Journal of Bionic Engineering

A Biomimetic Climbing Robot Based on the Gecko

Carlo Menon, Metin Sitti

J4. 2006, 3 (3): 115-125. DOI:

Abstract ( 1525 )

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The excellent climbing performance of the gecko is inspiring engineers and researchers for the design of artificial systems aimed at moving on vertical surfaces. Climbing robots could perform many useful tasks such as surveillance, inspection, repair, cleaning, and exploration. This paper presents and discusses the design, fabrication, and evaluation of two climbing robots which mimic the gait of the gecko. The first robot is designed considering macro-scale operations on Earth and in space. The second robot, whose motion is controlled using shape memory alloy actuators, is designed to be easily scaled down for micro-scale applications. Proposed bionic systems can climb up 65 degree slopes at a speed of 20 mm•s⁻¹.

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Computational Models to Synthesize Human Walking

Lei Ren ^1,2, David Howard ² , Laurence Kenney ²

J4. 2006, 3 (3): 127-138. DOI:

Abstract ( 1320 )

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The synthesis of human walking is of great interest in biomechanics and biomimetic engineering due to its predictive ca-pabilities and potential applications in clinical biomechanics, rehabilitation engineering and biomimetic robotics. In this paper, the various methods that have been used to synthesize human walking are reviewed from an engineering viewpoint. This involves a wide spectrum of approaches, from simple passive walking theories to large-scale computational models integrating the nervous, muscular and skeletal systems. These methods are roughly categorized under four headings: models inspired by the concept of a CPG (Central Pattern Generator), methods based on the principles of control engineering, predictive gait simulation using optimisation, and models inspired by passive walking theory. The shortcomings and advantages of these methods are examined, and future directions are discussed in the context of providing insights into the neural control objectives driving gait and improving the stability of the predicted gaits. Future advancements are likely to be motivated by improved understanding of neural control strategies and the subtle complexities of the musculoskeletal system during human locomotion. It is only a matter of time before predictive gait models become a practical and valuable tool in clinical diagnosis, rehabilitation engineering and robotics.

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CFD Validation of the Optimal Arrangement of the Propulsive Dorsal Fin of Gymnarchus niloticus

Hu Tian-jiang, Shen Lin-cheng, Gong Pei-ling

J4. 2006, 3 (3): 139-146. DOI:

Abstract ( 1349 )

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Gymnarchus niloticus, a typical freshwater fish, swims by undulations of a long-based dorsal fin aided by the two pectoral fins, while commonly it holds its body rigid and straight. The long flexible dorsal fin is the main propulsor of G. niloticus; it has also considerable influence on the streamline profile. This paper proposes a CFD approach to validate that the natural arrange-ment of the propulsive dorsal fin is optimal. Using morphological data and a smoothness-keeping algorithm, the dorsal fin is 'virtually' moved forward and backward with several displacements from the natural location. For each case, we reconstruct geometry, generate CFD grids, and calculate the pressure, viscous and total drag coefficients respectively. The results show that the pressure and total drag coefficients increase whether the dorsal fin is displaced forward or backward, and that greater dis-placement from its original position leads to greater pressure and total drag coefficients. This suggests that the natural position of the dorsal fin is significant for maintaining the fish’s streamline profile and reducing drag.

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CFD Simulation of Fish-like Body Moving in Viscous Liquid

D. Adkins, Y. Y. Yan

J4. 2006, 3 (3): 147-153. DOI:

Abstract ( 1311 )

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The study of fish-like bodies moving in liquid is an interesting and challenging research subject in the fields of bio-locomotion and biomimetics. Typically the effect of tail oscillation on fluid flow around such a body is highly unsteady, gen-erating vortices and requiring detailed analysis of fluid-structure interactions. An understanding of the complexities of such flows is of interest not only to biologists but also to engineers interested in developing vehicles capable of emulating the high per-formance of fish propulsion and manoeuvring. In the present study, a computational fluid dynamic (CFD) simulation of a three-dimensional biomimetic fish-like body has been developed to investigate the fluid flows around this body when moving in a viscous liquid. A parametric analysis of the variables that affect the flow surrounding the body is presented, along with flow visualisations, in an attempt to quantify and qualify the effect that these variables have on the performance of the body. The analysis provided by the unsteady transient simulation of a fish-like body has allowed the flow surrounding a fish-like body undergoing periodic oscillations to be studied. The simulation produces a motion of the tail in the (x, y) plane, with the tail os-cillating as a rigid body in the form of a sinusoidal wave.

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Design and Mechanics Simulation of Bionic Lubrication System of Artificial Joints

S. H. Su, Z. K. Hua, J. H. Zhang

J4. 2006, 3 (3): 155-160. DOI:

Abstract ( 1408 )

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We propose a new structure for artificial joints with a joint capsule which is designed to overcome the drawback of current prostheses that omit many functions of the lubricant and the joint capsule. The new structure is composed of three components: lubricant, artificial joint and artificial joint capsule. The lubricant sealed in the capsule can not only reduce the wear of the arti-ficial joint but also prevents the wear particles leaking into the body. So unexpected reactions between the wear particles and body can be avoided completely. A three-dimensional (3-D) finite element analysis (FEA) model was created for a bionic knee joint with capsule. The stresses and their distribution in the artificial capsule were simulated with different thickness, loadings, and flexion angles. The results show that the maximum stress occurs in the area between the artificial joint and the capsule. The effects of capsule thickness and the angles of flexion on stress are discussed in detail.

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Applications — Influence of Biology on Engineering

Julian F. V. Vincent

J4. 2006, 3 (3): 161-177. DOI:

Abstract ( 1155 )

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Examples are presented showing the way in which biological systems produce a range of functions which can be imple-mented in engineering, such as feedback-control of stiffness (muscles and nervous system), the design of fault-free structures (trees) and damage-tolerant materials (wood) and high performance insulation (penguin feathers) and shock absorbers (hedgehog spines).

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