A Novel Serpentine Gait Generation Method for Snakelike Robots Based on Geometry Mechanics

In this paper, a novel serpentine gait generation method is proposed based on geometry mechanics. From the view of differential geometry, the configuration of snake-like robots can be described by a fiber bundle, in which the net locomotion corresponds to the fiber space and the gait corresponds to the bases space. The serpentine gait can be generated by calculating the connection of the fiber bundle. Compared with the traditional gait generation method, such as the curve-based method and the central pattern generator-based method, the proposed method does not assume that the serpentine gait is a standard sinusoidal signal. Models have been developed based on geometric mechanics, which build the relation between the net locomotion and the serpentine gaits analytically. Based on these models, the serpentine gaits for snakelike robots with passive wheels can be generated by planning the quasi-velocity and the serpentine gaits for underwater snakelike robots can be generated by analyzing the integral of the height function. The serpentine gaits generated by the proposed method directly couple with the locomotion of the snakelike robot, which enables the desired locomotion to be realized efficiently. To validate the proposed method, both the snakelike robot with passive wheels and the underwater snakelike robot are taken to perform the experiments. Additionally the recursive Newton-Euler method with the model of hydrodynamic forces is also taken to test the underwater serpentine gaits. Experiments and simulation have validated our proposed method.