Consensus Problems for Networked Uncertain Euler-Lagrange Systems Subject to Communication Delays

Abstract

In this paper, consensus problems are addressed for networked Euler-Lagrange systems (EL-systems) subject to parameters uncertainties and non-uniform communication delays. A modified distributed consensus algorithm with damping terms is proposed, and more general sufficient consensus conditions that are independent of the communication delays are obtained. Furthermore, the necessary and sufficient consensus conditions are derived if the communication delays are less than certain upper bound, which together with the general sufficient conditions, yields less conservative results for selecting consensus control parameters. With frequency domain analysis, input-output property and the final value theorem, we show that the proposed distributed consensus algorithm ensures the convergence of ultimate positions of all EL-systems to an agree value, and enables the explicit dependency of the agree value on an independent control parameter. By setting the parameter properly, the desired consensus states of all EL-systems can be reached. Numerical simulations are shown to verify the effectiveness of the analytical results.