Analysis of Wireless Transmissions QoS relatively to the Dependability of a Networked Control System
Résumé
The interconnection of embedded and networked control system by wireless networks reclaims to take into account for the control of the system the Quality of Service provided by these networks. With the delay, packet losses inherent to wireless communications constitutes a challenging issue which required a global analysis. In this paper, the impacts of wireless transmissions are analyzed for an overhead travelling crane system. After an experimental study of the perturbing noise for the plant, a modification of TrueTime blocks is proposed, enabling the simulation of the whole process (environment, embedded system, network protocols, plant dynamics and control algorithms). It is next showed that the packet losses and the wireless packet retransmission protocol act together to the control of the system.