A modular amphibious snake-like robot: Design, modeling and simulation

Snake-like robots are a class of hyper-redundant bionic robots. They have small cross-section and many degrees of freedom (DOFs), making them ideally suited to travel on confined spaces such as underwater caves, sunken vessels, collapsed buildings, and so on. Especially, an amphibious snake-like robot can move both on ground and underwater. In this paper, we proposed a kind of amphibious snake robot with modularized joints, controllers, and structures. It can perform tasks such as maritime accident rescue, amphibious environment detection, emergency response and life rescue, meeting the requirement on many fields. This robot is composed by 10 modularized joints with new structure. Each joint has 2 DOFs (pitch and yaw), which make the robot locomote in three-dimensional agilely. All the revolute joints are arranged in the configuration of Pitch-Yaw-Pitch-Yaw (abbreviated as PYPY structure). With this configuration, the robot has very dexterous movement ability. Then, we derived the analytical kinematics equations, based on which we planned the typical gait for it. At last, the dynamic model including the ground and aquatic environment was created by using Webots. The simulation study on typical cases was performed and the simulation results verified the mechanical design, kinematics and gait planning of the robotic system.