On interplays between the Quality of Service and the Quality of Control for a co-design approach in a Wireless Networked Control System (WNCS)

International audienceWe consider the implementation of process control applications on a Wireless LAN with a collision-free CSMA MAC protocol called CANlike (adaptation of the MAC protocol of the CAN bus to the wireless context). The goal of this paper is to show a co-design approach which is based on relations between the Quality of Control (QoC) provided by the controller and the Quality of Service (QoS) provided by the frame scheduling in the MAC layer of the Wireless LAN. We present, first, the relation QoS-->QoC on the basis of a compensation method for time delays called dominant pole method, and second, the relation QoC-->QoS based on the hybrid priorities for the frame scheduling. Finally, we show the interest of the joint action of the delay compensation and the role of the hybrid priority (i.e. relation QoSQoC) in order to have a more efficient Wireless NCS design