Kinematics and Dynamics of a Snake Robot with Worm Like Locomotion on Inclined Surface

Snake robots are hyper-redundant robots that are connected with one or two DOF joints. They offer a number of potential advantages beyond the capabilities of most wheeled and legged robots. In this paper، kinematics and dynamics of a planar multi-link snake robot in worm-like locomotion on an inclined surface is investigated. In this locomotion، Snake robot is able to move in the vertical plane. Body shape and curvature function are used to determine the joint relative angles in accordance with the worm-like locomotion. Next، position، velocity and acceleration of each link as well as center of gravity of the snake body are calculated. Newton principle is used to derive the dynamic equations based on kinematics of the snake robot. Friction forces، as the only driving force is modeled using Coulomb friction. Effects of friction coefficient and angle of inclined surface on the joint torques are investigated. It is shown that by increasing these coefficients the motor torques also increase. Webots software and Lagrangian method are both used to verify the theoretical results. Additionally، kinematics and dynamics equation presented in this paper may be used to generate other locomotions in vertical plane. Effect of link geometrical shape on motor torques is also investigated. Finally، FUM-Snake3 robot and physical experiments are used to further validate the mathematical model.