Luo Xiaoyuan

Leader-following formation control of multi-agent networks based on distributed observers

To investigate the leader-following formation control, in this paper we present the design problem of control protocols and distributed observers under which the agents can achieve and maintain the desired formation from any initial states, while the velocity converges to that of the virtual leader whose velocity cannot be measured by agents in real time. The two cases of switching topologies without communication delay and fixed topology with time-varying communication delay are both considered for multi-agent networks. By using the Lyapunov stability theory, the issue of stability is analysed for multi-agent systems with switching topologies. Then, by considering the time-varying communication delay, the sufficient condition is proposed for the multi-agent systems with fixed topology. Finally, two numerical examples are given to illustrate the effectiveness of the proposed leader-following formation control protocols.

Finite-time consensus of heterogeneous multi-agent systems

We investigate the finite-time consensus problem for heterogeneous multi-agent systems composed of first-order and second-order agents. A novel continuous nonlinear distributed consensus protocol is constructed, and finite-time consensus criteria are obtained for the heterogeneous multi-agent systems. Compared with the existing results, the stationary and kinetic consensuses of the heterogeneous multi-agent systems can be achieved in a finite time respectively. Moreover, the leader can be a first-order or a second-order integrator agent. Finally, some simulation examples are employed to verify the efficiency of the theoretical results.

Exponential stability criteria for uncertain stochastic systems

This paper considers the problem of delay-dependent exponential stability in mean square for a class of stochastic systems with polytopic-type uncertainties and time-varying delay. Based on the application of the descriptor model transformation and free weighting matrices to express this relationship among the system variables and among the terms in the Newton-Leibniz formula, some new delay-dependent exponential stability criteria are obtained in terms of linear matrix inequalities (LMIs). The new criteria are less conservative than existing ones. Numerical examples demonstrate the new criteria are effective and are an improvement over existing ones.

Automatic generation of minimally persistent formations using rigidity matrix

In this paper, the methods for generating minimally rigid formations and minimally persistent formations, is studied by using the rigidity matrix. Based on the properties of rigidity matrix, three algorithms are proposed. Firstly, the algorithm 1 is designed to generate the minimally rigid graphs in r-Dimension (r=2,3,…) workspace through some operations to the rigidity matrix; Secondly, the formations with range constraints are considered, and the algorithm 2 is presented to judge the minimally rigid feasibility of a formation; thirdly, the algorithm 3 gives some operations to direct the edges of minimally rigid graphs to generate minimally persistent graphs. At last, some simulations are provided to show the efficiency of our research.

The high performance controller design for Networked Control Systems with Multi-packet Transmission

This paper presents the model of multiple-packet transmission networked control system (MNCS) with simultaneous consideration of data packet dropouts and quantization. The relationship between quantization error and the communication rate is given. Then we propose the high performance controller design architecture for the MNCS, by exploiting the method of generalized internal model control. We shall call our architecture as networked internal model control (NIMC), which can overcome the conflict between system performance and network characteristic. Then an illustrative example is provided to show the advantage and applicability of the developed method for network-based controller design.

Observer-based adaptive fault-tolerant control for a class of nonlinear time-delay systems

The problem of fault-tolerant control for a class of nonlinear time-delay systems is investigated based on the observer technique. An adaptive observer and adaptive fault-tolerant controller are designed in proposed approach. Firstly, the adaptive observer is utilized to give a real time estimation of the fault. Then, an adaptive fault-tolerant controller is designed according to the estimation of the fault. The asymptotic stability of the closed-loop system is proved by Lyapunov theory both in normal case and fault case. Finally, the simulation results of the aircraft example illustrate that this method is effective and feasible.

Robust fault-tolerant satisfied control for time-delay uncertain systems

This paper deals with the methods of robust fault tolerant satisfied control for time-delay uncertain systems with actuator fault by using the approach of linear matrix inequality satisfying the condition of finite time bounded stability. The sufficient conditions which are able to realise robust fault tolerant satisfied control of the systems are obtained with both continuous time and discrete time cases, respectively. Furthermore, we obtain the results of robust fault-tolerant satisfied control with integrity for the actuator fault systems.