Fatigue Analysis of Leg Structure of a Natatores-Like Amphibious Robot

With the increasing demand for ocean exploration and development, the research about the amphibious robot is of great significance. In this paper, a natatores-like amphibious robot was designed by using the driving method of paddling by webbed foot. This mode has the advantages of high propulsion efficiency, good mobility and good stability. Due to the characteristics of this propulsion mode, the leg structure of the robot is often applied with periodic loads. And therefore it is necessary to verify the mechanical performance of the leg structure. The elastoplastic finite element model of the leg structure of the robot was modelled, and the fatigue analysis of the model under the walking gait were carried out. The results showed that the fatigue failure of the thigh and the shank would not occur within the design life, which met the design requirements. The analysis results can provide reference for the material selection and structural optimization design of leg in the subsequent work.