Dynamic modeling and simulation of a snake-like multibody robotic system with ground-adaptive strategy and efficient undulatory locomotion

This article presents a strategy of self adaptation for planar undulatory locomotion of an elongated, snake-like multibody robotic system under both non-varying and varying surface friction. Based on the system dynamics, an algorithm is developed to investigate the locomotion performance and its dependence upon the lateral undulation parameters. The celerity of the lateral undulatory wave propagating over the body of the robot is taken as a key parameter, since the variation of the celerity affects the forward propulsion speed of the robot. Moreover, celerity of the lateral undulatory wave is a linear function of the angular frequency of the sinusoidal motion imposed on the joints of the robot. Considering the static-kinetic lateral friction, the proposed algorithm computes the important point of separation between no-lateral slip and lateral slip simply with the help of celerity and speed of propulsion. Therefore, the results identify the optimum speed of propulsion for ground-adaptivity and efficient undulatory locomotion of the robot. The simulation results further verify the influence of the angular frequency of the sinusoidal joint motion upon the speed of propagation of the undulatory wave and also upon the speed of propulsion of the robot. This research work can provide useful basis for the control, optimization and self-adaptive locomotion of such and similar robots.