Trajectory Tracking Control of Snake Robots Based on Dynamic Model

In this paper, we derive a dynamic model and a trajectory tracking control law for snake robots, which have passive wheels and active joints, based on the dynamic model. For a trajectory tracking control of snake robots, it is one of the important problem to avoid the singular configuration like a straight line. Using input-ouput linearization for the head position of snake robots based on dynamic model, we can control the head position by PD feedback, but the robot will converge to the singular configuration. In order to solve this problem, we propose a control law that controls shape controllable points for avoiding the singular configuration. Using the proposed control law, the robot can accomplish trajectory tracking of the head position without converging to the singular configuration. Simulation results show the effectiveness of the proposed control law.