Venus flytrap can sense the very small insects that touch its tactile receptors,known as trigger hairs,and thus capture prey to maintain its nutrient demand.However,there are few studies on the trigger hair and its mo...Venus flytrap can sense the very small insects that touch its tactile receptors,known as trigger hairs,and thus capture prey to maintain its nutrient demand.However,there are few studies on the trigger hair and its morphological structure and material properties are not fully understood.In this study,the trigger hair is systematically characterized with the help of diff erent instruments.Results show that trigger hair is a special cantilever beam structure and it has a large longitudinal diameter ratio.Besides,it is composed of a hair lever and a basal podium,and there is a notch near the hair base.The crosssection of the trigger hair is approximately a honeycomb structure,which is composed of many holes.Methods to measure mechanical properties of trigger hair are introduced in this paper.Based on the mechanical tests,trigger hair proved to be a variable stiff ness structure and shows a high sensitivity to the external force.These features can provide supports for the understanding of the high-sensitivity sensing mechanism of trigger hairs from the perspective of structure and material,and off er inspirations for the development of high-performance tactile sensors.展开更多
Past researches have shown that the non-smooth body surfaces of soil burrowing animals help to reduce soil resistance. In this research, this concept of bionic non-smooth surface was applied to disc ploughs and an exp...Past researches have shown that the non-smooth body surfaces of soil burrowing animals help to reduce soil resistance. In this research, this concept of bionic non-smooth surface was applied to disc ploughs and an experiment was conducted in an indoor soil bin to find out the effects of different bionic units on reducing soil resistance to disc ploughing. Horizontal force acting on the disc plough during soil deformation was measured using a 5 kN sensor. Convex and concave bionic units were used and the material used for making convex ones is ultra high molecular weight polyethylene (UHMWPE) which is hydrophobic. From the experiment results, higher or deeper bionic units always resulted in less soil resistance. Convex bionic units gave the highest resistance reduction reaching a maximum of 19% reduction (from 1715.36 N to 1383.65 N) compared to concave bi-onic units. Also, samples with a bionic unit density of 30% gave the highest resistance reduction compared to the other two, which were either plain or had 10% density. In conclusion, the concept of bionic non-smooth units can be applied to disc ploughs in order to reduce soil resistance.展开更多
Inspired by the co-coupling of the non-smooth structure and the waxy layer inducing the hydrophobicity of dragonfly wing surface,we developed a simple and versatile method to fabricate a superhydrophobic surface with ...Inspired by the co-coupling of the non-smooth structure and the waxy layer inducing the hydrophobicity of dragonfly wing surface,we developed a simple and versatile method to fabricate a superhydrophobic surface with the dragonfly wing structures.In this work,Ag nanorods grew on highly ordered anodic aluminum oxide(AAO) surface via a galvanic reduction approach.Then the AAO-Ag multilayer was fabricated.Furthermore,the surface free energy of AAO-Ag multilayer was reduced by modifying with perfluorodecanethiol.The modified AAO-Ag multilayer was superhydrophobic and the static contact angle reached as high as 168°.X-ray photoelectron spectra(XPS) were used to characterize the chemical structure of the obtained products.The morphologies of AAO-Ag multilayer was similar to microstructure of dragonfly wing surface and presented hierarchical rough structure.The results showed that the co-coupling of the rough structure and low surface free energy induced the superhydrophobic performance of the AAO-Ag multilayer surface.展开更多
Walking on the water surface is an effective method for miniature robots to transport payloads with dramatically decreased interfacial drag. Current aquatic robots reported are generally actuated by a beam of focused ...Walking on the water surface is an effective method for miniature robots to transport payloads with dramatically decreased interfacial drag. Current aquatic robots reported are generally actuated by a beam of focused light that can trigger asymmetrical deformation, enabling the directional movement through horizontal momentum transfer of photoinduced actuation force to the water. However, the operations are heavily dependent on manual manipulation of the focused light, making the long-term actuation and application of the aquatic robots in vast scenarios challenging. Herein, we developed a kind of water striderinspired robot that can autonomously manage the motion on the water surface under solar irradiation, with their direction steerable by a magnetic field. The motion of this bioinspired robot on the water surface was achieved by the use of a solar cell panel as a driving module to enable propulsive motion based on the conversion of light-electric-mechanical energies. The superhydrophobic design of its leg surfaces enables the aquatic robots with weight-bearing and drag-reducing abilities. With the assistance of magnetic navigation, the bioinspired robot can continuously and controllably locomote to the oily spill floating on the water body and collect them with high efficiency. For further demonstration, the treatment of oil spills in a campus pool with high efficiency has also been achieved. This on-site oil-spill treating strategy, taking advantage of a home-made bioinspired robot actuated by natural sunlight under magnetic steering, shows great potential applications in water-body remediation.展开更多
基金supported by the National Natural Science Foundation of China[Grant no.52005355]Postdoctoral Science Foundation of China[Grant no.2020M671575]+2 种基金Opening Project of the Key Laboratory of Bionic Engineering(Ministry of Education),Jilin University[Grant no.KF20200004]Opening Project of the Key Laboratory of Advanced Robotics of Jiangsu Provience[Grant no.JAR201901]Natural Natural Science Research Project of Higher Education of Jiangsu Province[Grant no.20KJB460007].
文摘Venus flytrap can sense the very small insects that touch its tactile receptors,known as trigger hairs,and thus capture prey to maintain its nutrient demand.However,there are few studies on the trigger hair and its morphological structure and material properties are not fully understood.In this study,the trigger hair is systematically characterized with the help of diff erent instruments.Results show that trigger hair is a special cantilever beam structure and it has a large longitudinal diameter ratio.Besides,it is composed of a hair lever and a basal podium,and there is a notch near the hair base.The crosssection of the trigger hair is approximately a honeycomb structure,which is composed of many holes.Methods to measure mechanical properties of trigger hair are introduced in this paper.Based on the mechanical tests,trigger hair proved to be a variable stiff ness structure and shows a high sensitivity to the external force.These features can provide supports for the understanding of the high-sensitivity sensing mechanism of trigger hairs from the perspective of structure and material,and off er inspirations for the development of high-performance tactile sensors.
基金supported by the National Natural Science Foundation of China (Grant No 50175045)National High Technology Research and Development Program of China (‘863’ Project) (Grant No 2010AA101401-3)the scientific and technological development plan of Jilin Province, China (Grant No 20050539)
文摘Past researches have shown that the non-smooth body surfaces of soil burrowing animals help to reduce soil resistance. In this research, this concept of bionic non-smooth surface was applied to disc ploughs and an experiment was conducted in an indoor soil bin to find out the effects of different bionic units on reducing soil resistance to disc ploughing. Horizontal force acting on the disc plough during soil deformation was measured using a 5 kN sensor. Convex and concave bionic units were used and the material used for making convex ones is ultra high molecular weight polyethylene (UHMWPE) which is hydrophobic. From the experiment results, higher or deeper bionic units always resulted in less soil resistance. Convex bionic units gave the highest resistance reduction reaching a maximum of 19% reduction (from 1715.36 N to 1383.65 N) compared to concave bi-onic units. Also, samples with a bionic unit density of 30% gave the highest resistance reduction compared to the other two, which were either plain or had 10% density. In conclusion, the concept of bionic non-smooth units can be applied to disc ploughs in order to reduce soil resistance.
基金supported by the National Natural Science Foundation of China(50875108 and 20903044)the Specialized Research Fund for the Doctoral Program of Higher Education of China(20100061110022)the Open Project Program of Key Laboratory for Bionic Engineering of Ministry of Education
文摘Inspired by the co-coupling of the non-smooth structure and the waxy layer inducing the hydrophobicity of dragonfly wing surface,we developed a simple and versatile method to fabricate a superhydrophobic surface with the dragonfly wing structures.In this work,Ag nanorods grew on highly ordered anodic aluminum oxide(AAO) surface via a galvanic reduction approach.Then the AAO-Ag multilayer was fabricated.Furthermore,the surface free energy of AAO-Ag multilayer was reduced by modifying with perfluorodecanethiol.The modified AAO-Ag multilayer was superhydrophobic and the static contact angle reached as high as 168°.X-ray photoelectron spectra(XPS) were used to characterize the chemical structure of the obtained products.The morphologies of AAO-Ag multilayer was similar to microstructure of dragonfly wing surface and presented hierarchical rough structure.The results showed that the co-coupling of the rough structure and low surface free energy induced the superhydrophobic performance of the AAO-Ag multilayer surface.
基金supported by the National Natural Science Foundation of China (Grant Nos. 22102104, 52175550)the Natural Science Foundation of Shenzhen Science and Technology Commission (Grant Nos. RCBS20200714114920190, JCYJ20220531103409021)+2 种基金Guangdong Basic and Applied Basic Research Foundation (Grant No. 2021A1515010672)the Specific Research Project of Guangxi for Research Bases and Talents (Grant No. 2022AC21200)the Opening Project of the Key Laboratory of Bionic Engineering (Ministry of Education), Jilin University (Grant No. KF20211002)。
文摘Walking on the water surface is an effective method for miniature robots to transport payloads with dramatically decreased interfacial drag. Current aquatic robots reported are generally actuated by a beam of focused light that can trigger asymmetrical deformation, enabling the directional movement through horizontal momentum transfer of photoinduced actuation force to the water. However, the operations are heavily dependent on manual manipulation of the focused light, making the long-term actuation and application of the aquatic robots in vast scenarios challenging. Herein, we developed a kind of water striderinspired robot that can autonomously manage the motion on the water surface under solar irradiation, with their direction steerable by a magnetic field. The motion of this bioinspired robot on the water surface was achieved by the use of a solar cell panel as a driving module to enable propulsive motion based on the conversion of light-electric-mechanical energies. The superhydrophobic design of its leg surfaces enables the aquatic robots with weight-bearing and drag-reducing abilities. With the assistance of magnetic navigation, the bioinspired robot can continuously and controllably locomote to the oily spill floating on the water body and collect them with high efficiency. For further demonstration, the treatment of oil spills in a campus pool with high efficiency has also been achieved. This on-site oil-spill treating strategy, taking advantage of a home-made bioinspired robot actuated by natural sunlight under magnetic steering, shows great potential applications in water-body remediation.