Journal of Bionic Engineering

Plants as concept generators for biomimetic light-weight structures with variable stiffness and self-repair mechanisms

Thomas Speck^1,2, Tom Masselter ², Bettina Prüm², Olga Speck¹, Rolf Luchsinger ¹, Siegfried Fink ⁴

J4. 2004, 1 (4): 199-205. DOI:

Abstract ( 1705 )

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Plants possess many structural and functional properties that have a high potential to serve as concept generators for the production of biomimetic technical materials and structures. We present data on two features of plants (variable stiffness due to pressure changes in cellular structures and rapid self-repair functions) that may be used as models for biomimetic projects.

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Sliding resistance of plates with bionic bumpy surface against soil

LI Jian-qiao ¹, SUN Jiu-rong ², REN Lu-quan ¹, CHEN Bing-cong ¹

J4. 2004, 1 (4): 207-214. DOI:

Abstract ( 1650 )

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The non-smooth surface morphology of dung beetle, Copris ochus, was analyzed. The bulldozing plates with bionic geometric non-smooth or the chemical uneven surface were designed for the soil sliding test based on the simulation of the bumpy surface of the dung beetle. Special black metals—with different contents of alloys of manganese, silicon, chromium, copper and rare earth—were developed for making geometric non-smooth and chemical uneven surfaces by means of surface welding at the surfaces of a middle carbon steel plate. Four metals, with different surface properties including hardness and water contact angle were used to make the bulldozing plates for measuring the soil sliding resistance. Test results of soil sliding resistance indicate that all the geometric non-smooth plates and the chemical uneven plates reducing soil friction. Considering the materials and surface morphology, the bionic plate can reduce the soil sliding resistance from 18.1 % up to 42.2%, compared to the traditional smooth bulldozing plate made from middle carbon steel. The test results also show that the smaller the normal load, the greater effect on resistance reduction by the bionic non-smooth surface plates.

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Highly bioactive nano-hydroxyapatite/partially stabilized zirconia ceramics

WANG Qing-liang, GE Shi-rong, ZHANG De-kun

J4. 2004, 1 (4): 215-220. DOI:

Abstract ( 1263 )

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Nanocrystalline hydroxyapatite (HA) powders have been synthesized by precipitation using Ca(NO3)2 • 4H2O and (NH4)2 HPO4 at room temperature and atmospheric pressure. Nanocomposites of HA and partially stabilized zirconia (HA/PSZ) were sintered at atmospheric pressure and 1300℃ for 2h in air. The preparation techniques, structure and me-chanical properties of these materials were characterized. The addition of nanosized PSZ reinforcing phase to HA may lead to an improvement of the macro and micro mechanical properties and not affect its biocompatibility and bioactivity. The bending strength, fracture toughness and nano-hardness were near to or greater than those for human cortical bone and human tooth (dentine and enamel). The composite was incubated in a fresh human plasma which confirmed the bioactivity of nanosized HA/PSZ materials. The bonding reaction between HA/PSZ ceramic and the plasma proteins was found, and he-matopoietic cell phosphatase (HCP) layers formed on surface of each composite incubated in human plasma for two weeks. The diameter of a single HCP globule was less than 100 nm. Furthermore, the precipitating mechanism investigation was carried out through a comparative experiment in this paper.

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Factors impacting nanoindentation testing results of the cuticle of dung beetle Copris ochus Motschulsky

TONG Jin ¹, SUN Ji-yu ¹, CHEN Dong-hui ¹, ZHANG Shu-jun ²

J4. 2004, 1 (4): 221-230. DOI:

Abstract ( 1657 )

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The cuticle of dung beetle is a layered composite material in micro- or nano-scale. Dung beetle can fly, walk and dig. It can shovel and compact dung of mammals into balls. It use foreleg to walk, midleg and hindleg to hold and impel dung ball. Its two foreleges as digging legs are developed. The factors impacting the nanoindentation testing results of the femur cuticle of forelegs of dung beetle Copris ochus Motschulsky were examined. The nanomechanical test instrument used for the tests was Hysitron nanomechanical system. The results shown that the holding time and loading time are important factors im-pacting the accuracy of such indentation properties as reduced modulus (E_r) and the harness ( H ) of the femur cuticle of the forelegs of dung beetle Copris ochus Motschulsky in nanoscale. There exists a threshold holding time of 20 s for the reduced modulus of the femur cuticle. The tests of nanoindentation creep property and the regression analysis of relationship between the depth increment at the maximum load and the time further confirmed the correction of the above threshold holding time. There exist visco-elastic-plastic behaviour and creep phenomenon in the femur cuticle during indenting. Its creep property during the holding procedure at maximum load can be regressed by a general logarithmic equation. The equation fitted by the testing data is Δh = 54.834 52 ln(0.007 23t +1.004 86), where, Δh is the depth increment at the maximum load and t is the time.

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Geometric design of crab-like climbing and walking robots

LIU An-min, David Howard

J4. 2004, 1 (4): 231-240. DOI:

Abstract ( 1286 )

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This paper considers the geometric design of crab-like walkers and climbers, without decoupling leg design from overall machine design. Crab-like machines represent an important sub-class of multi-legged robots, being particularly well suited to crossing difficult terrains. Firstly, the kinematic configurations and constraints are described, which determine the machine's kinematic characteristics. The influence of the design parameters on the kinematic workspace is discussed. Finally, a two stage design methodology is presented, comprising kinematic design and design optimisation, the latter being based on the use of design maps rather than numerical optimisation. The performance measures considered during design optimisation include kinematic, static and quasi-static measures.

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Computer simulation of rolling wear on bionic non-smooth convex surfaces

HAN Zhi-wu ¹, LIU Zu-bin ², YANG Zhuo-juan ¹, YAN Yu-ying ³, REN Lu-quan ¹

J4. 2004, 1 (4): 241-247. DOI:

Abstract ( 1689 )

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The study of bionics has found that the skins of many burrow animals which live in soil and stone conditions have an anti wear function, and which is related to their body surfaces’ non-smooth morphology. In the present study, bionic non-smooth surfaces are used in roll surface design, and roll models with convex non-smooth surfaces are developed. The rolling wear of non-smooth roll in steel rolling is simulated by the FEM software-ANSYS. The equivalent stress, the node friction stress, and the node contact pressure between the roll and the rolling piece are calculated; and the anti-wear mechanism is analyzed.

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Super-hydrophobic characteristics of butterfly wing surface

CONG Qian, CHEN Guang-hua, FANG Yan, REN Lu-quan

J4. 2004, 1 (4): 249-255. DOI:

Abstract ( 2312 )

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Many biological surface are hydrophobic because of their complicated composition and surface microstructure. Eleven species (four families) of butterflies were selected to study their micro-, nano-structure and super-hydrophobic characteristic by means of Confocal Light Microscopy, Scanning Electron Microscopy and Contact Angle Measurement. The contact an-gles of water droplets on the butterfly wing surface were consistently measured to be about 150˚ and 100˚ with and without the squamas, respectively. The dust on the surface can be easily cleaned by moving spherical droplets when the inclining angle is larger than 3˚. It can be concluded that the butterfly wing surface possess a super-hydrophobic, water-repellent, self-cleaning, or "Lotus-effect" characteristic. The contact angle measurement of water droplets on the wing surface with and without the squamas showed that the water-repellent characteristic is a consequence of the microstructure of the squamas. Each water droplet (diameter 2 mm) can cover about 700 squamas with a size of 40 μm×80 μm of each squama. The regular riblets with a width of 1000 nm to 1500 nm are clearly observed on each single squama. Such nanostructure should play a very important role in their super-hydrophobic and self-cleaning characteristic.

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