Showing papers by "Xian-Ming Zhang published in 2012"

Network-Based Filtering for Discrete-Time Systems

Abstract: This correspondence is concerned with network-based filtering for discrete-time systems. The output signals of the system under consideration are transmitted to the filter through a constraint communi- cation network, which usually leads to network-induced delays and packet dropouts. Byintroducinga logic datapacketprocessorto choose thenewest data signal from the network to actuate the filter, network-induced delays andpacketdropoutsaremodeledasaMarkovchaintakingvaluesinafinite set. As a result, the filter to be designed is modeled as a Markov jumping linear filter. By introducing some slack matrix variables in terms of prob- ability identity, a less conservative bounded real lemma (BRL) is derived to ensure that the filtering error system is stochastically stable with a pre- scribed level. Based on this BRL, suitable filters are designed by employing a cone complementary approach. A practical example on the Leslie model about some certain pest's structured population dynamics is given to show the effectiveness of the proposed approach.

On designing event-based H; ∞ filters for sampled-data systems

Abstract: This paper is concerned with the H; ∞ filtering for sampled-data systems. First, an event-based data packet processor is introduced to release the sampled measurement outputs only if an event condition is violated. As a result, the communication resources can be significantly saved while the desired system performance can be preserved. Second, the resulting filtering error system is modeled as an interval time delay system. By employing Lyapunov-Krasovskii functional method, a new bounded real lemma (BRL) is formulated such that the filtering error system can achieve a prescribed H; ∞ performance level. Third, by performing an invertible linear transformation on the filtering error system, the corresponding BRL to the transformed filtering error system is obtained, from which, suitable H; ∞ filters and the threshold parameter in the event condition can be co-designed provided that a set of linear matrix inequalities are feasible. Finally, the effectiveness of the proposed method is demonstrated through a mechanical system with two masses and two springs.

Active packet dropouts-based networked control system performance optimization

Abstract: This paper is concerned with active packet dropouts-based anti-disturbance performance optimization for a continuous-time networked control system (NCS) under consideration of time-varying network-induced delays. By proposing the active packet dropouts method, a new model for an NCS is established. Based on the established model, stabilizing controller design criteria are derived to optimize the anti-disturbance performance of the considered NCS. When transferring nonlinear matrix inequalities into linear matrix inequalities, a parameter searching algorithm and new bounding inequalities are proposed to introduce less conservatism. The mutually exclusive distribution characteristic of the interval time-varying delays is made full use to deal with integral inequalities for products of vectors. A numerical example is given to illustrate the effectiveness of the proposed active packet dropouts-based anti-disturbance performance optimization.

A novel stability criterion for networked control systems using a new bounding technique

Abstract: This paper is concerned with the stability of networked control systems in the discrete-time domain. A new bounding technique is proposed to estimate some finite-sum terms appearing in the forward difference of the chosen Lyapunov functional. This new bounding technique can provide tighter upper bounds for some finite-sum terms and avoid overly bounding for the finite-sum terms. Then a novel delay-dependent stability criterion is derived by using this new bounding technique. Compared with some existing stability criteria in the published literature, the novel stability criterion is proven theoretically to be less conservative and is shown to be of smaller numerical complexity.