Robust consensus tracking for heterogeneous linear multi-agent systems with disturbances

The robust consensus tracking problem is studied in this paper for a class of heterogeneous linear multi-agent systems with disturbances and directed communication topology graphs. A new kind of consensus protocol based on cooperative observers and relative states among neighbouring agents is first proposed. With the help of the designed cooperative observers, the agents in the group could reject the disturbances efficiently if at least one agent can measure the disturbances directly in a strongly connected graph. Furthermore, when the relative states between neighboring agents are unavailable, a distributed observer-type consensus tracking protocol based on relative output measurements is proposed. By using tools from Lyapunov stability theory, some sufficient criteria for achieving consensus tracking are obtained. Simulations are finally provided to illustrate the performance and effectiveness of the theoretical results.