Event-triggered robust model predictive control for Lipschitz nonlinear networked control systems subject to communication delays

Abstract

In this paper, the problem of event-triggered robust model predictive control (MPC) was examined for a class of Lipchitz nonlinear networked control systems (NCS) with network-induced delays and subject to external disturbances. An event-triggering scheme for a continuous-time NCS was proposed, which reduced the communication traffic and computational burden of the MPC algorithm simultaneously. In comparison with the existing event-triggered nonlinear MPC (NMPC) approaches, the controller in this paper was designed as a state feedback control law, which minimized a “worst-case” performance index over an infinite horizon subject to constraints on the control input. The controller and event generator parameters were developed as a convex optimization problem, encompassing some linear matrix inequalities (LMIs). Simulation results showed that the proposed event-triggering NMPC scheme preserved closed-loop performance while reducing the communication rate and the computational time.

Decentralized event‐triggered robust MPC for large‐scale networked Lipchitz non‐linear control systems

“…Nevertheless, it deserves further study. Remark In our former study [39], the integral inequality lemma for matrix cross‐products [48] played a key role to relax the integral terms of quadratic quantities and obtain stability criteria for the closed‐loop delayed system. Besides, we introduced slightly excessive free weighting matrices which significantly increased the number of decision variables.…”

“…Similar to the presented approach in [39], at sampling time t i k h, we assume that the bound on Euclidean norm of the control input is equal to…”

“…We developed a method [39] ensuring the asymptotic stability of a single Lipschitz non-linear closed-loop system within the context of NCS. Thus, it can use the technique in [39] to design decentralized event-triggers MPC in inter-connected network control systems and assign effectively network resources within the coupled subsystems.…”

Event‐triggered MPC for linear systems with bounded disturbances: An accumulated error based approach

“…Robust constraint satisfaction was achieved by computing time‐varying tightened state constraint, and event‐triggered scheduling scheme was established in a dual‐mode MPC framework. The event‐triggered robust MPC technique for a kind of Lipschitz nonlinear system with network‐induced time‐lag and external disturbances was studied in [25]. In [26], for robust constrained MPC systems, a new event‐triggered scheme on the basis of indenture invariant set trajectory of robust control was proposed, in which triggering condition is depended on the relevance between two continuous state vector sets.…”

“…Therefore, it is desired that MPC be combined with eventtriggering strategy to save communication resources and online computing resources. There are many research results related to event-triggered MPC (ET-MPC), mainly divided into two categories, that is, ET-MPC for linear systems [13][14][15][16][17][18] and for nonlinear systems [19][20][21][22][23][24][25]. More specially, in [13], for discrete-time linear systems with constraints and external disturbances, an ET-MPC method was proposed.…”