Cooperative output regulation for linear uncertain multi-agent systems with nonidentical relative degrees

In this paper, we study the cooperative robust output regulation problem of a class of heterogeneous minimum phase linear uncertain multi-agent systems with the arbitrary nonidentical relative degree via the output feedback control. We will propose a novel distributed observer to estimate the system state that contains two distinct parts, where the first part is of the distributed form to estimate the regulated error, while the second part is a modified version of the standard reduced order high gain observer by replacing the regulated error with its estimation given in the first part. Comparing with some current literatures, our design applies to a much larger class of linear multi-agent systems.