Kinematic modeling of a bio-inspired robotic fish

This paper proposes a kinematic modeling method for a bio-inspired robotic fish based on single joint. Lagrangian function of freely swimming robotic fish is built based on a simplified geometric model. In order to build the kinematic model, the fluid force acting on the robotic fish is divided into three parts: the pressure on links, the approach stream pressure and the frictional force. By solving Lagrange's equation of the second kind and the fluid force, the movement of robotic fish is obtained. The robotic fish's motion, such as propelling and turning are simulated, and experiments are taken to verify the model.

Review of trust and machine ethics research: towards a bio-inspired computational model of ethical trust (CMET)

Recent advances in the fields of robotics, cyborg development, moral psychology, trust, multi agent-based systems and socionics have raised the need for a better understanding of ethics, moral reasoning, judgment and decision-making within the system of man and machines. Here we seek to understand key research questions concerning the interplay of ethical trust at the individual level and the social moral norms at the collective end. We review salient works in the fields of trust and machine ethics research, underscore the importance and the need for a deeper understanding of ethical trust at the individual level and the development of collective social moral norms. Drawing upon the recent findings from neural sciences on mirror-neuron system (MNS) and social cognition, we present a bio-inspired Computational Model of Ethical Trust (CMET) to allow investigations of the interplay of ethical trust and social moral norms.

Ethical trust and social moral norms simulation : a bio-inspired agent-based modelling approach

The understanding of the micro-macro link is an urgent need in the study of social systems. The complex adaptive nature of social systems adds to the challenges of understanding social interactions and system feedback and presents substantial scope and potential for extending the frontiers of computer-based research tools such as simulations and agent-based technologies. In this project, we seek to understand key research questions concerning the interplay of ethical trust at the individual level and the development of collective social moral norms as representative sample of the bigger micro-macro link of social systems. We outline our computational model of ethical trust (CMET) informed by research findings from trust, machine ethics and neural science. Guided by the CMET architecture, we discuss key implementation ideas for the simulations of ethical trust and social moral norms.

Bio-inspired nanotechnology: from surface analysis to applications

This book focuses on the use of bio-inspired and biomimetic methods for the fabrication and activation of nanomaterials. This includes studies concerning the binding of the biomolecules to the surface of inorganic structures, structure/function relationships of the final materials and extensive discussions on the final applications of such biomimetic materials in unique applications including energy harvesting/storage, biomedical diagnostics and materials assembly.

Bio-inspired hydrogen-bond cross-link strategy toward strong and tough polymeric materials

It remains a huge challenge to create advanced polymeric materials combining high strength, great toughness, and biodegradability so far. Despite enhanced strength and stiffness, biomimetic materials and polymer nanocomposites suffer notably reduced extensibility and toughness when compared to polymer bulk. Silk displays superior strength and toughness via hydrogen bonds (H-bonds) assembly, while cuticles of mussels gain high hardness and toughness via metal complexation cross-linking. Here, we propose a H-bonds cross-linking strategy that can simultaneously strikingly enhance strength, modulus, toughness, and hardness relative to polymer bulk. The H-bond cross-linked poly(vinyl alcohol) exhibits high yield strength (140 MPa), reduced modulus (22.5 GPa) in nanoindention tests, hardness (0.5 GPa), and great extensibility (40%). More importantly, there exist semiquantitive linear relationships between the number of effective H-bond and macroscale properties. This work suggests a promising methodology of designing advanced materials with exceptional mechanical by adding low amounts (1.0 wt %) of small molecules multiamines serving as H-bond cross-linkers.

A biomechanically optimized knitted stent using a bio-inspired design approach

Vascular implants have always been a key area of research in medical textiles. Knitted structures have been proven to be suitable for stent applications on the basis of their looped mesh geometry, structural flexibility and ease of manufacturing. However, there are biomechanical constraints of plain knit constructions that can result in clinical complications after implantation and hence cannot be ignored. This study reports a new segmented knit design inspired by structural metamerism observed in the body design of some invertebrate animals. Metamerism is the phenomenon of having a linear series of body segments fundamentally similar in structure, but assigned to perform different functions. It was hypothesized that utilization of this simple and yet effective biological design approach in stent construction could improve the degree of control for optimizing stent biomechanical properties. The proposed segmented stent was constructed by incorporating an elastic filament component into a polyethylene terephthalate knitted stent at specific intervals along its length, also known as the ‘Plating Technique’. This technique generates a structure with alternately arranged stiff and elastic knitted sections which equip the stent with vital structural support and volumetric compliance properties, respectively. The stent design parameters (filament diameter, loop length, segmentation plan) were optimized to achieve significantly better biomechanical performance (bending flexibility, compression resistance, volumetric expansion, longitudinal extensibility) than a plain knit stent.

PhysarumSpreader: a new bio-Inspired methodology for identifying influential spreaders in complex networks

Identifying influential spreaders in networks, which contributes to optimizing the use of available resources and efficient spreading of information, is of great theoretical significance and practical value. A random-walk-based algorithm LeaderRank has been shown as an effective and efficient method in recognizing leaders in social network, which even outperforms the well-known PageRank method. As LeaderRank is initially developed for binary directed networks, further extensions should be studied in weighted networks. In this paper, a generalized algorithm PhysarumSpreader is proposed by combining LeaderRank with a positive feedback mechanism inspired from an amoeboid organism called Physarum Polycephalum. By taking edge weights into consideration and adding the positive feedback mechanism, PhysarumSpreader is applicable in both directed and undirected networks with weights. By taking two real networks for examples, the effectiveness of the proposed method is demonstrated by comparing with other standard centrality measures.

Design and properties of a new hybrid stent-graft device

This PhD work explored a novel bio-inspired approach for designing artificial blood vessel implants known as stent-grafts. The design was inspired from body design of a caterpillar. This design concept induced natural flexibility and expandability property in the new stent-graft, which is considered critical in deciding long-term health of treated patients.

Lessons from silkworm cocoons for future protective materials design

 Evolved over millions of years’ natural selection, very thin and lightweight wild silkworm cocoons can protect silkworms from environmental hazards and physical attacks from predators while supporting their metabolic activity. The knowledge of structure-property-function relationship of multi-layered composite silk cocoon shells gives insight into the design of next-generation protection materials. The mechanical and thermal insulation properties of both domestic (Bombyx mori, or B. moriand Samia. cynthia, or S. cynthia) and wild (Antheraea pernyi and Antheraea mylitta, or A. pernyi and A. mylitta) silkworm cocoons were investigated. The research findings are of relevance to the bio-inspired design of new protective materials and structures.
The 180 degree peel tests and needle penetration tests were used for examining the peel resistance and needle penetration resistance of both domestic and wild silkworm cocoon walls. The temperatures inside and outside of the whole silkworm cocoons under warm, cold and windy conditions were monitored for investigating the cocoon’s thermal insulation function. Computational fluid dynamics (CFD) models were created to simulate the heat transfer through the A. pernyi cocoon wall.
The wild cocoons experienced much higher peeling peak loads than the domestic cocoon. This transfers to a maximum work-of-fracture (WOF) of about 1000 J/m2 from the A. pernyi outer layer, which was 10 times of the B. mori cocoon. The A. pernyi wild cocoon exhibited a maximum penetration force (11 N) that is 70 % higher than a woven aramid fabric. Silk sericin is shown to play a critical role in providing needle penetration resistance of the non-woven composite cocoon structure by restricting the relative motion of fibres, which prevents the sharp tip of the needle from pushing aside fibres and penetrating between them. The wild A. pernyi cocoon exhibits superior thermal buffer over the domestic B. mori cocoon. The unique structure of the A. pernyi cocoon wall with mineral crystals deposited on the cocoon outer surface, can prohibit most of the air from flowing inside of the cocoon structure, which shows strong wind resistance under windy conditions.

An amoeboid algorithm for solving linear transportation problem

Transportation Problem (TP) is one of the basic operational research problems, which plays an important role in many practical applications. In this paper, a bio-inspired mathematical model is proposed to handle the Linear Transportation Problem (LTP) in directed networks by modifying the original amoeba model Physarum Solver. Several examples are used to prove that the provided model can effectively solve Balanced Transportation Problem (BTP), Unbalanced Transportation Problem (UTP), especially the Generalized Transportation Problem (GTP), in a nondiscrete way. © 2013 Elsevier B.V. All rights reserved.

Crack damage in polymers and composites: a review

Polymer-based materials are extensively used in various applications such as aircrafts, civilian structures, oil and gas platforms and electronics. They are, however, inherently damage prone and over time, the formation of cracks and microscopic damages influences the thermo-mechanical and electrical properties, which eventually results in the total failure of the materials. This paper provides an overview of the principal causes of cracking in polymer and composites and summarizes the recent progress in the development of non-destructive techniques in crack detection. Furthermore, recent progress in the development of bio-inspired self-healing methods in autonomic repair is discussed.