Fuzzy-Based Sliding Mode Control and Sliding Mode Control of a Spherical Robot

Due to their complicated dynamics coupled with kinematics and non-holonomic underactuated behavior, spherical robots cannot unveil their full maneuverability when linear controllers are applied. Because of that, position and trajectory tracking of spherical robots have been the main challenges recently tackled in the literature. In this paper, two controllers are introduced to provide the effective path following of a 2-DOF spherical robot. A sliding mode controller (SMC) and a fuzzy sliding mode controller (FSMC) are designed and compared. The Lyapunov stability theorem is employed to analyze the stability of the controller and the tracking error. The simulation results indicate that the spherical robot controlled by the proposed methods is capable of moving to a desired point from any given initial point with minimum tracking error.