Wall-climbing robots can stably ascend vertical walls and even ceilings,making them suitable for specialized tasks in high-risk,confined,and harsh conditions.Therefore,they have excellent application prospects and sub...Wall-climbing robots can stably ascend vertical walls and even ceilings,making them suitable for specialized tasks in high-risk,confined,and harsh conditions.Therefore,they have excellent application prospects and substantial market demand.However,several challenges remain,including limited load-carrying capacity,short operational duration,a high risk of detachment,and the lack of standardized physical and control interfaces for carrying auxiliary equipment to complete missions.This study analyzes the macro and micro structures and movement mechanisms of typical organisms in terms of negative pressure adsorption,hook-and-claw adhesion,dry adhesion,and wet adhesion.The exploration of biological wall-climbing mechanisms is integrated with the adhesion techniques used in practical wall-climbing robots.Additionally,the mechanisms,properties,and typical wall-climbing robots associated with adhesion technologies were investigated,including negative pressure adsorption,hook-and-claw adhesion,bionic dry adhesion,bionic wet adhesion,electrostatic adhesion,and magnetic adhesion.Furthermore,the typical gaits of quadruped and hexapod robots are analyzed,and bionic control techniques such as central pattern generators,neural networks,and compliant control are applied.Finally,the future development trends of wall-climbing robots will be examined from multiple perspectives,including the diversification of bionic mechanisms,the advancement of mechanical structure intelligence,and the implementation of intelligent adaptive control.Moreover,this paper establishes a solid foundation for the innovative design of bionic wall-climbing robots and provides valuable guidance for future advancements.展开更多
Based on research into bionic butterflies for environmental detection and ecological management,a scheme was proposed to develop and manufacture a bionic aircraft with two wings inspired by specific butterfly species....Based on research into bionic butterflies for environmental detection and ecological management,a scheme was proposed to develop and manufacture a bionic aircraft with two wings inspired by specific butterfly species.A flapping-wing aircraft with a simple structure was designed,and its two-wing design was optimized.The research focused on several key areas:the design and optimization of the wings,the development of the transmission mechanism,hardware design and fabrication,and 3D printing for component manufacturing.This resulted in the bionic replication of the wing shape and structure of the Tiger Papilio butterfly.The final bionic butterfly features a wingspan of 29.5 cm and a total weight of 13.8 g.This project integrates mechatronic principles and provides a valuable reference for advancements in the field of bionic butterflies.Future research could explore the aerodynamic characteristics of wings and innovative design approaches in greater depth.展开更多
Galloping cheetahs,climbing mountain goats,and load hauling horses all show desirable locomotion capability,which motivates the development of quadruped robots.Among various quadruped robots,hydraulically driven quadr...Galloping cheetahs,climbing mountain goats,and load hauling horses all show desirable locomotion capability,which motivates the development of quadruped robots.Among various quadruped robots,hydraulically driven quadruped robots show great potential in unstructured environments due to their discrete landing positions and large payloads.As the most critical movement unit of a quadruped robot,the limb leg unit(LLU)directly affects movement speed and reliability,and requires a compact and lightweight design.Inspired by the dexterous skeleton–muscle systems of cheetahs and humans,this paper proposes a highly integrated bionic actuator system for a better dynamic performance of an LLU.We propose that a cylinder barrel with multiple element interfaces and internal smooth channels is realized using metal additive manufacturing,and hybrid lattice structures are introduced into the lightweight design of the piston rod.In addition,additive manufacturing and topology optimization are incorporated to reduce the redundant material of the structural parts of the LLU.The mechanical properties of the actuator system are verified by numerical simulation and experiments,and the power density of the actuators is far greater than that of cheetah muscle.The mass of the optimized LLU is reduced by 24.5%,and the optimized LLU shows better response time performance when given a step signal,and presents a good trajectory tracking ability with the increase in motion frequency.展开更多
The robotic airship is one of the most unique and promising green aircraft,however,as a“lighter-than-air aircraft”and“thermal aircraft”,its long-endurance flight has great difficulties in decreasing drag and contr...The robotic airship is one of the most unique and promising green aircraft,however,as a“lighter-than-air aircraft”and“thermal aircraft”,its long-endurance flight has great difficulties in decreasing drag and controlling buoyancy and pressure under thermal effects.In this work,we reported a robotic airship inspired by the Physalia physalis,imitating its morphology,physiological structure,and biological behaviors.The hull is designed by imitating the morphology of the Physalia physalis,and the gasbags including a helium balloon,two ballonets,and a thermoregulation gasbag are designed by imitating the physiological structure and biological behaviors of the pneumatophore,bladder,and gland of the Physalia physalis,respectively.Experimental results show that the bionic airship has an increase of about 40%in lift-to-drag and decreases the pressure in helium balloon by 47.5%under thermal effects,and has better aerodynamic performances and thermoregulation performances than conventional airships.展开更多
In engineering,the demand for high energy absorption by structures subjected to impact loads is increasing.Balancing the limited space,manufacturing feasibility,and energy absorption capabilities is a key point in the...In engineering,the demand for high energy absorption by structures subjected to impact loads is increasing.Balancing the limited space,manufacturing feasibility,and energy absorption capabilities is a key point in the design of many enclosed structures with energy absorption requirements.To achieve a lightweight design and controllable energy absorption by the structures,within a limited space,this study proposes a bio-inspired double-layer impact-resistant structure that can be manufactured by an additive manufacturing method(powder bed fusion),inspired by the microstructure of a woodpecker’s head.The structure is composed of two basic structural units:a quasi-circular ring and an oblique cylinder.The controllable energy absorption capabilities of the structure were studied through a combination of theoretical analyses,numerical simulations,and physical experiments.The results showed that,for the quasi-circular ring structure,the specific energy absorption range of 13-72 J/g could be effectively regulated by adjusting the structural parameters.The specific energy absorption range of 11-137 J/g could be effectively regulated for oblique cylindrical structures.Finally,the structure was applied to the design of engineering impact-resistant devices,proving the effectiveness of the controllable energy absorption of the structure.Moreover,the design process of the structure was optimized,laying a foundation for the structure to better serve engineering design applications.展开更多
Inspired by natural biomimetic structures exemplified by femoral bones,the shell-infill composite design has emerged as a research focus in structural optimization.However,existing studies predominantly focus on unifo...Inspired by natural biomimetic structures exemplified by femoral bones,the shell-infill composite design has emerged as a research focus in structural optimization.However,existing studies predominantly focus on uniform-thickness shell designs and lack robust methodologies for generating high-resolution porous infill configurations.To address these challenges,a novel topology optimization framework for full-scale shell-filled composite structures is developed in this paper.First,a physics-driven,non-uniform partial differential equation(PDE)filter is developed,enabling precise control of variable-thickness shells by establishing explicit mapping relationships between shell thickness and filter radii.Second,this study addresses the convergence inefficiency of traditional full-scale topology optimization methods based on local volume constraints.It is revealed that a reduced influence radius exacerbates algorithm convergence challenges,thereby impeding the design of intricate porous structures.To overcome this bottleneck,a physics-driven stress skeleton generation method is developed.By integrating stress trajectories and rasterization processing,this method constructs an initial density field,effectively guiding material evolution and significantly enhancing convergence in porous structural optimization within the full-scale framework.Classical numerical examples demonstrate that our proposed optimization framework achieves biomimetic non-uniform shell thickness optimization and enables precise control of the shell thickness.Additionally,density preprocessing effectively eliminates intermediate density regions and void aggregation.Moreover,the generated trabecular-like infill patterns with spatially graded porosity,akin to multiscale topology optimization(MTO),provide an innovative solution for multifunctional,lightweight,complex shell-infill composite structures in aerospace and biomedical applications.展开更多
The wrist unit is crucial in humanoid robots,determining their operational dexterity and precision.To address current challenges such as excessive size,limited Degrees of Freedom(DoFs),and insufficient load capacity,w...The wrist unit is crucial in humanoid robots,determining their operational dexterity and precision.To address current challenges such as excessive size,limited Degrees of Freedom(DoFs),and insufficient load capacity,we propose a 3-DoF humanoid wrist inspired by the human forearm and wrist anatomy.This paper explores the principles of wrist bionic design and introduces a parallel mechanism actuated by a brushless DC motor(BLDC)-ball screw to achieve flexion/extension(F/E)and radial flexion/ulnar deviation(R/U),as along with pronation/supination(P/S)through an end-coupling design.We conducted an analysis on the inverse kinematic model and singularities of the humanoid wrist.Additionally,the workspace and motion capabilities of the humanoid wrist were evaluated.A prototype based on this design was built to demonstrate its motion and functional performance,verifying the feasibility and practicality of the humanoid wrist.This research provides a more compact design approach for future humanoid wrist development.展开更多
High load-bearing efficiency is one of the advantages of biological structures after the evolution of billions of years. Biomimicking from nature may offer the potential for lightweight design. In the viewpoint ofrnec...High load-bearing efficiency is one of the advantages of biological structures after the evolution of billions of years. Biomimicking from nature may offer the potential for lightweight design. In the viewpoint ofrnechanics properties, the culm of bamboo comprises of two types of cells and the number of the vascular bundles takes a gradient of distribution. A three-point bending test was carried out to measure the elastic modulus. Results show that the elastic modulus of bamboo decreases gradually from the periphery towards the centre. Based on the structural characteristics of bamboo, a bionic cylindrical structure was designed to mimic the gradient distribution of vascular bundles and parenchyma cells. The buckling resistance of the bionic structure was compared with that of a traditional shell of equal mass under axial pressure by finite element simulations. Results show that the load-bearing capacity of bionic shell is increased by 124.8%. The buckling mode of bionic structure is global buckling while that of the conventional shell is local buckling.展开更多
Each specific structure of organisms is the best choice under specific circumstances.The excellent characteristic structures of these organisms have great application potential in the design and multi-functional optim...Each specific structure of organisms is the best choice under specific circumstances.The excellent characteristic structures of these organisms have great application potential in the design and multi-functional optimization of energy-absorbing structures such as vehicle collisions,satellite landings,and military equipment.In this paper,using the principle of structural bionics,using the advantages of the honeycomb structure and the light weight and high strength of beetle elytra,four bionic lattice structures are studied:CH,ZPRH,SCH and IBE.Using NiTi shape memory alloy,a unique material as the base material,samples are prepared using selective laser melting(SLM)technology.By comparing the test results of the quasi-static compression test with the results of the numerical simulation,it is found that compared with the other three bionic lattice structures,the SCH structure has the best energy absorption effect in the effective stroke in the test,and the specific energy absorption can reach 6.32 J/g.ZPRH,SCH,and IBE structures not only have good and stable deformation behavior,but also have excellent impact resistance and shape memory properties.The design of these structures provides a reference for the design of anti-shock cushioning structures with self-recovery functions in the future.展开更多
The mechanisms of soil structure interaction have drawn much attention in the past years in the installation and operation of jack-up platform. A bionic spudcan produced by biomimetic of egg and snail shell is propose...The mechanisms of soil structure interaction have drawn much attention in the past years in the installation and operation of jack-up platform. A bionic spudcan produced by biomimetic of egg and snail shell is proposed, and the performance of the penetration and extraction are analyzed by numerical method. The geometric contour of egg and snail shell is measured, and its mathematical model is established respectively. According to the structure of existing spudcan of jack-up platform, three kinds of typical biomimetic spudcan are designed. Furthermore, numerical analysis models of biomimetic spudcan are established respectively to study the soil structure interaction mechanism in the process of penetration and extraction, and contrastive analysis of resistance characteristics are carried out. To conclude, the results show that the biomimetic spudcan facilitates the platform installation, and it is also beneficial to the improvement of the bearing capacity of spudcan.展开更多
A variety of prosthetic ankles have been successfully developed to reproduce the locomotor ability for lower limb amputees in daily lives. However, they have not been shown to sufficiently improve the natural gait mec...A variety of prosthetic ankles have been successfully developed to reproduce the locomotor ability for lower limb amputees in daily lives. However, they have not been shown to sufficiently improve the natural gait mechanics commonly observed in comparison to the able-bodied, perhaps due to over-simplified designs of functional musculoskeletal structures in prostheses. In this study, a flexible bionic ankle prosthesis with joints covered by soft material inclusions is developed on the basis of the human musculoskeletal system. First, the healthy side ankle–foot bones of a below-knee amputee were reconstructed by CT imaging. Three types of polyurethane rubber material configurations were then designed to mimic the soft tissues around the human ankle, providing stability and flexibility. Finite element simulations were conducted to determine the proper design of the rubber materials, evaluate the ankle stiffness under different external conditions, and calculate the rotation axes of the ankle during walking. The results showed that the bionic ankle had variable stiffness properties and could adapt to various road surfaces. It also had rotation axes similar to that of the human ankle, thus restoring the function of the talocrural and subtalar joints. The inclination and deviation angles of the talocrural axis, 86.2° and 75.1°, respectively, as well as the angles of the subtalar axis, 40.1° and 29.9°, were consistent with the literature. Finally, dynamic characteristics were investigated by gait measurements on the same subject, and the flexible bionic ankle prosthesis demonstrated natural gait mechanics during walking in terms of ankle angles and moments.展开更多
This investigation and morphology analysis of porous structure of some kinds of natural materials such as chicken eggshell, partridge eggshell, pig bone, and seeds of mung bean, soja, ginkgo, lotus seed, as well as th...This investigation and morphology analysis of porous structure of some kinds of natural materials such as chicken eggshell, partridge eggshell, pig bone, and seeds of mung bean, soja, ginkgo, lotus seed, as well as the epidermis of apples, with SEM (Scanning Electronic Microscope) showed that natural structures’ pores can be classified into uniform pores, gradient pores and multi pores from the viewpoint of the distribution variation of pore density, size and geometry. Furthermore, an optimal design of porous bearings was for the first time developed based on the gradient configuration of natural materials. The bionic design of porous structures is predicted to be widely developed and applied in the fields of materials and mechanical engineering in the future.展开更多
Unlike most animals,plants fail to move bodily at will.However,movements also occur in every single part of plants out of energy and nutrients needs,spanning from milliseconds to hours on a time scale.And with the gro...Unlike most animals,plants fail to move bodily at will.However,movements also occur in every single part of plants out of energy and nutrients needs,spanning from milliseconds to hours on a time scale.And with the growing understanding of plant movement in the academic community,bionic soft robots based on plant movement principles are increasingly studied and are considered by scientists as a source of inspiration for innovative engineering solutions.In this paper,through the study of the biological morphology,microstructure,and motion mechanism of the flytrap,we developed chambered design rules,and designed and fabricated a gas-driven bionic flytrap blade,intending to investigate its feasibility of performing complex bending deformation.The experimental result shows that the bionic flytrap blade can achieve multi-dimensional bending deformation,and complete the bending and closing action within 2 s.The performance of the bionic flytrap blade fabricated is in high agreement with the real flytrap blade in terms of bending and deformation,achieving an excellent bionic design effect.In this study,the chambered design rules of the bionic flytrap blade were proposed and developed,and the possibility of its deformation was investigated.The effects of different chamber types and different flow channel design precepts on the bending deformation of the bionic flytrap blade were revealed,together with the relationship between the response time and flow rate of the bionic flytrap blade.At last,this study provides new ideas for the study of plant blade motion mechanism in a hope to expand the application fields of bionic robots,especially hope to offer solutions for plant-type robotics.展开更多
Using an electron microscope to observe the microstructure of a porcupine quills cross-section and a bionic method,a new bionic structure was proposed.The performance of the structure in terms of energy absorption,max...Using an electron microscope to observe the microstructure of a porcupine quills cross-section and a bionic method,a new bionic structure was proposed.The performance of the structure in terms of energy absorption,maximum impact force withstood,and impact force efficiency was evaluated using Ansys finite element simulation software to simulate the structure's impact.To examine the impact of ribs on the structural performance of the bionic porcupine quills,a control structure was developed.According to the results of the finite element simulation,the presence of ribs in the Bionic porcupine quills structure can transfer stress uniformly to the overall structure and share stress for some of the rupture-prone regions.Ribs reduce stress concentration in specific areas and increase the impact force efficiency of the structure.The SEA and IFE values of bionic porcupine quills were 30.01 kJ/kg and 84.22%,respectively.The structure is then optimized for parameter design in order to find the optimal structure by response surface in order to improve the structure's SEA and decrease its MIF.In order to evaluate the precision of the response surface,the optimal structure predicted is validated using finite element simulation.展开更多
Inspired by the safe landing of cats falling from high altitudes,a bionic flexible rubber bushing structure is proposed and its motion characteristics are systematically studied to explore its potential application in...Inspired by the safe landing of cats falling from high altitudes,a bionic flexible rubber bushing structure is proposed and its motion characteristics are systematically studied to explore its potential application in the suppression of vibration.The convex hull structure on the bushing surface is abstracted from the cat’s claw pad,and the hyper-viscoelastic model is selected as the constitutive model of the rubber material.In addition,the design with the best vibration damping effect is finally obtained by reasonably adjusting the amount of radial compression and distribution of bionic structures.Finally,under the same conditions,the test results of the dynamic characteristics of the bushing verify the accuracy of the simulation results.Research results show that the convex hull bionic structure designed in this paper can effectively change the motion characteristics of the rubber bushing under various working conditions,which provides new inspiration or potential possibility for the design of rubber bushing in the future.展开更多
Inspired by the crystal microstructure of metals and the bamboo,the bionic porous NiTi structures with the porosities in the range of 75.8%–84.9%were built via selective laser melting(SLM).The compression behavior an...Inspired by the crystal microstructure of metals and the bamboo,the bionic porous NiTi structures with the porosities in the range of 75.8%–84.9%were built via selective laser melting(SLM).The compression behavior and the failure mechanisms of the porous NiTi structures were evaluated.It demonstrated an increase in the elastic modulus and ultimate strength when the porosity was decreased,from 3.06 to 7.66 GPa and from 34.1 to 147.6 MPa,respectively.The relationship between the elastic modulus and the porosity obtained by the finite element analysis exhibited similar tendency with the experiment,and agreed well with the Gibson-Ashby model’s prediction.Based on the theoretical model above and the observation of the deformation processing,the plastic deformation behavior and failure mechanisms of the SLMed porous NiTi structures were analyzed.展开更多
By imitating the body structure and movement mode of the crab in nature,a novel stick–slip piezo-driven positioning platform was proposed by employing the bionic flexible hinge mechanism with a symmetrical structure ...By imitating the body structure and movement mode of the crab in nature,a novel stick–slip piezo-driven positioning platform was proposed by employing the bionic flexible hinge mechanism with a symmetrical structure and two piezoelectric stacks.The structural design and bionic motion principle were discussed,followed by analyzing the feasibility,safety,and output magnification ratio of the bionic flexible hinge mechanism via the stiffness matrix method and finite element simulation.To investigate the output performances of the positioning platform,a prototype was fabricated and an experiment system was established.Stepping characteristics of the positioning platform under various driving voltages were characterized,and the results indicated that the positioning platform could move steadily under various driving voltages.Within 1 s,the differences between the forward and reverse output displacement were less than 3%under different driving frequencies,proving the high bidirectional motion symmetry.The maximum driving speed of 5.44 mm/s was obtained under the driving voltage of 120 V and driving frequency of 5 Hz.In addition,the carrying load capacity of the positioning platform was tested by standard weights,and the results showed that when the carrying load reached 10 N,the driving speed could still reach 60μm/s.展开更多
The goat’s hind limbs play an important role in dampening vibrations caused by ground impact during movement.Inspired by the unique structure of their hind limbs,a novel bionic limb vibration isolator has been develo...The goat’s hind limbs play an important role in dampening vibrations caused by ground impact during movement.Inspired by the unique structure of their hind limbs,a novel bionic limb vibration isolator has been developed to suppress low-frequency vibrations.It consists of the base,the carrying platform,four bionic legs and so on.The bionic legs are made up of rods of varying lengths and springs in different directions to imitate the various shapes of bones such as the femur and patella of the hind limbs of goats and developed muscles such as the biceps and quadriceps.The bionic device was found to have excellent nonlinear stiffness through statics analysis,and could be flexibly adjusted to the work range and load capacity.The bionic vibration isolator offers lower natural frequencies(2.3 Hz),better vibration isolation effect and a wider vibration isolation band than conventional linear vibration isolator.The bionic device can effectively suppress vibrations above 3.2 Hz and reduce the amplitude of random vibrations to more than 90%.In addition,compared to similar bionic vibration isolation devices,the bionic isolator achieves excellent load-bearing capacity in a smaller size,which facilitates its application in practical production.展开更多
基金supported by the National Natural Science Foundation of China(No.52405317)the Special Funds for Science and Technology Programs in Jiangsu Province(BZ2024021)+3 种基金the Natural Science Foundation of Jiangsu Province(BK20241407)the Talent Startup Funding of Chaohu University(KYQD-2023035)the Natural Science Research Projects of Chaohu University(XLZ-202205,XLZ202301)the Horizontal Projects of School-Enterprise Cooperation(No.hxkt20230267).
文摘Wall-climbing robots can stably ascend vertical walls and even ceilings,making them suitable for specialized tasks in high-risk,confined,and harsh conditions.Therefore,they have excellent application prospects and substantial market demand.However,several challenges remain,including limited load-carrying capacity,short operational duration,a high risk of detachment,and the lack of standardized physical and control interfaces for carrying auxiliary equipment to complete missions.This study analyzes the macro and micro structures and movement mechanisms of typical organisms in terms of negative pressure adsorption,hook-and-claw adhesion,dry adhesion,and wet adhesion.The exploration of biological wall-climbing mechanisms is integrated with the adhesion techniques used in practical wall-climbing robots.Additionally,the mechanisms,properties,and typical wall-climbing robots associated with adhesion technologies were investigated,including negative pressure adsorption,hook-and-claw adhesion,bionic dry adhesion,bionic wet adhesion,electrostatic adhesion,and magnetic adhesion.Furthermore,the typical gaits of quadruped and hexapod robots are analyzed,and bionic control techniques such as central pattern generators,neural networks,and compliant control are applied.Finally,the future development trends of wall-climbing robots will be examined from multiple perspectives,including the diversification of bionic mechanisms,the advancement of mechanical structure intelligence,and the implementation of intelligent adaptive control.Moreover,this paper establishes a solid foundation for the innovative design of bionic wall-climbing robots and provides valuable guidance for future advancements.
基金2023 Innovation and Entrepreneurship Training Project of Hunan College Students:Tiger Butterfly—Bionic Manufacturing and Morphology Research(Project No.S202313809022)Key Project of Education Reform of Hunan Provincial Department of Education:Research on Disciplinary Integration Education Model under Intelligence+Empowerment—A Case Study of Robotics and Logistics Management Majors(Project No.HNJG-20231561)。
文摘Based on research into bionic butterflies for environmental detection and ecological management,a scheme was proposed to develop and manufacture a bionic aircraft with two wings inspired by specific butterfly species.A flapping-wing aircraft with a simple structure was designed,and its two-wing design was optimized.The research focused on several key areas:the design and optimization of the wings,the development of the transmission mechanism,hardware design and fabrication,and 3D printing for component manufacturing.This resulted in the bionic replication of the wing shape and structure of the Tiger Papilio butterfly.The final bionic butterfly features a wingspan of 29.5 cm and a total weight of 13.8 g.This project integrates mechatronic principles and provides a valuable reference for advancements in the field of bionic butterflies.Future research could explore the aerodynamic characteristics of wings and innovative design approaches in greater depth.
基金The work is supported by the National Natural Science Foundation of China(Nos.U21A20124 and 52205059)the Key Research and Development Program of Zhejiang Province(No.2022C01039)。
文摘Galloping cheetahs,climbing mountain goats,and load hauling horses all show desirable locomotion capability,which motivates the development of quadruped robots.Among various quadruped robots,hydraulically driven quadruped robots show great potential in unstructured environments due to their discrete landing positions and large payloads.As the most critical movement unit of a quadruped robot,the limb leg unit(LLU)directly affects movement speed and reliability,and requires a compact and lightweight design.Inspired by the dexterous skeleton–muscle systems of cheetahs and humans,this paper proposes a highly integrated bionic actuator system for a better dynamic performance of an LLU.We propose that a cylinder barrel with multiple element interfaces and internal smooth channels is realized using metal additive manufacturing,and hybrid lattice structures are introduced into the lightweight design of the piston rod.In addition,additive manufacturing and topology optimization are incorporated to reduce the redundant material of the structural parts of the LLU.The mechanical properties of the actuator system are verified by numerical simulation and experiments,and the power density of the actuators is far greater than that of cheetah muscle.The mass of the optimized LLU is reduced by 24.5%,and the optimized LLU shows better response time performance when given a step signal,and presents a good trajectory tracking ability with the increase in motion frequency.
基金supported by the Aeronautical Science Foundation of China(2017ZA88001)National Natural Science Foundation of China(11502288)and China Postdoctoral Science Foundation(47661).
文摘The robotic airship is one of the most unique and promising green aircraft,however,as a“lighter-than-air aircraft”and“thermal aircraft”,its long-endurance flight has great difficulties in decreasing drag and controlling buoyancy and pressure under thermal effects.In this work,we reported a robotic airship inspired by the Physalia physalis,imitating its morphology,physiological structure,and biological behaviors.The hull is designed by imitating the morphology of the Physalia physalis,and the gasbags including a helium balloon,two ballonets,and a thermoregulation gasbag are designed by imitating the physiological structure and biological behaviors of the pneumatophore,bladder,and gland of the Physalia physalis,respectively.Experimental results show that the bionic airship has an increase of about 40%in lift-to-drag and decreases the pressure in helium balloon by 47.5%under thermal effects,and has better aerodynamic performances and thermoregulation performances than conventional airships.
基金supported by National Key R&D Program of China(Grant No.2022YFB4600500)Fundamental Research Funds for the Central Universitiesthe Program for Innovation Team of Shaanxi Province of China(Grant No.2023-CX-TD-17).
文摘In engineering,the demand for high energy absorption by structures subjected to impact loads is increasing.Balancing the limited space,manufacturing feasibility,and energy absorption capabilities is a key point in the design of many enclosed structures with energy absorption requirements.To achieve a lightweight design and controllable energy absorption by the structures,within a limited space,this study proposes a bio-inspired double-layer impact-resistant structure that can be manufactured by an additive manufacturing method(powder bed fusion),inspired by the microstructure of a woodpecker’s head.The structure is composed of two basic structural units:a quasi-circular ring and an oblique cylinder.The controllable energy absorption capabilities of the structure were studied through a combination of theoretical analyses,numerical simulations,and physical experiments.The results showed that,for the quasi-circular ring structure,the specific energy absorption range of 13-72 J/g could be effectively regulated by adjusting the structural parameters.The specific energy absorption range of 11-137 J/g could be effectively regulated for oblique cylindrical structures.Finally,the structure was applied to the design of engineering impact-resistant devices,proving the effectiveness of the controllable energy absorption of the structure.Moreover,the design process of the structure was optimized,laying a foundation for the structure to better serve engineering design applications.
基金supported by the Defense Industrial Technology Development Program.
文摘Inspired by natural biomimetic structures exemplified by femoral bones,the shell-infill composite design has emerged as a research focus in structural optimization.However,existing studies predominantly focus on uniform-thickness shell designs and lack robust methodologies for generating high-resolution porous infill configurations.To address these challenges,a novel topology optimization framework for full-scale shell-filled composite structures is developed in this paper.First,a physics-driven,non-uniform partial differential equation(PDE)filter is developed,enabling precise control of variable-thickness shells by establishing explicit mapping relationships between shell thickness and filter radii.Second,this study addresses the convergence inefficiency of traditional full-scale topology optimization methods based on local volume constraints.It is revealed that a reduced influence radius exacerbates algorithm convergence challenges,thereby impeding the design of intricate porous structures.To overcome this bottleneck,a physics-driven stress skeleton generation method is developed.By integrating stress trajectories and rasterization processing,this method constructs an initial density field,effectively guiding material evolution and significantly enhancing convergence in porous structural optimization within the full-scale framework.Classical numerical examples demonstrate that our proposed optimization framework achieves biomimetic non-uniform shell thickness optimization and enables precise control of the shell thickness.Additionally,density preprocessing effectively eliminates intermediate density regions and void aggregation.Moreover,the generated trabecular-like infill patterns with spatially graded porosity,akin to multiscale topology optimization(MTO),provide an innovative solution for multifunctional,lightweight,complex shell-infill composite structures in aerospace and biomedical applications.
基金supported by the National Natural Science Foundation of China(NO.52175069 and NO.52305043).
文摘The wrist unit is crucial in humanoid robots,determining their operational dexterity and precision.To address current challenges such as excessive size,limited Degrees of Freedom(DoFs),and insufficient load capacity,we propose a 3-DoF humanoid wrist inspired by the human forearm and wrist anatomy.This paper explores the principles of wrist bionic design and introduces a parallel mechanism actuated by a brushless DC motor(BLDC)-ball screw to achieve flexion/extension(F/E)and radial flexion/ulnar deviation(R/U),as along with pronation/supination(P/S)through an end-coupling design.We conducted an analysis on the inverse kinematic model and singularities of the humanoid wrist.Additionally,the workspace and motion capabilities of the humanoid wrist were evaluated.A prototype based on this design was built to demonstrate its motion and functional performance,verifying the feasibility and practicality of the humanoid wrist.This research provides a more compact design approach for future humanoid wrist development.
基金National Natural Science Foundation of China (Grant No. 50575008)the Aeronautical Science Foundation of China (Grant No. 05B01004)
文摘High load-bearing efficiency is one of the advantages of biological structures after the evolution of billions of years. Biomimicking from nature may offer the potential for lightweight design. In the viewpoint ofrnechanics properties, the culm of bamboo comprises of two types of cells and the number of the vascular bundles takes a gradient of distribution. A three-point bending test was carried out to measure the elastic modulus. Results show that the elastic modulus of bamboo decreases gradually from the periphery towards the centre. Based on the structural characteristics of bamboo, a bionic cylindrical structure was designed to mimic the gradient distribution of vascular bundles and parenchyma cells. The buckling resistance of the bionic structure was compared with that of a traditional shell of equal mass under axial pressure by finite element simulations. Results show that the load-bearing capacity of bionic shell is increased by 124.8%. The buckling mode of bionic structure is global buckling while that of the conventional shell is local buckling.
基金National Key R&D Program of China(No.2018YFB1105100)National Natural Science Foundation of China(No.51975246)+5 种基金Jilin Province Science and Technology Development Plan(No.YDZJ202101ZYTS134)State Key Laboratory of Automotive Simulation and Control—ziyoutansuoxiangmu(202013)Open Project Program of Key Laboratory for Cross-Scale Micro and Nano Manufacturing,Ministry of Education,Changchun University of Science and Technology(CMNM-KF202109)Program for JLU Science and Technology Innovative Research Team(No.2019TD-34)Interdisciplinary Research Fund for Doctoral Postgraduates of Jilin University(No.101832020DJX052)Interdisciplinary Cultivation Project for Young Teachers and Students(No.415010300078)。
文摘Each specific structure of organisms is the best choice under specific circumstances.The excellent characteristic structures of these organisms have great application potential in the design and multi-functional optimization of energy-absorbing structures such as vehicle collisions,satellite landings,and military equipment.In this paper,using the principle of structural bionics,using the advantages of the honeycomb structure and the light weight and high strength of beetle elytra,four bionic lattice structures are studied:CH,ZPRH,SCH and IBE.Using NiTi shape memory alloy,a unique material as the base material,samples are prepared using selective laser melting(SLM)technology.By comparing the test results of the quasi-static compression test with the results of the numerical simulation,it is found that compared with the other three bionic lattice structures,the SCH structure has the best energy absorption effect in the effective stroke in the test,and the specific energy absorption can reach 6.32 J/g.ZPRH,SCH,and IBE structures not only have good and stable deformation behavior,but also have excellent impact resistance and shape memory properties.The design of these structures provides a reference for the design of anti-shock cushioning structures with self-recovery functions in the future.
基金financially supported by the Postgraduate Research & Practice Innovation Program of Jiangsu Province(Grant No.KYCX18_2311)
文摘The mechanisms of soil structure interaction have drawn much attention in the past years in the installation and operation of jack-up platform. A bionic spudcan produced by biomimetic of egg and snail shell is proposed, and the performance of the penetration and extraction are analyzed by numerical method. The geometric contour of egg and snail shell is measured, and its mathematical model is established respectively. According to the structure of existing spudcan of jack-up platform, three kinds of typical biomimetic spudcan are designed. Furthermore, numerical analysis models of biomimetic spudcan are established respectively to study the soil structure interaction mechanism in the process of penetration and extraction, and contrastive analysis of resistance characteristics are carried out. To conclude, the results show that the biomimetic spudcan facilitates the platform installation, and it is also beneficial to the improvement of the bearing capacity of spudcan.
基金supported by the National Key Research and Development Program of China(No.2018YFC2001300)the National Natural Science Foundation of China(No.52005209,91948302,No.91848204,No.52021003)the Natural Science Foundation of Jilin Province(No.20210101053JC,No.20220508130RC).
文摘A variety of prosthetic ankles have been successfully developed to reproduce the locomotor ability for lower limb amputees in daily lives. However, they have not been shown to sufficiently improve the natural gait mechanics commonly observed in comparison to the able-bodied, perhaps due to over-simplified designs of functional musculoskeletal structures in prostheses. In this study, a flexible bionic ankle prosthesis with joints covered by soft material inclusions is developed on the basis of the human musculoskeletal system. First, the healthy side ankle–foot bones of a below-knee amputee were reconstructed by CT imaging. Three types of polyurethane rubber material configurations were then designed to mimic the soft tissues around the human ankle, providing stability and flexibility. Finite element simulations were conducted to determine the proper design of the rubber materials, evaluate the ankle stiffness under different external conditions, and calculate the rotation axes of the ankle during walking. The results showed that the bionic ankle had variable stiffness properties and could adapt to various road surfaces. It also had rotation axes similar to that of the human ankle, thus restoring the function of the talocrural and subtalar joints. The inclination and deviation angles of the talocrural axis, 86.2° and 75.1°, respectively, as well as the angles of the subtalar axis, 40.1° and 29.9°, were consistent with the literature. Finally, dynamic characteristics were investigated by gait measurements on the same subject, and the flexible bionic ankle prosthesis demonstrated natural gait mechanics during walking in terms of ankle angles and moments.
文摘This investigation and morphology analysis of porous structure of some kinds of natural materials such as chicken eggshell, partridge eggshell, pig bone, and seeds of mung bean, soja, ginkgo, lotus seed, as well as the epidermis of apples, with SEM (Scanning Electronic Microscope) showed that natural structures’ pores can be classified into uniform pores, gradient pores and multi pores from the viewpoint of the distribution variation of pore density, size and geometry. Furthermore, an optimal design of porous bearings was for the first time developed based on the gradient configuration of natural materials. The bionic design of porous structures is predicted to be widely developed and applied in the fields of materials and mechanical engineering in the future.
基金the National Natural Science Foundation of China,51905084the Natural Science Foundation of Heilongjiang Province,YQ2021E002.
文摘Unlike most animals,plants fail to move bodily at will.However,movements also occur in every single part of plants out of energy and nutrients needs,spanning from milliseconds to hours on a time scale.And with the growing understanding of plant movement in the academic community,bionic soft robots based on plant movement principles are increasingly studied and are considered by scientists as a source of inspiration for innovative engineering solutions.In this paper,through the study of the biological morphology,microstructure,and motion mechanism of the flytrap,we developed chambered design rules,and designed and fabricated a gas-driven bionic flytrap blade,intending to investigate its feasibility of performing complex bending deformation.The experimental result shows that the bionic flytrap blade can achieve multi-dimensional bending deformation,and complete the bending and closing action within 2 s.The performance of the bionic flytrap blade fabricated is in high agreement with the real flytrap blade in terms of bending and deformation,achieving an excellent bionic design effect.In this study,the chambered design rules of the bionic flytrap blade were proposed and developed,and the possibility of its deformation was investigated.The effects of different chamber types and different flow channel design precepts on the bending deformation of the bionic flytrap blade were revealed,together with the relationship between the response time and flow rate of the bionic flytrap blade.At last,this study provides new ideas for the study of plant blade motion mechanism in a hope to expand the application fields of bionic robots,especially hope to offer solutions for plant-type robotics.
基金supported by the National Natural Science Foundation of China(No.11972158)the Postgraduate Scientific Research Innovation Project of Hunan Province(No.CX20221044)the Military Commission Science and Technology Committee Basic Strengthening Program Technology Fund(No.2020-JCJQ-JJ-356)and(No.2019-JCJQ-JJ-150).
文摘Using an electron microscope to observe the microstructure of a porcupine quills cross-section and a bionic method,a new bionic structure was proposed.The performance of the structure in terms of energy absorption,maximum impact force withstood,and impact force efficiency was evaluated using Ansys finite element simulation software to simulate the structure's impact.To examine the impact of ribs on the structural performance of the bionic porcupine quills,a control structure was developed.According to the results of the finite element simulation,the presence of ribs in the Bionic porcupine quills structure can transfer stress uniformly to the overall structure and share stress for some of the rupture-prone regions.Ribs reduce stress concentration in specific areas and increase the impact force efficiency of the structure.The SEA and IFE values of bionic porcupine quills were 30.01 kJ/kg and 84.22%,respectively.The structure is then optimized for parameter design in order to find the optimal structure by response surface in order to improve the structure's SEA and decrease its MIF.In order to evaluate the precision of the response surface,the optimal structure predicted is validated using finite element simulation.
基金The authors gratefully acknowledge the financial supports from the Jilin Provincial Scientific and Technological Department(20220201123GX).
文摘Inspired by the safe landing of cats falling from high altitudes,a bionic flexible rubber bushing structure is proposed and its motion characteristics are systematically studied to explore its potential application in the suppression of vibration.The convex hull structure on the bushing surface is abstracted from the cat’s claw pad,and the hyper-viscoelastic model is selected as the constitutive model of the rubber material.In addition,the design with the best vibration damping effect is finally obtained by reasonably adjusting the amount of radial compression and distribution of bionic structures.Finally,under the same conditions,the test results of the dynamic characteristics of the bushing verify the accuracy of the simulation results.Research results show that the convex hull bionic structure designed in this paper can effectively change the motion characteristics of the rubber bushing under various working conditions,which provides new inspiration or potential possibility for the design of rubber bushing in the future.
基金This work was financially supported by the Natural Science Foundation of Jilin Province(No.20220101216JC)the National Natural Science Foundation of China(No.52235006)+1 种基金the National Natural Science Foundation of China(No.52025053)the National Natural Science Foundation of China(No.52105303).
文摘Inspired by the crystal microstructure of metals and the bamboo,the bionic porous NiTi structures with the porosities in the range of 75.8%–84.9%were built via selective laser melting(SLM).The compression behavior and the failure mechanisms of the porous NiTi structures were evaluated.It demonstrated an increase in the elastic modulus and ultimate strength when the porosity was decreased,from 3.06 to 7.66 GPa and from 34.1 to 147.6 MPa,respectively.The relationship between the elastic modulus and the porosity obtained by the finite element analysis exhibited similar tendency with the experiment,and agreed well with the Gibson-Ashby model’s prediction.Based on the theoretical model above and the observation of the deformation processing,the plastic deformation behavior and failure mechanisms of the SLMed porous NiTi structures were analyzed.
基金This work was supported by the National Natural Science Foundation of China(Grant No.52075221)the Research Foundation of Education Department of Jilin Province,China(Grant No.JJKH20231153KJ)the Fundamental Research Funds for the Central Universities(2019-2023).
文摘By imitating the body structure and movement mode of the crab in nature,a novel stick–slip piezo-driven positioning platform was proposed by employing the bionic flexible hinge mechanism with a symmetrical structure and two piezoelectric stacks.The structural design and bionic motion principle were discussed,followed by analyzing the feasibility,safety,and output magnification ratio of the bionic flexible hinge mechanism via the stiffness matrix method and finite element simulation.To investigate the output performances of the positioning platform,a prototype was fabricated and an experiment system was established.Stepping characteristics of the positioning platform under various driving voltages were characterized,and the results indicated that the positioning platform could move steadily under various driving voltages.Within 1 s,the differences between the forward and reverse output displacement were less than 3%under different driving frequencies,proving the high bidirectional motion symmetry.The maximum driving speed of 5.44 mm/s was obtained under the driving voltage of 120 V and driving frequency of 5 Hz.In addition,the carrying load capacity of the positioning platform was tested by standard weights,and the results showed that when the carrying load reached 10 N,the driving speed could still reach 60μm/s.
基金This research was funded by the the Science and Technology Development Program of Jilin Province,China(Grant No.20230101117JC)National Natural Science Foundation of China(Grant No.51775234,91748211,51305157)the Science and Technology Development Program of Jilin Province,China(Grant No.20190302101GX,20180101090JC).
文摘The goat’s hind limbs play an important role in dampening vibrations caused by ground impact during movement.Inspired by the unique structure of their hind limbs,a novel bionic limb vibration isolator has been developed to suppress low-frequency vibrations.It consists of the base,the carrying platform,four bionic legs and so on.The bionic legs are made up of rods of varying lengths and springs in different directions to imitate the various shapes of bones such as the femur and patella of the hind limbs of goats and developed muscles such as the biceps and quadriceps.The bionic device was found to have excellent nonlinear stiffness through statics analysis,and could be flexibly adjusted to the work range and load capacity.The bionic vibration isolator offers lower natural frequencies(2.3 Hz),better vibration isolation effect and a wider vibration isolation band than conventional linear vibration isolator.The bionic device can effectively suppress vibrations above 3.2 Hz and reduce the amplitude of random vibrations to more than 90%.In addition,compared to similar bionic vibration isolation devices,the bionic isolator achieves excellent load-bearing capacity in a smaller size,which facilitates its application in practical production.
