Networked Control under Time-Synchronization Errors

This work concerns the observer-based control of a remote, master-slave system through the Internet network. This communication link introduces variable, asymmetric and unpredictable delays. The data-sampling effects are also taken into account, even in the aperiodic case. Previous strategies were requiring additional buffers, allowing the delay to become constant but greater and that the slave and the master share the same clock. In this article, these assumptions are not longer required. Thanks to an adequate Lyapunov-Krasovskii functional, the present result uses the information as soon as received. The proposed LMI ensure the asymptotic stability of the global closed loop system. The maximum admissive synchronization error is also computed. The last part of the paper provides an example where the slave is a second-order system.