overview of the techniques used to quantify the adhesion and friction of terrestrial animals, with the aim of informing future studies on the fundamentals of bioadhesion, and motivating the development and adoption of new or alternative measurement techniques. We classify existing methods with respect to the forces they measure, including magnitude and source, i.e., generated by the whole body, single limbs, or by sub-structures. Additionally, we compare their versatility, specifically what parameters can be measured, controlled, and varied. This approach reveals critical trade-offs of bioadhesion measurement techniques. Beyond stimulating future studies on evolutionary and physicochemical aspects of bioadhesion, understanding the fundamentals of biological attachment is key to the development of biomimetic technologies, from soft robotic grippers to gentle surgical tools. [ABSTRACT FROM AUTHOR]

The lack of drinkable water is one of the most significant risks for the future of the humanity. Estimates show that in the near future, this risk will become the origin of massive migrations leading to humanitarian disaster. As consequence, the development of solutions to provide water is becoming ever more critical, and a significant effort is devoted to identifying new sources of water. Among the developed strategies, fog harvesting, which takes advantage of atmospheric water to provide potable water, is a solution of interest due to its potential in sustainable development. Unfortunately, this approach suffers from low yield. In the present work, we take inspiration from living species to design and elaborate surfaces with high potential for water harvesting applications. This work takes advantage of 3D-printing and post-printing functionalization to elaborate a strategy that allows modelling, printing, and functionalization of surfaces to yield parahydrophobic behavior. The roughness and surface morphology of the prepared surfaces were investigated. These characteristics were then related to the observed wettability and potential of the functionalized interfaces for water harvesting applications. This work highlights significant variations in surface wettability via surface modification; strong hydrophobic behavior was observed via modification with linear carboxylic acids particularly for surfaces bearing vertical blades (plate with vertical blades and grid with vertical blades). [ABSTRACT FROM AUTHOR]

The field of plant-inspired robotics is based on principles underlying the movements and attachment and adaptability strategies of plants, which together with their materials systems serve as concept generators. The transference of the functions and underlying structural principles of plants thus enables the development of novel life-like technical materials systems. For example, principles involved in the hinge-less movements of carnivorous snap-trap plants and climbing plants can be used in technical applications. A combination of the snap-trap motion of two plant species (Aldrovanda vesiculosa and Dionaea muscipula) has led to the creation of a novel motion sequence for plant-inspired robotics in an artificial Venus flytrap system, the Venus Flyflap. The novel motion pattern of Venus Flyflap lobes has been characterized by using four state-of-the-art actuation systems. A kinematic analysis of the individual phases of the new motion cycle has been performed by utilizing precise pneumatic actuation. Contactless magnetic actuation augments lobe motion into energy-efficient resonance-like oscillatory motion. The use of environmentally driven actuator materials has allowed autonomous motion generation via changes in environmental conditions. Measurement of the energy required for the differently actuated movements has shown that the Venus Flyflap is not only faster than the biological models in its closing movement, but also requires less energy in certain cases for the execution of this movement. [ABSTRACT FROM AUTHOR]

In biomimetic design, functional systems, principles, and processes observed in nature are used for the development of innovative technical systems. The research on functional features is often carried out without giving importance to the generative mechanism behind them: evolution. To deeply understand and evaluate the meaning of functional morphologies, integrative structures, and processes, it is imperative to not only describe, analyse, and test their behaviour, but also to understand the evolutionary history, constraints, and interactions that led to these features. The discipline of palaeontology and its approach can considerably improve the efficiency of biomimetic transfer by analogy of function; additionally, this discipline, as well as biology, can contribute to the development of new shapes, textures, structures, and functional models for productive and generative processes useful in the improvement of designs. Based on the available literature, the present review aims to exhibit the potential contribution that palaeontology can offer to biomimetic processes, integrating specific methodologies and knowledge in a typical biomimetic design approach, as well as laying the foundation for a biomimetic design inspired by extinct species and evolutionary processes: Paleomimetics. A state of the art, definition, method, and tools are provided, and fossil entities are presented as potential role models for technical transfer solutions. [ABSTRACT FROM AUTHOR]

Bio-inspired design (BID) means the concept of transferring functional principles from biology to technology. The core idea driving BID-related work is that evolution has shaped functional attributes, which are termed "adaptations" in biology, to a high functional performance by relentless selective pressure. For current methods and tools, such as data bases, it is implicitly supposed that the considered biological models are adaptations and their functions already clarified. Often, however, the identification of adaptations and their functional features is a difficult task which is not yet accomplished for numerous biological structures, as happens to be the case also for various organismic features from which successful BID developments were derived. This appears to question the relevance of the much stressed importance of evolution for BID. While it is obviously possible to derive an attractive technical principle from an observed biological effect without knowing its original functionality, this kind of BID ("analog BID") has no further ties to biology. In contrast, a BID based on an adaptation and its function ("homolog BID") is deeply embedded in biology. It is suggested that a serious and honest clarification of the functional background of a biological structure is an essential first step in devising a BID project, to recognize possible problems and pitfalls as well as to evaluate the need for further biological analysis. [ABSTRACT FROM AUTHOR]

Copyright of Cuadernos del Centro de Estudios de Diseño y Comunicación is the property of Cuadernos del Centro de Estudios de Diseno y Comunicacion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Cuadernos del Centro de Estudios de Diseño y Comunicación is the property of Cuadernos del Centro de Estudios de Diseno y Comunicacion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Cuadernos del Centro de Estudios de Diseño y Comunicación is the property of Cuadernos del Centro de Estudios de Diseno y Comunicacion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Cuadernos del Centro de Estudios de Diseño y Comunicación is the property of Cuadernos del Centro de Estudios de Diseno y Comunicacion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Through hundreds of millions of evolution, animals and plants have possessed their unique structures to adapt to natural variations. As a familiar process, liquid transportation plays an important part in both production and life, and researchers focus on how to achieve this process in a convenient and efficient way without energy input. Inspired by nature, various bioinspired structures are reported and have won multiple achievements. This review starts from basic theory about surface wettability, and then summarises the creatures with special liquid transport functions as well as crucial structures that cause this phenomenon. Next, the recent articles about transporting liquid by bioinspired materials are introduced. Finally, we proposed a brief conclusion and the prospect of bionic materials in the future. [ABSTRACT FROM AUTHOR]

Bioinspired, highly flexible, fast, and biodegradable heaters are fabricated based on Ag nanowires and leaf skeletons of different plant species. The leaf skeletons act as transparent substrates with a high surface‐area‐to‐volume ratio and allow a uniform dispersion of the Ag nanowires through the surface. Ag nanowires adhered to the leaf skeletons display very good transmittance (up to ≈87%) and mechanical (flexibility) properties (curvature values >800 m−1) without any post‐treatment. The flexible leaf skeleton‐based heaters reach high temperatures very quickly, with very low voltages (<4 V). The performance of the bioinspired heater surface is dependent on the types of fractal structures at the microscale. The morphology of the leaf skeletons is studied in detail and is corelated with the transmittance, flexibility, and sheet resistances. Bioinspired heater surfaces based on different leaf skeletons are compared based on their multiscale morphology, and the different heating performance parameters are screened. Based on the study conducted, insights on the best‐performing biotic design for the fabrication of the heaters that are useful in practical wearable, medical, or industrial heating applications are provided. [ABSTRACT FROM AUTHOR]

Compliant joints own their motion performance to three main aspects: base material, geometrical design, and dimensions. When aiming to increase their motion range without affecting the overall assembly of the system in which they are employed, modifying the design or dimensions is not appropriate anymore. To overcome this, the current work presents a novel strategy for increasing the motion range of the split tube flexural pivots joint based on removing material from the complaint joint using two specific bio-inspired patterns. These bio-inspired patterns are based on the shells encountered in Testudines (tortoise) and Dasypodidae (armadillo). Then, these patterns were parametrized, and their effective mechanical properties evaluated on 3D printed samples. Features of the flexible region of the flexural pivot joint were varied to identify the conditions in which the motion range increases. A factorial analysis was made to obtain the angular displacement response based on the determined parameters, which depend on the flexible region features. The use of these patterns successfully demonstrated the reduction in stiffness of the joints, obtaining increments in displacements twice in the stiffest case and 4.25 times in the most flexible one. Secondary displacements were also analyzed. Displacements measured were characterized via computationally analyzed images and recordings. Finally, the mechanical properties measured were compared to computationally predicted properties via Finite Element Models. Predictions resulted in good agreement with the experimental measurements with errors below 10% in most cases and up to 15% in the worst cases. These were attributed to manufacturing defects in the samples.

Flying insects are capable of hovering and rapid maneuver under unpredictable environments. The principal wing-beat is generated by transmitting the rhythmical contractions of power muscles to the exoskeleton and wing-base articulation. Fine-tuning of the flapping wing kinematics is achieved by deforming the articulation with tiny steering muscles. This flapping mechanism of insect flight is distinct from that of conventional man-made aerial vehicles, enabling superior flight. In this study, we propose an insect-inspired flapping mechanism, which is comprised of two different types of actuators and a flexible wing-base structure. The flapping mechanism is driven by electric motors, which modulate wing kinematics by adjusting the flexible wing-base structure using electromagnetic actuators (EMAs). First, the EMA design was optimized based on analysis of the dynamic forces and displacements to enable deformations of the wing-base structure. A prototype flapping mechanism was then constructed, and its performance was evaluated experimentally by adjusting the actuation phase of the EMAs being synchronized with flapping motions of the wing. The results indicate that the wingbeat kinematics and aerodynamic performance are noticeably sensitive to the actuation timing of EMAs and can thus be controlled by tuning the EMA actuating timing and direction. The flapping mechanism can potentially be applied as a novel means for controlling body posture of flapping-wing micro air vehicles to achieve insect-inspired stable flights in natural environments.

High-tech sensors, energy harvesters, and robots are increasingly being developed for operation on plant leaves. This introduces an extra load which the leaf must withstand, often under further dynamic forces like wind. Here, we took the example of mechanical energy harvesters that consist of flat artificial “leaves” fixed on the petioles of N. oleander, converting wind energy into electricity. We developed a combined experimental and computational approach to describe the static and dynamic mechanics of the natural and artificial leaves individually and join them together in the typical energy harvesting configuration. The model, in which the leaves are torsional springs with flexible petioles and rigid lamina deforming under the effect of gravity and wind, enables us to design the artificial device in terms of weight, flexibility, and dimensions based on the mechanical properties of the plant leaf. Moreover, it predicts the dynamic motions of the leaf–artificial leaf combination, causing the mechanical-to-electrical energy conversion at a given wind speed. The computational results were validated in dynamic experiments measuring the electrical output of the plant-hybrid energy harvester. Our approach enables us to design the artificial structure for damage-safe operation on leaves (avoiding overloading caused by the interaction between leaves and/or by the wind) and suggests how to improve the combined leaf oscillations affecting the energy harvesting performance. We furthermore discuss how the mathematical model could be extended in future works. In summary, this is a first approach to improve the adaptation of artificial devices to plants, advance their performance, and to counteract damage by mathematical modelling in the device design phase.

We present EMBUR—EMerita BUrrowing Robot—the first legged robot inspired by the Pacific mole crab, Emerita analoga, capable of burrowing vertically downward. We choose Emerita analoga as a model organism for its rapid downward burrowing behaviors, as it is four times as fast as the most rapid bivalve mollusk. Vertical burrowing in granular media is a challenging endeavor due to the tendency for the media to create upwards resistive forces on an intruder, even during purely horizontal motions. Our robot is capable of vertically burrowing its body in granular substrate primarily through excavation using two leg pairs, which are functionally analogous to groupings of leg pairs of the mole crab. We implement a novel leg mechanism with a sweeping trajectory, using compliant fabric to enable an anisotropic force response. The maximum resistive force during the power stroke is 6.4 times that of the return stroke. We compare robot body pitch and spatial trajectories with results from biomechanical studies of the mole crabs. We characterize the sensitivity of the robot to initial depth, body pitch and leg pose, and propose bounds on initial conditions which predict various burrowing failure modes. Parametric studies utilizing Granular Resistive Force Theory inform our understanding of robot behavior in response to leg phasing and orientation. Not only does this robotic platform represent the first robophysical model of vertical mole crab-inspired burrowing, it is also one of the first legged, primarily excavative small-scale burrowing agents.

The dynamic, interconnected nature of modern supply chains makes it important to understand how firm-level decision-making will impact the robustness of supply chains to disruption. The behavior of naturally evolved distribution systems offers a useful starting point to identify potential design features that can promote robustness without compromising the viability of individual firms. Drawing inspiration from how ant food-sharing networks respond to supply shortages, we developed an agent-based model of a generalized supply network and evaluated how different local strategies influenced the ability of firms to acquire sufficient resources to meet their demand. Our simulations reveal that differences among firms in strategic behavior can reduce variation in outcomes across firms while maintaining mean performance, thereby buffering system-level robustness. In addition, the ability to expand one's supplier network bolstered performance when firms experienced difficulty in meeting their demand. Conversely, under the assumptions of our model, overly relying on distributors to gain access to additional suppliers or to gain competitive advantages was ineffective in helping firms to meet their consumptive demand. Our nature-inspired modeling framework provides a potentially useful approach for evaluating how different participant decision-making strategies may impact the robustness and resilience of global supply chains that are increasingly likely to face frequent and unpredictable disruptions. [ABSTRACT FROM AUTHOR]

• A symmetrical leech-inspired soft robot is developed. • The robot could achieve a velocity of up to 22.66 mm/s under 45 Gauss conditions. • The robot is capable of carrying loads, crossing obstacles, and performing specific tasks. In this study, we present a symmetrical leech-inspired soft robot that employs a magnetic actuation system for precise movement control. The robot weighs only 1.17 g and has a symmetrical micro-concave structure that maintains a stable kinematic posture during high-frequency motion. The gravity generated by the magnets is used to simulate the attraction of the two suckers of the leech. The experimental results show that the micro-concave structure is designed to achieve a robot velocity of up to 22.66 mm/s under 45 Gauss conditions, which is a better kinematic performance compared to the single symmetric structure (with a velocity of 13.2 mm/s). According to our experiments testing the robot in different motion modes, it has shown the ability to stably climb over obstacles, transport objects, and detect solutions, demonstrating its potential for diverse applications in healthcare, emergency rescue, and environmental monitoring. [ABSTRACT FROM AUTHOR]

Lionfishes are recognized as invasive and predatory species in the world. The genus Pterois belongs to the Scorpaenidae family has 10 confirmed species. Among them, two species Pterois miles and P. volitans were reported as non-indigenous species in Turkish marine waters. Although dorsal, pelvic, and anal fins of lionfish have venom-releasing spines which can have systemic effects such as severe pain, fever, vomiting, and dizziness, there are no reports of death by lionfish in the literature anyway. After careful removal of the venomous spines, lionfish meat is suitable for human consumption. The bioactivity of homogenates obtained from the venomous spines of lionfish has been the subject of various research since the 1950s. Until now, it has been proven that the venomous spines of the lionfish contain anticancer, antiviral, anti-inflammatory, anticoagulant, antioxidant, and antibacterial compounds and can be used in biomedical applications as a natural resource of marine origin. Moreover, the spine shape of lionfish has provided inspiration that can be useful in designing reusable syringe needles and sterilizable plungers, thereby reducing biomedical waste and sharps disposal costs. Additionally, the fins and spines of lionfish, which are typically removed and discarded, are used to make jewellery. This review, therefore, focused on evaluating alternative management actions to bring these invasive fish into the economy and control their populations, owing to both their use in biomedical fields and their suitability for bioinspiration. [ABSTRACT FROM AUTHOR]

The behaviour of triazolylidene ligands coordinated at a {Fe2(CO)5(µ-dithiolate)} core related to the active site of [FeFe]-hydrogenases have been considered to determine whether such carbenes may act as redox electron-reservoirs, with innocent or non-innocent properties. A novel complex featuring a mesoionic carbene (MIC) [Fe2(CO)5(Pmpt)(µ-pdt)] (1; Pmpt = 1-phenyl-3-methyl-4-phenyl-1,2,3-triazol-5-ylidene; pdt = propanedithiolate) was synthesized and characterized by IR, 1H, 13C{1H} NMR spectroscopies, elemental analyses, X-ray diffraction, and cyclic voltammetry. Comparison with the spectroscopic characteristics of its analogue [Fe2(CO)5(Pmbt)(µ-pdt)] (2; Pmbt = 1-phenyl-3-methyl-4-butyl-1,2,3-triazol-5-ylidene) showed the effect of the replacement of a n-butyl by a phenyl group in the 1,2,3-triazole heterocycle. A DFT study was performed to rationalize the electronic behaviour of 1, 2 upon the transfer of two electrons and showed that such carbenes do not behave as redox ligands. With highly perfluorinated carbenes, electronic communication between the di-iron site and the triazole cycle is still limited, suggesting low redox properties of MIC ligands used in this study. Finally, although the catalytic performances of 2 towards proton reduction are weak, the protonation process after a two-electron reduction of 2 was examined by DFT and revealed that the protonation process is favoured by S-protonation but the stabilized diprotonated intermediate featuring a {Fe-H⋯H-S} interaction does not facilitate the release of H2 and may explain low efficiency towards HER (Hydrogen Evolution Reaction). [ABSTRACT FROM AUTHOR]

This article proposes a 3 D printed bioinspired cellular structure known as Scutoids for use in lightweight sandwich designs under compression loads. The 3 D Scutoid cells are epithelial cell that are known for the property of stabilised tissue packing. Four self-packing Scutoid cells are designed for a cellular structure and investigated for deformation, crushing profile, stress concentration, and forces to assess its energy absorption capabilities at various crushing velocities using Aluminium alloy as material in ABAQUS/Explicit. Further, the effect of position of transition point that forms as a result of cell intercalation process along the apico-basal axis on the deformation is also studied by generating different Scutoid cell motifs. The performance of the Scutoid structure is compared to conventional honeycomb with similar mass and surface area. The suitability of the four-cell bioinspired Scutoid motif as a precursor to generate a sandwich structure is discussed by reproducing the cells. [ABSTRACT FROM AUTHOR]

Spatial variations in fiber alignment (and, therefore, in mechanical anisotropy) play a central role in the excellent toughness and fatigue characteristics of many biological materials. In this work, we examine the effect of fiber alignment in soft composites, including both “in-plane” and “out-of-plane” fiber arrangements. We take inspiration from the spatial variations of fiber alignment found in the aorta to three-dimensionally (3D) print soft, tough silicone composites with an excellent combination of stiffness, toughness, and fatigue threshold, regardless of the direction of loading. These aortainspired composites exhibit mechanical properties comparable to skin, with excellent combinations of stiffness and toughness not previously observed in synthetic soft materials. [ABSTRACT FROM AUTHOR]

Nature is a source of diverse materials, including polysaccharides, which have been used to improve the quality of life. Besides being abundant and renewable, polysaccharides possess many advantages, such as biodegradability and biocompatibility, which allow them to be applied in different fields. They can be used in the design and development of renewable materials, thus contributing to a more sustainable society. Because of their advantages and versatility, polysaccharides may be incorporated in many systems, particularly biomimetic ones, to create outstanding sustainable solutions to problems that still need to be solved. Hence, nature not only offers resources but an inspiration to overcome issues. In this sense, this work aims to present an overview of current relevant biomimetic systems based on polysaccharides. Chitosan, cellulose, xanthan gum, alginates, pullulan, hyaluronic acid, schizophyllan, and oligomeric cyclodextrins are covered. The application of these polysaccharides in the design of biosensors, systems for environmental remediation, structural materials, drug delivery systems, tissue engineering among others is described. Finally, the challenges that still need to be faced and opportunities of application of these materials for the development of bioinspired technologies in the next future are highlighted. [ABSTRACT FROM AUTHOR]

The paper is focused on the methods for the emulation of biomimetic properties of wood by creating a database of abstracted design principles into a form understandable for designers. The database was created according to the proposed procedure. It can serve as a tool for introducing the nature as a model, a mentor, a pattern, and as a measure for the development of innovative sustainable solutions in different areas of design. Designers will be able to use the database in a visually understandable and graphically elaborated form of insights into nature and instructions on how to use its perfectly functional creations, like reference models of what works and what can be applicable to their solutions. [ABSTRACT FROM AUTHOR]

Mosquitoes are commonly viewed as pests and deadly predators by humans. Despite this perception, investigations of their survival-based behaviors, select anatomical features, and biological composition have led to the creation of several beneficial technologies for medical applications. In this review, we briefly explore these mosquito-based innovations by discussing how unique characteristics and behaviors of mosquitoes drive the development of select biomaterials and medical devices. Mosquito-inspired microneedles have been fabricated from a variety of materials, including biocompatible metals and polymers, to mimic of the mouthparts that some mosquitoes use to bite a host with minimal injury during blood collection. The salivary components that these mosquitoes use to reduce the clotting of blood extracted during the biting process provide a rich source of anticoagulants that could potentially be integrated into blood-contacting biomaterials or administered in therapeutics to reduce the risk of thrombosis. Mosquito movement, vision, and olfaction are other behaviors that also have the potential for inspiring the development of medically relevant technologies. For instance, viscoelastic proteins that facilitate mosquito movement are being investigated for use in tissue engineering and drug delivery applications. Even the non-wetting nanostructure of a mosquito eye has inspired the creation of a robust superhydrophobic surface coating that shows promise for biomaterial and drug delivery applications. Additionally, biosensors incorporating mosquito olfactory receptors have been built to detect disease-specific volatile organic compounds. Advanced technologies derived from mosquitoes, and insects in general, form a research area that is ripe for exploration and can uncover potential in further dissecting mosquito features for the continued development of novel medical innovations. [ABSTRACT FROM AUTHOR]

A soft gripper inspired by the glowing sucker octopus (Stauroteuthis syrtensis)' highly evolved grasping capability enabled by the umbrella‐shaped dorsal and ventral membrane between each arm is presented here, comprising of a 3D‐printed linkage mechanism used to actuate a modular mold silicone‐casting soft suction disc to deform. The soft gripper grasp can lift objects using the suction generated by the pump in the soft disc. Moreover, the protruded funnel‐shaped end of the deformed suctorial mouth can adapt to smooth and rough surfaces. Furthermore, when the gripper contacts the submerged target objects in a turbid environment, local suctorial mouth arrays on the suction disc are locked, causing the variable flow inside them, which can be detected as a tactile perception signal to the target objects instead of visual perception. Aided by the 3D‐printed linkage mechanism, the soft gripper can grasp objects of different shapes and dimensions, including flat objects, objects beyond the grasping range, irregular objects, scattered objects, and a moving turtle. The results report the soft gripper's versatility and demonstrate the vast application potentials of self‐adaptive grasping and sensing in various environments, including but are not limited to underwater, which is always a key challenge of grasping technology. [ABSTRACT FROM AUTHOR]

In this study, a bioinspired hierarchical structure was formed with superomniphobicity on a 7075 aluminium alloy using laser ablation. The morphology and wetting characteristics of the biomimetic sample surface were characterised using scanning electron microscopy, laser confocal microscopy, and contact angle measurements. The effect of the liquid properties and surface structures on the rolling behaviour was investigated. The results suggest that the fabricated biomimetic sample surface was a hierarchical structure. The prepared sample had superomniphobicity and low adhesion properties, and the contact angles of six different liquid droplets on the sample surface reached or approached 150°. Specifically, the largest contact angle was 152°, and the average rolling angle was 7.7°. This multi‐hydrophobic surface provides a valuable reference for the research study and use of a variety of solid–liquid contacts. [ABSTRACT FROM AUTHOR]

Although drag driven wind turbine is regarded as an efficient rotor for low wind speed regions, design reconfiguration is a continuous process in order to improve the performance of the rotor. The main governing factor that influences the performance of the rotor is the blade morphology. Hence, this paper presents a proposed nature-inspired design approach for the development of drag-driven wind turbine blade morphology. The design approach framework comprises three main elements, namely image processing, geometrical analysis and biohybridization. The proposed bio-hybridized design consists of a blade mainframe curve inspired by nautilus shell and barnacle on the blade surface. It is found that integration of barnacle geometries on the surface of the blade has affected the performance of the rotor. Result shows that the peak Cm is at λ = 0.55 for experimental and CFD is Cm = 0.238 and Cm = 0.253 respectively. The proposed design resulted in experimental and numerical Cp = 0.113 and Cp = 0.127 respectively at 7 m/s and λ = 0.7. The presented design technique with appropriate design bio-element provides a systematic method for engineers to model wind turbine blade morphologies. [ABSTRACT FROM AUTHOR]

Water splitting, as a promising clean energy source, has garnered significant attention owing to the escalating global energy crisis. However, prior research has largely focused on electrode materials rather than bubble manipulation, which plays a crucial role in the process. Although using the previously published "Releasing strategy" effectively eliminates micro-sized bubbles from the electrode material for efficient water splitting, the released tiny-sized bubbles pose challenges for controllable and pure collection. Herein, a new "Managing strategy", integrating the "Transporting strategy" for rapid directional bubble transport with the "Collecting strategy" for controllable bubble collection, aiming to develop smart integrated water-splitting devices for efficient continuous water splitting and pure gas collection. This advanced functional electrode, designed with a lotus leaf-inspired Janus wettability interface for timely directional bubble transport and a water-spider hair structure-inspired aerophilic surface for efficient bubble collection, enables pure, efficient, and continuous water splitting. It achieves this by releasing gas products of controllable larger sizes, collecting them at a faster rate, and reducing the probability of H 2 /O 2 collisions. Beyond enabling water splitting, this approach is also applicable to other gas-involving applications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)