Stabilizing MPC for network-controlled systems with an application to DC motors

In this paper the problem of time-varying network induced delay in industrial applications, such as remote DC motor speed control, is addressed. The goal of this paper is to provide a control design methodology that can assure the closed-loop performances of the industrial application, in a tele-operation environment, while compensating the time-varying delays introduced by the communication network. To this end, firstly, the error caused by the time delay is considered as a disturbance and a novel method of finding the bounds of the disturbance is proposed. Secondly, an one step ahead predictive controller based on flexible control Lyapunov functions is designed, which explicitly takes into account the bounds of the disturbances caused by the time-varying network-induced delay and guarantees also the input-to-state stability of the system. The methodology is then applied for a network-controlled DC motor to illustrate the effectiveness and robustness of the proposed delay modeling and control strategy.