Passivity-based output synchronization of dynamical networks with non-identical nodes

Output synchronization of dynamical networks with non-identical nodes is studied using the passivity property. A synchronization criterion is developed for networks with general outer coupling topologies which need to be neither symmetric nor have the zero-row-sum property. When the passivity property cannot give synchronization for a single outer coupling topology, the problem of how to achieve synchronization by switching among several outer coupling topologies is studied. Synchronization conditions by switching among these topologies are presented and an output-dependent switching law is designed. In particular, it is shown that synchronizability can be checked by verifying if a certain nonlinear programming problem has no feasible solution or has a negative maximum.