Distributed control for synchronization of networked Lagrange systems via estimated state feedback

This paper investigates the synchronization control problem for a group of networked Lagrange systems without relative velocity measurements. Distributed observers are proposed to estimate the neighbors´ velocities. Based on the estimated states, the distributed controllers are designed to achieve the synchronization of the networked nonlinear systems. In contrast to other approaches, the development in this paper is suitable for the general directed communication topology, which is only required to have a spanning tree. Simulation examples are included to demonstrate the effectiveness of the proposed algorithms.