Distributed H∞ optimal control of networked uncertain nonlinear Euler-Lagrange systems with switching communication network topologies

This paper is concerned with the design of distributed state synchronization and trajectory tracking control laws for nonlinear Euler-Lagrange (EL) systems in presence of parameter uncertainty and external disturbances with fixed and switching communication network topologies. Specifically, H∞ optimal control techniques are employed to formally design controllers which address the state synchronization and trajectory tracking of a team of multi-agent nonlinear EL systems while the agents have access to only local information. It is shown that the state synchronization (or consensus) protocol and trajectory tracking controllers can be formally derived by employing our proposed analysis. In addition, we formally show that our proposed distributed state synchronization and tracking control algorithms for EL systems is input-to-state stable (ISS) where the input is taken as parameter uncertainty as well as external disturbances. Our results are obtained for both fixed and switching communication network topologies. Simulation results for attitude control of a network of spacecraft demonstrate the effectiveness and capabilities of our proposed distributed control algorithms.