Design Of Bionic Foot Based On Biological Characteristics Of Yak Foot

There are abundant resources in the plateau environment,but the terrain is relatively complex,so it is far from enough to investigate and develop the resources by manpower alone.Compared with wheeled and tracked robots,legged robots can adapt to such relatively complex terrain better.As the part of the legged robot in direct contact with the ground,the structure and performance of the foot determine the stability and load capacity of the legged robot.Therefore,the research on the foot structure of legged robot has important practical significance.Despite their large size,yaks can move quickly and steadily in the complex environment of the plateau.This is due to the unique body structure of the yak and the excellent anti-slip cushioning performance of the feet.Taking yak foot as the research object,this paper studies the biological characteristics of yak foot and hoof.Combined with the movement characteristics of yak,this paper analyzes and summarizes the anti-skid cushioning mechanism of yak foot,establishes the biological model of yak foot,and designs the bionic foot,so as to provide theoretical basis and technical support for innovating the foot structure of foot robot and improving the anti-skid cushioning performance of the robot foot.The appearance and internal structure of yak feet were observed.The functions of different structures in the process of the movement were analyzed.Combined with yak sports video,the anti-skid cushioning mechanism of yak feet was summarized.The outer edge of the sole is high but the middle is low.This structure can fix the soil,improve the friction between the foot and the ground and play the role of anti-skid.The structure of Yak's foot is similar to that of ordinary cattle,but the tendon is thicker and the load is greater.The three main extensor tendons on the dorsal side control the dorsal flexion of the foot,and the three main flexor tendons on the palmar side control the flexion of the foot.When the foot moves,the toe touches the ground first,the tensioned flexor tendon plays a part of the cushioning role.After the full plantar landing,the metacarpal bone compresses the mesentery and crown bone,and the crown bone compresses the sesamoid bone to exert force on the elastic finger pillow and ungula sphere.The cushion effect is achieved through the deformation of the finger pillow and ungula sphere.The characteristic parts of the yak capsula ungula were observed by scanning electron microscope.The ungula wall was hard and had a protective effect;The ungula sphere has an obvious layered structure.The surface layer in contact with the ground is densely arranged and has good wear resistance.The inner layer has a hole structure.It can be buffered by compressing the hole after compression.After deformation,it can increase the contact area of the ground and improve the anti-skid performance.The three-dimensional model of the yak foot is reconstructed by reverse engineering technology,and the mathematical model of the foot surface is extracted and constructed.Based on medical imaging technology and reverse engineering software,the shape model of the yak foot skeleton and hoof was reconstructed.The surface of the reconstructed model is smooth and has the characteristics of the yak foot.The anti-slip performance of yak sole was studied based on the reconstructed yak hoof model.The anti-slip performance of special surface of yak sole was simulated and analyzed by finite element analysis method.The anti-slip performance of yak foot on different ground was studied.Compared with the traditional foot,the yak foot has good anti-slip performance.Taking yak foot as the bionic prototype,a bionic foot was designed according to its structure and motion characteristics,and a three-dimensional model was established to carry out dynamic simulation analysis to study its cushioning performance.An orthogonal test design was adopted to explore the impact of parameters of the bionic foot on cushioning effect.The results show that the finger-pillow-ungula-sphere structure of the bionic foot has the greatest impact on the cushioning effect,and the cushioning effect of the bionic foot is the best when the toe of the bionic foot touches the ground first,which is consistent with the actual cushioning mechanism of the yak foot.