Structural design inspired by beetle elytra and its mechanical properties

Abstract: Based on the particularity analysis of coal mine accidents and fire occurred, a rescue robot is designed for coal mine and fire rescue. This robot adopts four tracks composite drive mechanism with front and rear machine hinged, and has good climbing, obstacle capability, the ground adaptability, mechanical properties, waterproof, fireproof, explosion-proof and other functions. It carries oxygen, food, lighting, water, self-help equipment and first-aid medicines to achieve effective relief.

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Multilayer stag beetle elytra perform better under external loading via non-symmetric bending properties

Journal of The Royal Society Interface ◽

10.1098/rsif.2018.0427 ◽

2018 ◽

Vol 15 (144) ◽

pp. 20180427 ◽

Cited By ~ 4

Author(s):

Lakshminath Kundanati ◽

Stefano Signetti ◽

Himadri S. Gupta ◽

Michele Menegon ◽

Nicola M. Pugno

Keyword(s):

Mechanical Properties ◽

Mechanical Behaviour ◽

Composite Structures ◽

Flexural Modulus ◽

Bottom Layer ◽

Multilayered Structure ◽

External Loading ◽

Multifunctional Composites ◽

Bending Properties ◽

Beetle Elytra

Insect cuticle has drawn a lot of attention from engineers because of its multifunctional role in the life of insects. Some of these cuticles have an optimal combination of lightweight and good mechanical properties, and have inspired the design of composites with novel microstructures. Among these, beetle elytra have been explored extensively for their multilayered structure, multifunctional roles and mechanical properties. In this study, we investigated the bending properties of elytra by simulating their natural loading condition and comparing it with other loading configurations. Further, we examined the properties of their constitutive bulk layers to understand the contribution of each one to the overall mechanical behaviour. Our results showed that elytra are graded, multilayered composite structures that perform better in natural loading direction in terms of both flexural modulus and strength which is likely an adaptation to withstand loads encountered in the habitat. Experiments are supported by analytical calculations and finite element method modelling, which highlighted the additional role of the relatively stiff external exocuticle and of the flexible thin bottom layer in enhancing flexural mechanical properties. Such studies contribute to the knowledge of the mechanical behaviour of this natural composite material and to the development of novel bioinspired multifunctional composites and for optimized armours.

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Research on the Preparation of HA/PEEK Gradient Composites by Impregnation Method and the Biosecurity

Materials Science Forum ◽

10.4028/www.scientific.net/msf.893.35 ◽

2017 ◽

Vol 893 ◽

pp. 35-42 ◽

Cited By ~ 1

Author(s):

Rui Ma ◽

Ling Jun Dai ◽

Lin Wang ◽

Yu Dian Song

Keyword(s):

Mechanical Properties ◽

Bone Formation ◽

Structural Design ◽

Injection Moulding ◽

In Vitro Cytotoxicity ◽

Leach Liquor ◽

Cytotoxicity Test ◽

Impregnation Method ◽

The Poor

This study prepares the HA/PEEK gradient composites with special structural design by impregnation method, which eases the contradiction of the HA/PEEK composites between the lack of bioactivity due to low HA contents and the poor mechanical properties due to high HA contents, and effectively improves the bioactivity and mechanical properties of the PEEK-based materials, and then evaluates the biosecurity of HA/PEEK gradient composites. The main functional cell of bone formation—osteoblast is adopted for the co-culture with PEEK, HA/PEEK gradient composites and the leach liquor, and the effects of PEEK and HA/PEEK gradient composites on the proliferative functions of osteoblast are studied by in vitro cytotoxicity test. The results show that no harmful admixtures are produced in the process of injection moulding, and the leach liquors of PEEK and HA/PEEK gradient composites have no effects on the proliferative functions of osteoblast, with good osteoblast compatibility.

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Mechanical Properties and Calculation Model of Eco-Composite Wall

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.256-259.836 ◽

2012 ◽

Vol 256-259 ◽

pp. 836-839

Author(s):

Li Na Hou ◽

Gang Jing

Keyword(s):

Mechanical Properties ◽

Structural Characteristic ◽

Structural Design ◽

Mechanical Model ◽

Calculation Model ◽

Wall Structure ◽

Main Bearing ◽

Collaborative Performance ◽

Study Results ◽

Composite Wall

Eco-composite wall, as the main bearing member of the eco-composite wall structure, has unique structural characteristic compared with traditional wall. The constructional features, mechanical properties and collaborative performance of the wall are analyzed. Based on this, the three-stage mechanical model of eco-composite wall is put forward. The study results indicate that the eco-composite wall has unique structural characteristic, which makes the structure in possession of several seismic defending lines and have good seismic performance. The three-stage mechanical model is proved reasonable and applicable in structural design.

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Structural Design and Experimental Study of a New Vacuum Vulcanizing Machine

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.427-429.166 ◽

2013 ◽

Vol 427-429 ◽

pp. 166-169

Author(s):

Cai Jun Liu ◽

Xu Juan Wang ◽

Xu Wei

Keyword(s):

Mechanical Properties ◽

Structural Design ◽

Production Efficiency ◽

Physical And Mechanical Properties ◽

Structure Characteristics ◽

High Production Efficiency ◽

New Type ◽

High Production ◽

High Degree ◽

Machine Structure

This paper introduces a new type vacuum vulcanizing machine structure characteristics, the machine can realize the automatic mold, mold release, flip, ejector, has a high degree of automation, high precision products, high production efficiency; and to study the model of vacuumizing plate vulcanizing machine and physical and mechanical properties of ordinary vulcanization machine the influence of the vulcanizate by experiment.

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The Acrylic Spike Design of British Pavilion, 2010 EXPO

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.255-260.1558 ◽

2011 ◽

Vol 255-260 ◽

pp. 1558-1562

Author(s):

De Can Mao ◽

Wei Xing Li ◽

Marco Cerini

Keyword(s):

Mechanical Properties ◽

Wind Tunnel ◽

Structural Design ◽

Wind Load ◽

Structure Design ◽

Creep Tests ◽

Load Effect ◽

Service Period ◽

Structural Engineers

Innovative architectural acrylic spike application leads to a great challenge for structural engineers for the structural design of Shanghai Expo British pavilion. A set of mechanical properties has been proposed to provide a reference for the application of acrylic material in structure design area. The wind tunnel, fatigue and creep tests and research for acrylic spike were carried out to determine the wind load effect of spike and ensure that the spikes are not damaged under fatigue and creep effects during 1.5 years service period.

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Evaluation Procedures for Irradiation Effects and Sodium Environmental Effects for the Structural Design of Japanese Fast Breeder Reactors

Journal of Pressure Vessel Technology ◽

10.1115/1.1338119 ◽

2000 ◽

Vol 123 (1) ◽

pp. 49-57 ◽

Cited By ~ 20

Author(s):

Tai Asayama ◽

Yasuhiro Abe ◽

Noriko Miyaji ◽

Mamoru Koi ◽

Tomohiro Furukawa ◽

...

Keyword(s):

Mechanical Properties ◽

Environmental Effects ◽

Structural Design ◽

Neutron Fluence ◽

Evaluation Procedure ◽

Fast Breeder Reactor ◽

Irradiation Effects ◽

Creep Life ◽

Fast Breeder Reactors ◽

Breeder Reactors

In the structural design of fast breeder reactors, irradiation effects and sodium environmental effects on structural materials have to be taken into account. In this paper, firstly, an evaluation procedure for irradiation effects on the mechanical properties of 316FR (FBR Grade 316 stainless steel), which is a newly developed stainless steel for the Japanese demonstration fast breeder reactor, is proposed. The procedure gives a limit of accumulated fast neutron fluence E>0.1 MeV as a function of temperature, so that the minimum tensile fracture elongation of 10 percent, which is the threshold for material to stay ductile, is maintained. Furthermore, the procedure determined a creep life reduction factor and a creep rate increase factor as a function of accumulated thermal neutron fluence E<0.4 eV, within the limitation of the accumulated fast neutron fluence, to account for the creep life reduction and the increase of creep rate due to irradiation. Secondly, an evaluation procedure for sodium environmental effects on the integrity of 316FR and modified 9Cr-1Mo steel was proposed. It gave a corrosion allowance as a function of temperature, oxygen content, and service time, based on corrosion tests. It determined that no correction factors that correspond to sodium environment on design allowable stresses, etc., are needed, because no adverse effects of sodium on the mechanical properties of 316FR and modified 9Cr-1Mo steel were to be expected in the service conditions of FBRs. Both the procedures have been incorporated into the Japanese Elevated Temperature Structural Design Guide for Demonstration Fast Breeder Reactor.

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