Bioinspiration & Biomimetics最新文献

{"title":"Mechanisms of the impact of cross-sectional variations in the primary flight feather shaft on mechanical properties.","authors":"Huan Wang, Ming Ju, Yuliang Huang, Zhaohui Mu, Yulong Liang, Mingjin Xin, Liyan Wu","doi":"10.1088/1748-3190/ae4af2","DOIUrl":"10.1088/1748-3190/ae4af2","url":null,"abstract":"<p><p>Primary flight feather shafts, a critical structural component of avian flight, exhibit excellent mechanical properties. The cross-sectional and medullary foam internal cavity structures of the feather shaft exhibit a gradual variation along the shaft; however, the mechanism by which this gradual variation influences the mechanical properties of the shaft remains unclear. In this study, the structural characteristics of a primary flight feather shaft were analyzed. Subsequently, the effects of gradual variations in the cross-sectional shape and medullary foam internal cavity structure along the shaft on its buckling resistance, torsional stiffness, and bending behavior were investigated. The experimental results showed that, along the length of the primary flight feather shaft, its cross-sectional shape transitions progressively from circular to approximately pentagonal and finally to quadrilateral, while its medullary foam cavity structure gradually changes from a circular to an inverted triangular shape. Feather shafts with an approximately pentagonal cross-section and an elliptical medullary foam cavity structure exhibit excellent buckling resistance, torsional resistance, and bending stability. Finally, based on the structural characteristics of the feather shaft, bionic samples with different cross-sectional shapes and medullary foam cavity structures were fabricated using fused deposition modeling, and their bending properties were assessed through three-point bending tests. The experimental results demonstrated that the bioinspired prototype, featuring an approximately pentagonal cross-section and an elliptical medullary foam cavity structure exhibited optimal bending properties, achieving a maximum specific load-bearing capacity of 102.64 ± 1.70 N g^-1. This study provides bio-inspired insights into the design of lightweight structures.</p>","PeriodicalId":55377,"journal":{"name":"Bioinspiration & Biomimetics","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147312759","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Minimization of thrust and sideforce fluctuations of a two-segment ichthyoid propulsor for autonomous underwater vehicles.","authors":"Tomasz Szmidt","doi":"10.1088/1748-3190/ae54f0","DOIUrl":"10.1088/1748-3190/ae54f0","url":null,"abstract":"<p><p>This study deals with the problem of optimizing the geometry and motion of a two-segment articulated ichthyoid propulsor for autonomous underwater vehicles. The considered propulsor mimics the undulating body and caudal fin motion of a swimming fish; thus, the thrust and sideforce that are generated exhibit undesirable oscillations. The formulas for these hydrodynamic forces, which were derived in the author's previous work, are presented. For selected values of the mean thrust and the swimming speed, two problems of minimizing the thrust (1) and the sideforce (2) variance are solved by systematically searching the set of feasible solutions. Two considered objective functions lead to quite different results regarding the optimal geometry and motion of the propulsor. The propulsor minimizing the thrust variance should have the first segment shorter than the second one, and the propulsive fin should spread over almost the entire length of the second segment. When the objective is minimizing the sideforce variance, the first segment should be described by a length greater and the amplitude smaller than that of the second segment, and the propulsive fin should be small. For both objective functions, the optimal motion of the propulsor strongly depends on the swimming speed and generated thrust. Generating greater thrust at higher swimming speeds requires reducing the vibration period.</p>","PeriodicalId":55377,"journal":{"name":"Bioinspiration & Biomimetics","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147488466","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Morphing median fin enhances untethered tuna-inspired robotic fish's linear acceleration and turning maneuverability.","authors":"Wei Zheng, Hongbin Huang, Zhonglu Lin, Jinhu Zhang, Zhibin Liu, Han Wu, Boyu Zhang, Yu Zhang","doi":"10.1088/1748-3190/ae5a19","DOIUrl":"https://doi.org/10.1088/1748-3190/ae5a19","url":null,"abstract":"<p><p>Median fins in fish-like swimmers critically govern linear acceleration and maneuvering performance, yet their function remains underexplored in untethered robotic systems. To address this gap, we developed a free-swimming tuna-inspired robotic fish featuring a biomimetic morphing dorsal fin and conducted comprehensive hydrodynamic experiments. Our results demonstrate that dorsal fin erection significantly enhances maneuverability: it reduces head heave by 50%, increases linear acceleration by 27.94%, elevates turning angular velocity by 32.78%, and decreases turning radius by up to 24.89%. CFD simulations also preliminarily validated this mechanism, revealing enhanced vortex effects during median fin erected, along with stronger positive and negative pressure regions around the dorsal fin, which collectively suppress head heave and enhance the wake flow during acceleration. Conversely, the erected fin expands wetted surface area, reducing maximum cruising speed and efficiency during steady swimming. This trade-off mechanism explains why tuna erect median fins transiently during acceleration or turns but retract them post-maneuver to minimize drag. By pre-programming fin folding after acceleration, we confirmed its negligible impact on steady swimming efficiency. This study validates the functional role of morphing median fins in bio-inspired robotics and provides new insights into fin-mediated locomotor control in aquatic organisms.</p>","PeriodicalId":55377,"journal":{"name":"Bioinspiration & Biomimetics","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147596551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fire ant rafts offer principles and rules for synthetic programmable morphing matter.","authors":"Franck J Vernerey, Brian N Cox","doi":"10.1088/1748-3190/ae4ce3","DOIUrl":"10.1088/1748-3190/ae4ce3","url":null,"abstract":"<p><p>We examine fire-ant rafts as a model system of biological active matter composed of cohesive agents that interact through simple local rules to produce emergent collective dynamics. A hallmark of these rafts is treadmilling, a process enabled by the continuous cycling of ants through a multi-phase system, comprising in a minimal representation a solid-like network phase and a dilute motile phase that can migrate outside the network. Treadmilling requires the breaking of detailed balance in the fluxes between the phases, a signature of out-of-equilibrium systems. By combining experimental data with discrete agent-based simulations and a new continuum model, we show that simple rules governing the actions of single ants, based only on the positions, velocities and local forces an ant perceives and defining its next actions within a phase and triggering conditions for transition between phases, suffice to replicate the complex behavior of treadmilling and shape morphing of the raft as emergent phenomena. We also show that two principles hold empirically in the network phase: homeostasis of area density, a constraint that couples ant activity level to shape morphing in a very simple way; and the invariance of the network topology over relevant timescales, which supports global geometrical stability in the face of chaotic ant motions. Refined by evolution over very long times, the principles and rules governing fire ant rafts suggest design possibilities for achieving stable shape morphing in decentralized systems of synthetic programmable matter.</p>","PeriodicalId":55377,"journal":{"name":"Bioinspiration & Biomimetics","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147349738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The biodesign framework: professional biodesign practices.","authors":"Bert Vuylsteke, Louise Dumon, Jan Detand, Francesca Ostuzzi","doi":"10.1088/1748-3190/ae54ef","DOIUrl":"10.1088/1748-3190/ae54ef","url":null,"abstract":"<p><p>This study explores the professionalization of the rising design engineering discipline, called 'biodesign'. Despite its potential for circular, regenerative solutions, its industrial application remains limited. To address this challenge, this study investigates 'why' and 'how' professional designers engage in designing of, with and for biology. The study explores the motivations and practices of professional biodesign pioneers through extensive expert interviews (<i>n</i>= 21). A qualitative analysis applying the Qualitative Analysis Guide of Leuven methodology identified five key codes: biodesign mindset, -process, -resources, -materials, and -future. These aspects were further investigated through their five most cited sub-codes, offering evidence-based findings into current biodesign practice. Synthesising these findings, a novel methodological biodesign framework is proposed, that maps nested environments (operating space-biodesign space-biosphere space) and an iterative systemic cybernetical loop between human and more-than-human agencies. The framework offers a structured point of departure for biodesign professionalization and supports future empirical validation and tool development for professional practice and education.</p>","PeriodicalId":55377,"journal":{"name":"Bioinspiration & Biomimetics","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147488460","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deep dive into model-free reinforcement learning for underwater locomotion: theory and practice.","authors":"Yusheng Jiao, Feng Ling, Sina Heydari, Nicolas Heess, Josh Merel, Eva Kanso","doi":"10.1088/1748-3190/ae4930","DOIUrl":"10.1088/1748-3190/ae4930","url":null,"abstract":"<p><p>Aquatic animals and underwater robots operate in a complex physical world and must coordinate their bodies to achieve behavioral objectives such as navigation and predation. With recent developments in deep reinforcement learning (RL), it is now possible for scientists and engineers to synthesize sensorimotor strategies (policies) for specific tasks using physically simulated bodies and environments. However, beyond solving individual control problems, these methods offer an exciting framework for understanding the organization of an animal sensorimotor system in connection with its morphology and physical interaction with the environment, as well as for deriving general design rules for bioinspired underwater robots. Although algorithms and code implementing both learning agents and environments are increasingly available, the basic assumptions and modeling choices that go into the formulation of an embodied feedback control problem using deep RL may not be immediately apparent. In this tutorial, we provide a self-contained introduction to model-free RL for embodied agents in underwater environments, with a focus on<i>actor-critic</i>methods. We first present the mathematical formulation of RL, highlighting where physical modeling choices enter. We then discuss the practical aspects of implementing actor-critic algorithms. Drawing on recent examples of RL-controlled swimmers, we provide guidelines for choosing observations, actions, and rewards consistent with biological behavior, and we outline how RL can be used as a tool to explore hypotheses about the feedback control underlying animal and robotic behavior.</p>","PeriodicalId":55377,"journal":{"name":"Bioinspiration & Biomimetics","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147277657","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"How fish body stiffness distribution affects swimming performance: a theoretical perspective.","authors":"Xiaobo Zhang, Zhongcai Pei, Zhiyong Tang","doi":"10.1088/1748-3190/ae4d94","DOIUrl":"10.1088/1748-3190/ae4d94","url":null,"abstract":"<p><p>Stiffness exerts a significant influence on swimming locomotion of fish. Biological experiments have demonstrated that the stiffness of different body segments in fish is inherently heterogeneous. Although the stiffness variation patterns from head to tail exhibit certain interspecific differences among various fish species, they generally follow a decreasing trend from anterior to posterior. In this study, based on the resistive drag model, we discretized the original model and incorporated improvements such as the distribution function of active bending moments. The analytical model developed herein integrates the stiffness distribution of the fish body into the analysis of its locomotion. Through this model, several typical stiffness distribution patterns were investigated, with a particular focus on sub-topics such as various decreasing distributions and the effects of different segment quantities. The results indicate that a rapidly decreasing stiffness distribution with a low ratio of minimum-to-maximum stiffness yields the optimal swimming performance. This work serves not as a substitute for but rather a supplement to pertinent biological experiments. Simultaneously, it constitutes a foundational study for variable-stiffness distribution robotic fish, informing and guiding future design endeavors.</p>","PeriodicalId":55377,"journal":{"name":"Bioinspiration & Biomimetics","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147357433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Investigating woodpecker drumming using the center of percussion.","authors":"Eva M Koczur, Bethany M Parkinson, Mary I Frecker, Taylor E Greenwood","doi":"10.1088/1748-3190/ae4f47","DOIUrl":"10.1088/1748-3190/ae4f47","url":null,"abstract":"<p><p>Woodpeckers are known for their distinctive drumming behavior used to forage for food and attract mates. During drumming, woodpeckers endure decelerations up to 1200 g without developing apparent brain injuries. Because of this extraordinary capability, woodpecker anatomy has served as an inspiration for structures that reduce forces during impacts, with potential applications in helmet design and vehicle safety. Previous studies theorized that impact energy from drumming is primarily absorbed by anatomical features in the woodpecker's head such as the tongue, hyoid bone, spongy bone, or lower beak. However, this explanation was challenged by a recent study reporting that shock-absorbing anatomy in the head would decrease drumming efficiency to an unrealistic threshold. In light of these conflicting theories, the exact methods used by woodpeckers to mitigate the adverse effects of drumming remain unclear. This work investigates the dynamics of woodpecker drumming using a principle called the center of percussion, which relates the location of an applied force (called the center of percussion, CoP) to a corresponding location of zero reaction force (called the center of rotation, CoR). We hypothesized that woodpecker anatomy exploits the relationship between the CoP and CoR to reduce reaction forces at critical anatomical locations, mitigating the adverse effects of drumming. We apply this hypothesis to woodpeckers by using two simplified rigid body models of the woodpecker's anatomy and performing parameter sweeps to investigate the location of zero reaction force when the applied force is at the woodpecker's beak. Results indicate zero reaction force in the lower body near the joint connecting the woodpecker's femur for a body-head model and zero reaction force near a joint in the lower neck for a neck-head model. The absence of reaction forces at these locations may provide critical insight into woodpecker dynamics and future investigation into strategies for reducing impact forces.</p>","PeriodicalId":55377,"journal":{"name":"Bioinspiration & Biomimetics","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-03-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147391765","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vortex dynamics from burst-and-coast motion of anguilliform and carangiform swimmers.","authors":"Zahra Maleksabet, Maham Kamran, Ali Tarokh, Muhammad Saif Ullah Khalid","doi":"10.1088/1748-3190/ae4f48","DOIUrl":"10.1088/1748-3190/ae4f48","url":null,"abstract":"<p><p>Fish perform various propulsive maneuvers while swimming by generating traveling waves along their bodies and producing thrust through tail strokes. Anguilliform swimmers spread motion along the body, while carangiform swimmers' motion is more prominent near their tails. Many species also switch between continuous undulation and intermittent swimming, such as burst-and-coast maneuver, which can save energy but can also change the wake structure and hydrodynamic forces. Our current study aims at explaining how duty cycle (DC), undulatory gaits, and Strouhal number (St), shape the near-body vortices, overall wakes, and the hydrodynamic forces. We carry out three-dimensional simulations at<i>Re</i> = 3000 for flows around tethered models of an eel (anguilliform) and a Jack Fish (carangiform) forDC=0.2-1.0andSt=0.30and 0.40 with a constant incoming flow velocity. Our results reveal that the burst-and-coast motion for both swimmer produce bow-shaped wakes, the two rows of which on the sides approach each other to form a more coherent wake asDCis increased to 1.0 that corresponds to the wake of continuously undulating swimmers. It is also found that the intermittent motion at a higher Strouhal number produces more drag, contrary to the continuous undulatory kinematics. We further investigate this behavior by quantifying the strengths of vortices produced around the two swimmers and their instantaneous kinematic metrics. A detailed analysis for the role of different body sections in the production of unsteady streamwise forces is also presented. These insights provide important connections between the swimmers' physiologies, their kinematics, and the governing vortex dynamics to attain certain hydrodynamic metrics for designing next-generation autonomous bio-inspired underwater robots.</p>","PeriodicalId":55377,"journal":{"name":"Bioinspiration & Biomimetics","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147391824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bioinspired additive manufacturing material optimization for increased stiffness and improved strain sensing in robotic limbs.","authors":"Gesa F Dinges, Isabella M Kudyba, Foster O Holmquist, Sasha N Zill, Nicholas S Szczecinski","doi":"10.1088/1748-3190/ae4af1","DOIUrl":"10.1088/1748-3190/ae4af1","url":null,"abstract":"<p><p>Robots traversing uneven terrain may require precise calculation of limb kinematics (e.g. foot position from joint angles and segment dimensions) and sensing of force for adaptive walking control. To facilitate these calculations, robots often have very rigid limb segments with a stiff load cell between the limb and end effector (e.g. foot). Insects also must compute kinematics and measure force when walking, but sense forces quite differently, using strain sensors embedded in their exoskeletons distributed across their legs to infer force. Due to this configuration, more rigid leg segments would simplify the computation of kinematics (e.g. foot position), but would reduce the strain that could be measured to infer force, creating a trade-off between structural stiffness and force sensitivity. Insects appear to balance leg segment rigidity and force measurement sensitivity through heterogeneous cuticle that creates stress (and thus strain) concentrations near strain sensing organs but keeps the segment rigid overall. To engineer robot limbs that balance rigidity and force sensitivity, we leveraged these biological principles and additive manufacturing to explore the effect of localized Kevlar® fiber reinforcement on the stiffness and strain sensing performance of 3D printed robotic limbs. We fabricated limbs with no, partial, and full Kevlar® fiber reinforcement and evaluated their performance through beam bending, robot stepping, and fatigue tests. The limbs were assessed for endpoint stiffness, strain sensitivity, and structural integrity under repeated loading. Results reveal that partial fiber reinforcement offers the most effective compromise, increasing endpoint stiffness to facilitate kinematics calculations while amplifying strain signals for high signal-to-noise ratios. Furthermore, partially reinforced limbs demonstrated superior fatigue resistance, retaining sensing capability after prolonged cyclic loading. These findings suggest that localized, heterogeneous reinforcement that mimics the structural and sensory trade-offs found in insect exoskeletons can enhance both the mechanical and sensing performance of robotic limbs.</p>","PeriodicalId":55377,"journal":{"name":"Bioinspiration & Biomimetics","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2026-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147312777","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"计算机科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}