Anti-saturation time-varying formation control via switching for a wider class of patterns of multiple uncertain marine surface vessels

This paper is devoted to the time-varying formation control of multiple marine surface vessels (MSVs) with input saturation. More serious uncertainties are involved than the related literature since external disturbance is considered while all the system parameters are unknown. Moreover, different from the severe constraints on the formation patterns and the leader’s dynamics in the related literature, rather fairly weak conditions are required since the relative deviations are only first but not more order continuously differentiable which imply that a wider class of formation patterns can be allowed, while the time derivatives of relative deviations as well as the leader’s output are not necessarily available for feedback. These two aspects make the traditional control methods on this topic ineffective. Then, by combining vectorial backstepping control method with logic-based switching mechanism, a switching controller is successfully designed for the formation control in this paper. It is worthwhile pointing out that, by the skilful design of a switching mechanism, the serious uncertainties are compensated while the severe assumptions on the formation patterns of the related literature are relaxed. Finally, simulation results are first provided to validate the effectiveness of the proposed theoretical results, and then a comparison with PID method is given to show the superiority of the proposed method.