Coordinated trajectory tracking and collision-avoidance in dynamic environment for robots with double-integrated nonlinear dynamics

This paper aims to provide a low-level control strategy for a robot represented by a nonlinear second-order dynamics to avoid collision while tracking a specified trajectory in a dynamic environment and to extend it to coordinated trajectory tracking and collision-avoidance. Back-stepping technique has been exploited for trajectory tracking and collision-avoidance is performed by a repulsion function. A general form of repulsion function has been determined from Lyapunov stability theory. Using work and energy principle an upper bound for repulsion function under velocity saturation for both agents and obstacles is given which guarantees no collision occurrence. Since the assumption was that there are moving obstacles present in the environment, therefore, we may also assume each obstacle may be another robot following the same, or different path, thus coordinated tracking will be achieved.