Robust state agreement of nonlinear multi-agent systems with measurement and actuator disturbances

This article studies the robust state agreement problem for nonlinear multi-agent systems subject to measurement and actuator disturbances. Under a standard connectivity condition, it is shown that global robust agreement is achievable as long as the interaction functions between the multi-agent system satisfy a sector bound condition. In addition, a result on local robust state agreement is also given under a relaxed sector bound condition. An interesting lesson drawn from the study is that stronger interactions may destroy the robustness of global state agreement of nonlinear multi-agent systems with direct and switching topology.