Guaranteed Cost Control for Uncertain Networked Control Systems With Predictive Scheme

The problem of guaranteed cost control for a class of networked control systems possessing uncertainties, network delays, and packet dropouts is solved in this paper. By means of introducing an auxiliary variable, a newly coupled, switched system model is derived first. Then, based on a predictive network control scheme, the conditions for guaranteed control performance of the overall system in terms of linear matrix inequalities are given. Next, a novel control design method, involving convex optimization technique to find solutions for the controllers that vary according to network delays and data-dropouts, is developed. It is shown from theory that the obtained criteria are much less conservative than existing ones. Finally, two illustrative examples, the second one being a laboratory-scale rig, are elaborated on to demonstrate the effectiveness of the proposed design method. Both numerical and simulation results appear favorable to this novel network control system synthesis. Note to Practitioners-This paper is motivated by the problem of compensating the time-varying delays and data dropouts in networked control systems (NCSs). Overcoming the effects of time-varying delays and data dropouts in NCSs is an important issue, especially in industrial operations where the control signals are transmitted through the internet. In this paper, a novelmodel is established to capture the relationship of delays between the consecutive sampling points. The predictive scheme is used to compensate the effects of the network delays and data dropouts in NCSs. Simultaneously, it is more meaningful from the view of engineering to guarantee that the systems possess strong robust performance except for system stability. In this paper, we not only provide the stability analysis for the considered system but also give a controller design scheme to compensate the disadvantages of the time-varying delays and data dropouts such that the NCSs satisfy a performance index. The proposed control method is finally used to control a DC-motor through the Intranet, of which the aim is to obtain a desired speed. The method is shown valid and less conservative compared with other existing ones.