Consensus disturbance rejection of network-connected dynamic systems with input delay and unknown network connectivity

In this paper, we consider the distributed consensus problem for multi-agent systems with input delay and unknown disturbances. To deal with the input delay and disturbances, a predictor- and disturbance observer-based control strategy is developed for each follower. Then, a distributed robust adaptive consensus protocol with dynamic coupling gains is proposed based on the relative state of the neighbouring agents, guaranteeing that all signals in the closed-loop dynamics are uniformly ultimately bounded and the consensus tracking error converges to an arbitrarily small residual set. The controllers are proposed in a fully distributed way such that the global information related to the eigenvalues of the Laplacian matrix is not needed. Finally, the validity of the proposed controller is demonstrated through a numerical example.