Output synchronization of networked passive systems

In this thesis we study the problem of output synchronization for a class of multi-input/multi-output nonlinear networked systems (agents, for short) whose dynamics are input-output passive. The agents are said to output synchronize if their outputs are asymptotically pairwise convergent.;The agents exchange information over a network whose topology is described by an interconnection graph. We present synchronization results for both fixed and arbitrarily switching graphs. We treat both linear interconnections on balanced, directed graphs and nonlinear interconnections on undirected graphs. We also treat the realistic case of time delay in the communication of information among agents. We show that the passivity assumption allows synchronization for arbitrary constant (bounded) time delays in communication. Our results unify several existing results from the literature on multi-agent systems.;We next apply our results to the problem of synchronization of Kuramoto oscillators. The traditional Kuramoto model, which consists of N oscillators with possibly distinct natural frequencies and all-to-all connectivity, is said to synchronize if the angular frequencies of all oscillators converge to the mean natural frequency of the group. Our main result demonstrates exponential oscillator synchronization to the mean frequency in the Kuramoto model with distinct natural frequencies.;Our results are also used to address the general problem of synchronization of multiple Lagrangian systems. The problems of multi-robot coordination and of bilateral teleoperation with time delay are shown to be special cases of our general results.