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(a-c) Images of Polyommatus icarus (common blue) butterfly wings at different magnifications, showing that they are composed of thousands of scales with complex hierarchical structures (courtesy of W. Barthlott).
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Nature has developed materials, objects and processes that function from the macroscale to the nanoscale. These have gone through evolution over 3.8 Gyr. The emerging field of biomimetics allows one to mimic biology or nature to develop nanomaterials, nanodevices and processes. Properties of biological materials and surfaces result from a complex i...
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Friction is a dissipative irreversible process; therefore, entropy is produced during frictional contact. The rate of entropy production can serve as a measure of degradation (e.g. wear). However, in many cases friction leads to self-organization at the surface. This is because the excess entropy is either driven away from the surface, or it is rel...
With unique hierarchical fibrillar structures on their feet, gecko lizards can walk on vertical walls or even ceilings. Recent experiments have shown that strong binding along the shear direction and easy lifting in the normal direction can be achieved by forming unidirectional carbon nanotube array with laterally distributed tips similar to gecko'...
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... Biomimetics deals with forming models inspired by nature to solve complex problems or satisfy human needs. In biomimetics, for example, the lotus leaf inspires the surface textures to enhance properties such as hydrophobicity, selfcleaning and drag reduction in fluid flow (Bhushan, 2009), and the aquatic drag is reduced with the help of surface micro-textures on the shark skin (Dean and Bhushan, 2010). In the same way, many researchers implemented biomimetic textures on the contact surfaces of mechanical components. ...
Purpose-This paper aims to investigate the tribological benefits of a biomimetic teardrop surface texture inspired by snakeskin compared to conventional surface textures with the help of geometrical and flow parameters using computational fluid dynamics techniques. Design/methodology/approach-The lubricant is assumed to be Newtonian, and the flow is laminar with constant viscosity and isothermal property. The governing equations, continuity and Navier-Stokes equation, are discretised by the finite volume method, and cavitation modelling is included. The discretisation for the momentum equations is carried out using the second-order difference method for the SIMPLEC algorithm of pressure-velocity coupling. Findings-The results indicate that biomimetic teardrop surface texturing performs better than conventional shapes surface textures in improving tribological performance. Furthermore, the parallel texture orientation along with the flow generates a high-pressure distribution relative to other orientations. Surface texture area density also highly influences the load-carrying capacity, which is optimum at 29%. Zigzag pattern arrangement performs better compared to linear pattern arrangement of texturing. Originality/value-The paper proposes that this unique biomimetic teardrop shape can give better tribological performance than conventional shapes. Peer review-The peer review history for this article is available at: https://publons.com/
... The fouling-resistant performance of shark skin has been attributed to the mechanisms resulting in its capacity to reduce skin friction drag. More specifically, it is believed that the hydrodynamic effects of drag reduction allows for a rapidly moving water layer located near the structured surface that carries away particles that would otherwise settle and adhere to the surface [17,18]. Furthermore, if nature employs a fundamental relationship between fouling resistance and drag reduction, it can be anticipated that the fouling-resistant topography of the Dosinia juvenilis also possesses an ability to reduce the drag associated with the turbulent coastal waters of the species' natural environment [16]. ...
Many species of plants and animals show an ability to resist fouling with surface topographies tailored to their environments. The mollusk species Dosinia juvenilis has demonstrated the ability to resist the accumulation of fouling on its outer surface. Understanding the functional mechanism employed by nature represents a significant opportunity for the persistent challenges of many industrial and consumer applications. Using a biomimetic approach, this study investigates the underlying hydrodynamic mechanisms of fouling resistance through Large Eddy simulations of a turbulent boundary layer above a novel ribletted surface topography bio-inspired by the Dosinia juvenilis. The results indicate a maximum drag reduction of 6.8% relative to a flat surface. The flow statistics near the surface are analogous to those observed for other ribletted surfaces in that the appropriately sized riblets effectively reduce the spanwise and wall-normal velocity fluctuations near the surface. This study supports the understanding that nature employs ribletted surfaces toward multiple functionalities including the considered drag reduction and fouling resistance.
... Biomimicry in design is a field that draws inspiration from nature to create sustainable and innovative solutions to various challenges [30]. The underlying concept of this method is that the natural world has created proficient and productive systems through millions of years of evolution, and that these systems can offer useful perspectives on addressing issues in engineering, architecture, and other domains [31][32][33]. ...
Esophageal cancer is a complex and challenging tumor to treat, with esophageal stenting being used as a palliative measure to improve the quality of life of patients. Self-expandable metal stents (SEMS), self-expandable plastic stents (SEPS), and biodegradable stents are the most commonly used types of stents. However, complications can arise, such as migration, bleeding, and perforation. To address issues of migration, this study developed a novel 3D printed bioinspired esophageal stent utilizing a highly flexible and ductile TPU material. The stent was designed to be self-expanding and tubular with flared ends to provide secure anchorage at both the proximal and distal ends of the structure. Suction cups were strategically placed around the shaft of the stent to prevent migration. The stent was evaluated through compression–recovery, self-expansion, and anti-migration tests to evaluate its recovery properties, self-expansion ability, and anchoring ability, respectively. The results indicated that the novel stent was able to recover its shape, expand, keep the esophagus open, and resist migration, demonstrating its potential for further research and clinical applications. Finite element analysis (FEA) was leveraged to analyze the stent’s mechanical behavior, providing insights into its structural integrity, self-expansion capability, and resistance against migration. These results, supported by FEA, highlight the potential of this innovative stent for further research and its eventual application in preclinical settings.
... In nature, a variety of surfaces, such as butterfly wings, moth eyes, insect legs, and lotus leaves, display the superhydrophobic property with a self-cleaning function [4]. This is because the highly resisted water droplet picks up the dust particles when it rolls off the surface. ...
In this study, hydrophilic cellulosic wood (Tectona grandis) is modified into superhydrophobic wood with the aid of octadecyltrichlorosilane (OTS) and silica nanoparticles (SiO2) using one-step facile method. The prepared superhydrophobic wood possessed water contact angle (WCA) of 167 ± 2° and the sliding angle was less than 4°. The surface morphology was examined by scanning electron microscopy (SEM) and it showed agglomeration of nanostructures on the surface of superhydrophobic wood. Fourier transform infrared spectroscopy was used to analyse the functional groups present on the produced wood, and the results showed the existence of –\({{\text{CH}}}_{2}\) and –\({{\text{CH}}}_{3}\) groups. The exceptional self-cleaning and stain resistance of modified wood made it suitable for a variety of applications. Also, it is mechanically durable as it underwent and sustained tape peeling, sand abrasion and water jet impact. The modified wood demonstrated excellent durability in exposure to UV and on exposure to solutions of varying pH. This makes the fabricated wood suitable for various applications.
... Organisms evolve to survive in harsh natural environments and have morphologies and internal tissue structures with the necessary characteristics in the necessary places. The study of these characteristics is expected to be useful in the development of novel high-performance materials that exceed the current state [1][2][3][4][5][6][7][8][9][10][11][12][13]. ...
The coconut crab, Birgus latro, has black protrusions on the tops of its walking legs and claw fingers. In addition, there are regularly aligned small black protrusions on parts of the exoskeleton surface of the claws and leg. In this study, the elemental composition, crystal structure, tissue structure, and mechanical properties of these protrusions were studied using a materials science approach, and the results were compared with those of mineralized cuticle. These leg tips were found to be a non-calcified fibrous tissue of α-chitin connected to the mineralized cuticle. The tip of the second walking leg was elongated and had a pointed shape with an oval cavity at its center that was more than 1000 times larger than the pore tubes (100–350 nm) of the mineralized cuticle. It was very soft, with a hardness of 0.4 GPa, corresponding to 11–12% of the hardness of the hard exocuticle and 55–57% of the hardness of the soft endocuticle. The elastic modulus of 8.0 GPa obtained by means of nanoindentation testing was consistent with that of α-chitin fibers of shrimp shells obtained by means of tensile testing. These soft protrusions provide a secure grip on the surfaces of trees or rocks and protect the claw fingertips. It was concluded that the black protrusions are related to a unique ecological (engaging in vertical movements, entering and exiting limestone caves, and escape behavior) aspect of the coconut crab, the largest terrestrial crustacean.
... Biomimicry is a third conceptual figure that captures the technology-nature interface, yet quite differently from cyborgs and technonatures. Defined as taking inspiration from nature towards advancing solutions to human problems, biomimicry is particularly popular within the fields of product design, architecture, urban design, engineering and materials science (Passino, 2005;Bhushan, 2009;Reed, Klumb et al., 2009;Zari, 2018;Pawlyn, 2019;Taylor Buck & While, 2021). Whilst emulating nature in human designs is perhaps as old as humans themselves, the contemporary iterations of the concept were developed and popularised by biophysicist Otto Schmitt (1963, on the idea of biomimetics) and biologist Janine Benyus (1997). ...
Digital tools and practices are transforming societal relationships with non-human worlds—whether through smartphone apps that city dwellers use to navigate urban forests, robotic bees that pollinate crops, or webcams that livestream rare birds' nests. Recent academic and popular interest in the coming together of digital and natural worlds has generated both creative and critical reflections on what the digital means for the very concept of nature, troubling the latter's ontological stability. In this Introduction to the special issue Digital Natures: Reconfiguring Ontologies, Epistemologies, and Politics we claim that the digital, when considered beyond an epistemological register, is a productive and political force that is unsettling, rather than reinforcing, the boundaries between society and nature. We review the extensive body of work from across geography and the social sciences that is actively engaging with digital–nature intersections, and historicise current debates through reference to the figures of the cyborg, technonatures, biomimicry and digital organisms. Asking whether digitalized practices of sensing, abstraction and algorithmic recombination simply mirror a pre-existing and external Nature, or whether they advance a reconceptualization of nature, we set out to trace the progressive political potential of a digitally-entangled ontological redefinition of nature. We discuss how, within emerging digital natures, agencies are entangled in a reimagining of what both nature and society are about. Here, we argue, lies the transformative potential of digital natures—precisely in challenging and subverting the ontological place of an external Nature. The introduction finishes by simultaneously outlining a research agenda for digital natures and presenting the six papers that comprise the special issue.
... Nature has long been a wellspring of inspiration for scientific innovation, offering intricate designs and dynamic processes that have fuelled advances across various domains [1,2]. It can demonstrate some of the best examples of both iontronics [3] -exemplified by the propagation of the action potential [4] -and nanofluidics, by presenting us with the complex machinery that are ion channels and many other biological pores, capable of a highly specialized modulation of the signaling and transport of ions, water and biological molecules across the cell membranes [5,6]. ...
Reliable and controllable switches are crucial in nanofluidics and iontronics. Ion channels found in nature serve as a rich source of inspiration due to their intricate mechanisms modulated by stimuli like pressure, temperature, chemical species, and voltage. The artificial replication of the properties of these channels is challenging due to their complex chemistry, limited stability range, and intricate moving parts, allosterically modulated. Nonetheless, we can harness some of the gating mechanisms of ion channels for nanofluidic and iontronic purposes. This theoretical and computational study explores the use of electrowetting in simple hydrophobic nanopores to control their conductance using an external applied voltage. We employ restrained molecular dynamics to calculate the free energy required for wetting a model nanopore under different voltages. Utilizing a simple theory, we generate free energy profiles across a wide voltage range. We also computed transition rates between conductive and non-conductive states, showing their voltage dependence and how this behavior can impair memory to the system, resembling the memristor behavior voltage-gated channels in the brain. The proposed framework provides a promising avenue for designing and controlling hydrophobic nanopores via electrowetting, enabling potential applications in neuromorphic iontronics.
... The study of soil dynamics began in the 1920s, with Soviet scholars systematically studying the plowing process of soil using mathematical methods. Nichols ML in the United States studied the operation of burial machinery, but almost all research results are based on physical experiments [13][14][15][16][17]. ...
This paper aims to explore the current state of research on submarine cable burial machines and proposes a novel mechanical burial machine design employing a chain-type structure based on a combination of theoretical considerations and practical requirements. Through theoretical analysis, simulation, and experimental studies, the cutting process of the mechanical burial machine is investigated in detail, with special attention given to the seabed conditions in the Northeast Asia region. Starting from the dynamic process of the blade–soil interaction and the working mechanism of the blade–soil system, an accurate and reliable model for the seabed rock–soil stress is established, along with a fast computation method. A destructive analysis of rock–soil mechanical cutting is performed, elucidating the influences of the cutting depth, cutting angle, and chain blade cutting speed on cutting resistance. This paper provides reference parameters for the design of chain-type trenching devices under different seabed conditions, and adjustments are made based on simulation experiments and actual soil trenching test results. These analyses contribute practical and reliable guidance for the design and optimization of submarine cable burial machines.
... The basic idea of biomimetics is that nature has been conducting research and development for billions of years, leading to the evolution of highly efficient and optimized solutions to various problems. By studying and understanding these natural designs and strategies, scientists, engineers, and researchers can draw inspiration to design better technologies, materials, and systems [3]. ...
... In the technical field, biomimetics has found numerous applications and opportunities. Drawing inspiration from nature's design principles, structures, and systems, biomimetics has led to innovative solutions in various technological domains, as [1,3,4]: ...
... Designing wings based on the principles of bird flight, such as the wing shape and feather orientation, has led to improved lift and reduced drag. Additionally, the study of bird flocking behavior has inspired algorithms for optimizing air traffic management [3]. Materials Science: Biomimetics has inspired the development of advanced materials with exceptional properties. ...
... In recent years, enormous progress can be seen in 3D fabrication methods of bioinspired devices, including advances in direct 3D manufacture (e.g., 3D printing, laser ablation and templating) and 2D-to-3D assembly (e.g., soft active materials-based actuation methods and mechanically guided 3D assembly) [2,[28][29][30][31]. Additionally, 3D bioinspired flexible devices (e.g., sensors, on bioinspired design strategies, including bioinspired heterogeneous materials and actuators [23,29,32], while comprehensive reviews on bioinspired designs of 3D flexible devices and functional systems are still lacking. ...
... presents some typical surface morphologies of biological organisms, such as the trichomes on the salvinia leaf, the placoid scales on the shark skin, the mastoids on the lotus leaf, the setae on the gecko toe and the nano-nipples on the mosquito eye[32]. These multi-scale, hierarchical surface morphologies are particularly crucial to hydrophobicity, hydrophilicity, reversible adhesion, drag reduction, energy conversion, light coloration, and many other biological functions, providing valuable inspirations for the design of 3D flexible sensors, optoelectronics and energy harvesters. ...
Flexible devices and functional systems with elaborated three-dimensional (3D) architectures can endow better mechanical/electrical performances, more design freedom, and unique functionalities, when compared to their two-dimensional (2D) counterparts. Such 3D flexible devices/systems are rapidly evolving in three primary directions, including the miniaturization, the increasingly merged physical/artificial intelligence and the enhanced adaptability and capabilities of heterogeneous integration. Intractable challenges exist in this emerging research area, such as relatively poor controllability in the locomotion of soft robotic systems, mismatch of bioelectronic interfaces, and signal coupling in multi-parameter sensing. By virtue of long-time-optimized materials, structures and processes, natural organisms provide rich sources of inspiration to address these challenges, enabling the design and manufacture of many bioinspired 3D flexible devices/systems. In this Review, we focus on bioinspired 3D flexible devices and functional systems, and summarize their representative design concepts, manufacture methods, principles of structure-function relationship and broad-ranging applications. Discussions on existing challenges, potential solutions and future opportunities are also provided to usher further research efforts toward realizing bioinspired 3D flexible devices/systems with precisely programmed shapes, enhanced mechanical/electrical performances, and high-level physical/artificial intelligence.
