Robust distributed consensus tracking control for high-order uncertain nonlinear MASs with directed topologies

This paper addresses the robust distributed consensus tracking problem for leader-follower multi-agent systems (MASs) with nonlinear dynamics and external disturbances under directed graph topologies. The nonlinear uncertainties are not required to be continuous or meet the matching conditions. The backstepping design method combined with signal compensation approach is proposed to design robust controllers in order to guarantee the consensus tracking property between the followers and the one leader. Moreover, the dynamic surface control technique is used to deal with the 'explosion of complexity' problem. It is proven that the robust distributed consensus tracking property of the MASs can be guaranteed. Furthermore, the consensus tracking errors can be designed as small as required and the convergence speed can be chosen arbitrarily. Finally, two examples are presented to show the validity of the proposed consensus tracking control protocols.