Qingshuang Zeng

Observer-based sliding mode control for a class of uncertain nonlinear neutral delay systems

In this paper, the observer-based sliding mode control (SMC) problem is investigated for a class of uncertain nonlinear neutral delay systems. A new robust stability condition is proposed first for the sliding mode dynamics, then a sliding mode observer is designed, based on which an observer-based controller is synthesized by using the SMC theory combined with the reaching law technique. Then, a sufficient condition of the asymptotic stability is proposed in terms of linear matrix inequality (LMI) for the overall closed-loop system composed of the observer dynamics and the state estimation error dynamics. Furthermore, the reachability problem is also discussed. It is shown that the proposed SMC scheme guarantees the reachability of the sliding surfaces defined in both the state estimate space and the state estimation error space, respectively. Finally, a numerical example is given to illustrate the feasibility of the proposed design scheme.

New robust delay-dependent stability and H∞ analysis for uncertain Markovian jump systems with time-varying delays

This paper deals with the problems of robust delay-dependent stability and H∞ analysis for Markovian jump linear systems with norm-bounded parameter uncertainties and time-varying delays. In terms of linear matrix inequalities, an improved delay-range-dependent stability condition for Markovian jump systems is proposed by constructing a novel Lyapunov–Krasovskii functional with the idea of partitioning the time delay, and a sufficient condition is derived from the H∞ performance. Numerical examples are provided to demonstrate efficiency and reduced conservatism of the results in this paper.

Sliding mode control of T–S fuzzy descriptor systems with time-delay ☆

Abstract This paper is concerned with the problem of sliding mode control (SMC) of a class of Takagi–Sugeno (T–S) fuzzy descriptor system with time-delay. An integral-type sliding surface function is designed by taking the descriptor matrix into account, thus the resulting sliding mode dynamics is a full-order uncertain T–S fuzzy descriptor time-delay system. By the use of the delay partitioning technique, a delay-dependent criterion is established, which ensures the sliding mode dynamics to be regular, impulse-free and stable. Moreover, an SMC law is synthesized to guarantee the stability of the closed-loop system, and the proposed SMC law can drive the dynamics of controlled system into a designated sliding surface in finite time. Finally, a numerical example is provided to illustrate the effectiveness of the proposed theories.

Nonfragile Control With Guaranteed Cost of T–S Fuzzy Singular Systems Based on Parallel Distributed Compensation

This paper investigates the nonfragile-guaranteed cost control problem for a class of uncertain nonlinear singular state-delayed systems that is described by Takagi-Sugeno models. The upper bound of state delay is assumed to be available. A linear quadratic cost function is specified as the performance index of the closed-loop system. Attention is focused on the fuzzy state feedback controller design via parallel distributed compensation scheme, which not only guarantees the regular, impulse-free, and asymptotically stable of the closed-loop fuzzy singular delay system, but also provides an optimized upper bound of the guaranteed cost function for the possibility of feedback gain variation and all admissible uncertainties. All derived sufficient conditions are given in terms of linear matrix inequalities. Some numerical examples are provided to illustrate the effectiveness of the proposed design scheme.

Consensus of Euler–Lagrange Systems Networked by Sampled-Data Information with Probabilistic Time Delays

This paper investigates the consensus problem of multiple Euler-Lagrange systems under directed topology. Unlike the common assumptions on continuous-time information exchanges, a more realistic sampled-data communication strategy is proposed with probabilistic occurrence of time-varying delays. Both of the sampling period and the delays are assumed to be time-varying, which is more general in some practical situations. In addition, the relative coordinate derivative information is not required in the distributed controllers such that the communication network burden can be further reduced. In particular, a distinct feature of the proposed scheme lies in the fact that it can effectively reduce the energy consumption. By employing the stochastic analysis techniques, sufficient conditions are established to guarantee that the consensus can be achieved. Finally, a numerical example is provided to illustrate the applicability and benefits of the theoretical results.

On dissipativity of Takagi–Sugeno fuzzy descriptor systems with time-delay

Abstract This paper is concerned with the dissipativity analysis for Takagi–Sugeno (T–S) fuzzy descriptor systems with time-delay. By using of delay partitioning approach, a delay-dependent criterion is established in terms of strict linear matrix inequalities (LMIs), which guarantees the considered system to be admissibility and strict ( Q , R , S ) - α -dissipativity. The obtained results dependent upon not only time delay but also the number of delay partitions, thus are less conservative. In addition, the developed results encompass available results on H ∞ performance and strict passivity analysis as special cases. A numerical example is provided to illustrate the effectiveness of the proposed theories.

Distributed formation control of 6-DOF autonomous underwater vehicles networked by sampled-data information under directed topology

In this paper, a sampled-data networking strategy is investigated for the formation problem of multiple 6-DOF autonomous underwater vehicles (AUVs) in the presence of external disturbances. Unlike the common condition in most literatures associated with multiple vehicles, where the information is assumed to be exchanged continuously, in our proposed strategy, the position and orientation information of the multiple AUVs is exchanged according to a discrete-time sequence, which is more applicable to current technologies for underwater communications. More precisely, this strategy can be modeled by a sample-and-hold mechanism and is capable of both uniform and non-uniform sampling cases. In particular, it has a potential advantage from an energy perspective, since communication reduction always leads to less energy consumption. By model transformation, distributed controllers are designed based on input-to-state stability (ISS) property to ensure that both configuration formation and rendezvous-type formation can be achieved. An optimization procedure is also presented to calculate the maximum allowable sampling period. Finally, a numerical example is provided to illustrate the effectiveness and applicability of the theoretical results.

Distributed adaptive attitude synchronization for spacecraft formation flying with sampled-data information flows

Abstract This paper investigates the adaptive attitude synchronization problem of spacecraft formation flying in the presence of unknown parameters and external disturbances. Specifically, by introducing the “sampled-data information flow” concept, a novel distributed control strategy is developed, which is more reliable and practical in the applications. Moreover, the velocity information is not required to be exchanged, such that the communication network load can be further reduced. Based on input-to-state stability, sufficient conditions are derived to guarantee that the attitude synchronization can be achieved under directed topology. An important and distinctive feature of the proposed method consists in the fact that it can effectively reduce the energy consumption for the spacecraft formation flying due to more efficient utilization of the communication network resources. Finally, a numerical example is presented to demonstrate the effectiveness and the benefit of our proposed method.

Synchronization of networked Euler-Lagrange systems by sampled-data communication with time-varying transmission delays under directed topology

This paper investigates the synchronization problem of networked Euler-Lagrange systems under directed topology, where the sampled-data communication is adopted with time-varying transmission delays. More precisely, sampled-data information is exchanged according to a unified sampling sequence instead of continuous-time communication, which is more reliable and practical in the applications. Additionally, the proposed strategy can be capable of both uniform and non-uniform sampling periods. Furthermore, from the energy point of view, potential benefit can be provided to reduce the communication energy consumption. Sufficient conditions are established to guarantee that the synchronization can be achieved in the scenarios with fixed and switching topologies. Finally, a numerical example is given to illustrate the performance of the proposed method.

Stability Analysis of Genetic Regulatory Networks With Switching Parameters and Time Delays

This paper is concerned with the exponential stability analysis of genetic regulatory networks (GRNs) with switching parameters and time delays. In this paper, a new integral inequality and an improved reciprocally convex combination inequality are considered. By using the average dwell time approach together with a novel Lyapunov–Krasovskii functional, we derived some conditions to ensure the switched GRNs with switching parameters and time delays are exponentially stable. Finally, we give two numerical examples to clarify that our derived results are effective.