Cushion Mechanism of Goat Hoof Bulb Tissues

Preparation and Application of Nature-inspired High-performance Mechanical Materials

Natural materials are valued for their lightweight properties, high strength, impact resistance, and fracture toughness, often outperforming human-made materials. This paper reviews recent research on biomimetic composites, focusing on how composition, microstructure, and interfacial characteristics affect mechanical properties like strength, stiffness, and toughness. It explores biological structures such as mollusk shells, bones, and insect exoskeletons that inspire lightweight designs, including honeycomb structures for weight reduction and impact resistance. The paper also discusses the flexibility and durability of fibrous materials like arachnid proteins and evaluates traditional and modern fabrication techniques, including machine learning. The development of superior, multifunctional, and eco-friendly materials will benefit transportation, mechanical engineering, architecture, and biomedicine, promoting sustainable materials science. STATEMENT OF SIGNIFICANCE: Natural materials excel in strength, lightweight, impact resistance, and fracture toughness. This review focuses on biomimetic composites inspired by nature, examining how composition, microstructure, and interfacial characteristics affect mechanical properties like strength, stiffness, and toughness. It analyzes biological structures such as shells, bones, and exoskeletons, emphasizing honeycomb strength and lightness. The review also explores the flexibility and durability of fibrous materials like arachnid proteins and discusses fabrication techniques for biomaterials. It highlights impact-resistant materials that combine soft and hard components for enhanced strength and toughness, as well as lightweight, wear-resistant biomimetic materials that respond uniquely to cyclic stress. The article aims to advance sustainable materials science by exploring innovations in multifunctional and eco-friendly materials for various applications.

Biomechanical functions analysis of the Mallard webbed foot: A study of macroscopic and microscopic material assembly and tendon morphology

The mallard webbed foot represents an exemplary model of biomechanical efficiency in avian locomotion. This study delves into the intricate material assembly and tendon morphology of the mallard webbed foot, employing both macroscopic and microscopic analyses. Through histological slices and scanning electron microscopy (SEM), we scrutinized the coupling assembly of rigid and flexible materials such as skin, tendon, and bone, while elucidating the biomechanical functions of tendons across various segments of the tarsometatarsophalangeal joint (TMTPJ). The histological examination unveiled a complex structural hierarchy extending from the external integument to the skeletal framework. Notably, the bone architecture, characterized by compact bone and honeycombed trabeculae, showcases a harmonious blend of strength and lightweight design. Tendons, traversing the phalangeal periphery, surrounded by elastic fibers, collagen fibers, and fat tissue. Fat chambers beneath the phalanx, filled with adipocytes, provide effective buffering, enabling the phalanx to withstand gravity, provide support, and facilitate locomotion. Furthermore, SEM analysis provided insights into the intricate morphology and arrangement of collagen fiber bundles within tendons. Flexor tendons in proximal and middle TMTPJ segments adopt a wavy-type, facilitating energy storage and release during weight-bearing activities. In contrast, distal TMTPJ flexor tendons assume a linear-type, emphasizing force transmission across phalangeal interfaces. Similarly, extensor tendons demonstrate segment-specific arrangements tailored to their respective biomechanical roles, with wavy-type in proximal and distal segments for energy modulation and linear-type in middle segments for enhanced force transmission and tear resistance. Overall, our findings offer a comprehensive understanding of the mallard webbed foot's biomechanical prowess, underscoring the symbiotic relationship between material composition, tendon morphology, and locomotor functionality. This study not only enriches our knowledge of avian biomechanics but also provides valuable insights for biomimetic design and tissue engineering endeavors.

Design of Bionic Foot Inspired by the Anti-Slip Cushioning Mechanism of Yak Feet

In recent years, legged robots have been more and more widely used on non-structured terrain, and their foot structure has an important impact on the robot's motion performance and stability. The structural characteristics of the yak foot sole with a high outer edge and low middle, which has excellent soil fixation ability and is an excellent bionic prototype, can improve the friction between the foot and the ground. At the same time, the foot hooves can effectively alleviate the larger impact load when contacting with the ground, which is an excellent anti-slip buffer mechanism. The bionic foot end design was carried out based on the morphology of the yak sole; the bionic foot design was carried out based on the biological anatomy observation of yak foot skeletal muscles. The virtual models of the bionic foot end and the bionic foot were established and simulated using Solidworks 2022 and Abaqus 2023, and the anti-slip performance on different ground surfaces and the influence of each parameter of the bionic foot on the cushioning effect were investigated. The results show that (1) the curved shape of the yak sole has a good anti-slip performance on both soil ground and rocky ground, and the anti-slip performance is better on soil ground; (2) the curved shape of the yak sole has a larger maximum static friction than the traditional foot, and the anti-slip performance is stronger under the same pressure conditions; (3) the finger pillow-hoof ball structure of the bionic foot has the greatest influence on the buffering effect, and the buffering effect of the bionic foot is best when the tip of the bionic foot touches the ground first.

From the Analysis of Anatomy and Locomotor Function of Biological Foot Systems to the Design of Bionic Foot: An Example of the Webbed Foot of the Mallard

This study utilized the mallard's foot as the subject, examining the bone distribution via computed tomography (CT) and analyzing pertinent parameters of the tarsometatarsal bones. Additionally, gross anatomy methods were employed to elucidate the characteristics of the toes and webbing bio-structures and their material composition. Biologically, the mallard's foot comprises tarsometatarsal bones and 10 phalanges, enveloped by fascia, tendons, and skin. Vernier calipers were used to measure the bones, followed by statistical analysis to acquire structural data. Tendons, originating in proximal muscles and terminating in distal bones beneath the fascia, facilitate force transmission and systematic movement of each segment's bones. Regarding material composition, the skin layer serves both encapsulation and wrapping functions. Fat pads, located on the metatarsal side of metatarsophalangeal joints and each phalanx, function as cushioning shock absorbers. The correlation between the force applied to the tarsometatarsal bones and the webbing opening angle was explored using a texture analyzer. A simplified model describing the driving force behind the webbing opening angle was introduced. Furthermore, we designed a bionic foot, contributing a foundational reference for anti-sinking bionic foot development.

Design of Bionic Buffering and Vibration Reduction Foot for Legged Robots

When legged robots walk on rugged roads, they would suffer from strong impact from the ground. The impact would cause the legged robots to vibrate, which would affect their normal operation. Therefore, it is necessary to take measures to absorb impact energy and reduce vibration. As an important part of a goat's foot, the hoof capsule can effectively buffer the impact from the ground in the goat's running and jumping. The structure of the hoof capsules and its principle of buffering and vibration reduction were studied. Inspired by the unique shape and internal structure of the hoof capsules, a bionic foot was designed. Experimental results displayed that the bionic foot could effectively use friction to consume impact energy and ensured the stability of legged robot walking. In addition, the bionic foot had a lower natural vibration frequency, which was beneficial to a wide range of vibration reduction. This work brings a new solution to the legged robot to deal with the ground impact, which helps it adapt to a variety of complex terrain.

The Passive Contact Stability of Blue Sheep Hoof Based on Structure, Mechanical Properties, and Surface Morphology

As the only component that contacts the ground and rock, the hooves of blue sheep may play a crucial role in their excellent climbing abilities. In this study, we used a combination of techniques, including scanning electron microscopy, infrared spectroscopy and nanoindentation, to characterize the surface morphology, structure, material composition, and mechanical properties of blue sheep hoof and investigate the potential contributions of these properties to the establishment of passive contact stability. Straight and curled microscopic lamellar morphology were found on the hoof surfaces. The cross section of the hoof revealed four layers, and each layer had a unique structure. Finite element analysis was employed to verify that the surface morphology and microstructure effectively contributed to the slip resistance and impact cushioning, respectively. Analyses of the energy and infrared spectra showed that the organic and inorganic substances in different regions of the hoof had similar components but different contents of those components. The hoof was mainly composed of keratin. From the outside to the inside, gradients in both the modulus and hardness were observed. These factors help the hoof alleviate high impact strengths and increase contact stability. These findings further our understanding of the unique mechanism of blue sheep hoof and may help in the development of novel biomimetic materials and mechanical components with enhanced friction and contact stability properties.