A mixed-integer programming approach to networked control systems

This paper studies the problem of controller design for networked control systems regulated by a network data transmission protocol proposed in [50]. In this framework, the plant is first formulated as a mixed logical dynamical (MLD) system, then model predictive control (MPC) based on the mixed-integer programming is adopted to design a controller to guarantee certain control performance. It is shown that the solvability of the finite-horizon MPC is not equivalent to that of the infinite-horizon MPC, which is normally true for most existing MPC methods. The non-convexity feature of this type of networked control systems rules out explicit piecewise affine controllers that are designable for linear convex control systems. Notwithstanding these difficulties, controller design is still feasible due to the special nature of the data transmission strategy, i.e., only a small number of logic values are involved. Furthermore, control of higher-order systems and tracking of more complicated signals can be readily dealt with using this new approach. Two examples are presented to illustrate the strength of the proposed approach.