Target Enclosing and Trajectory Tracking for a Mobile Robot With Input Disturbances

This letter investigates two control problems of a unicycle-type mobile robot: 1) target enclosing and 2) trajectory tracking. The existence of disturbance in velocities, i.e., the input channels of a mobile robot, is considered in both problems. The input disturbance is assumed to be generated by a linear exogenous system, which can be used to describe linear combinations of a finite number of sinusoidal signals and step signals. Two dynamic control laws are proposed respectively, such that the disturbance rejection is achieved and global asymptotic stability of the closed-loop system is guaranteed. Finally, simulation results of an example verify effectiveness of the proposed control laws.