Tinggang Jia

Output-feedback control design for NCSs subject to quantization and dropout

In this paper, the output-feedback control problem is considered for networked systems involving in signal quantization and data packet dropout. The states of the controlled system are unavailable and the output signals are quantized before being communicated. An estimation method is introduced to cope with the effect of random packet loss that is modelled as a Bernoulli process. The quantized measurement signals are dealt with by utilizing the sector bound method, in which the quantization error is treated as sector-bounded uncertainty. The output-feedback controller is designed which guarantees the closed-loop system is exponentially mean-square stable. The simulation example is given to illustrate the proposed method.

Sliding mode control for stochastic systems subject to packet losses

This paper investigates the problem of sliding mode control for stochastic system under the effect of packet dropout. In this work, a new sliding function dependent on the probability of packet dropout is constructed. By means of a Lyapunov function involved in sliding mode variable and system state, both the reachabiltiy and the stability are analyzed simultaneously, and the sufficient condition is derived via linear matrix inequalities. Finally, numerical simulation results are given.

Networked predictive control of constrained linear systems with input quantisation

This article investigates the problem of stabilising predictive control for constrained systems, wherein communication from the controller to the plant input is through a digital channel subject to quantisation and delay. A novel model with structured norm-bounded uncertainties is proposed to describe control system with input quantisation. Under a multirate scheme, a delay compensation strategy is presented. The networked predictive control synthesis approach is developed by solving a finite receding horizon optimisation problem with free control moves. It is shown that the proposed predictive controller not only efficiently reduces the negative effects of the quantisation and communication delays but also guarantees the closed-loop stability and satisfies constraints. Finally, a simulation example illustrates the effectiveness of the derived method.

Design of sliding mode control for a class of uncertain switched systems

This paper considers the problem of sliding mode control for a class of uncertain switched systems with parameter uncertainties and external disturbances. A key feature of the controlled system is that each subsystem is not required to share the same input channel, which was usually assumed in some existing works. By means of a weighted sum of the input matrix, a common sliding surface is designed in this work. It is shown that the reachability of the sliding surface can be ensured by the present sliding mode controller. Moreover, the sliding motion on the specified sliding surface is asymptotically stable under the proposed switching signal dependent on the state and time. Additionally, the above results are further extended to the case that the system states are unavailable. Both the sliding surface and sliding mode controller are designed by utilising state-observer. Finally, numerical simulation examples are given to illustrate the effectiveness of the present method.

Robust fuzzy control for stochastic Markovian jumping systems via sliding mode method

This paper considers the problem of sliding mode control for stochastic Markovian jumping systems by means of fuzzy method. The Takagi–Sugeno (T–S) fuzzy stochastic model subject to state-dependent noise is presented. A key feature in this work is to remove the restricted condition that each local system model had to share the same input channel, which is usually assumed in some existing results. The integral sliding surface is constructed for every mode and the connections among various sliding surfaces are established via a set of coupled matrices. Moreover, the present sliding mode controller including the transition rates of modes can cope with the effect of Markovian switching. It is shown that both the reachability of sliding surfaces and the stability of sliding mode dynamics can be ensured. Finally, numerical simulation results are given.

Reliable Sliding-Mode Control for Markovian Jumping Systems Subject to Partial Actuator Degradation

In this work, a novel robust sliding-mode control (SMC) method has been provided for uncertain stochastic Markovian jumping systems subject to actuator degradation, such that the closed-loop system is globally asymptotically stable (with probability one). In the design of switching functions, a set of specified matrices are employed such that the connections among sliding surfaces corresponding to each mode are established. Then, a sliding-mode controller is synthesized to ensure the reachability of the specified switching surface despite actuator degradation and uncertainties. Finally, the simulation results illustrate the proposed method and the effectiveness.

Adaptive neural control for uncertain systems subject to actuator failure

In this paper, the design of controller based on neural network is investigated for a class of uncertain systems subject to actuator failures. An adaptive neural controller is designed by utilizing the approximation technique of neural network. The key feature in this work is to remove the requirement on the boundedness of unknown nonlinear functions that is usually encountered in the existing works. Moreover, sufficient conditions are derived such that the closed-loop system is robustly stable. Finally, numerical simulation results are given.

Multirate Event-Triggered MPC for NCSs with Transmission Delays

This paper investigates the event-triggered model predictive control problem for networked control systems with transmission delays. Based on a multirate scheme, an event-triggered delay compensation strategy is proposed. The event-triggered predictive control algorithm with feasibility and stability guarantee is built upon the triggered conditions that determine whether the measurements are transmitted. The results are further extended to a self-triggered mechanism to avoid continuous monitoring of measurements difference. Finally, simulation results are given to illustrate the effectiveness of the proposed methods.