Event-triggered bipartite consensus of multi-agent systems in signed networks

<abstract><p>This paper focuses on the event-triggered bipartite consensus of multi-agent systems in signed networks, where the dynamics of each agent is assumed to be Lur'e system, and both the cooperative interaction and antagonistic interaction are allowed among neighbor agents. A novel event-triggered communication scheme is presented to save limited network resources, and distributed bipartite control techniques are raised to address the bipartite leaderless consensus and bipartite leader-following consensus respectively. By virtue of the Lyapunov stability theory and algebraic graph theory, bipartite consensus conditions are derived, which can be easily solved by MATLAB. In addition, the upper bounds of the sampling period and triggered parameter can be estimated. Finally, two examples are employed to show the validity and advantage of the proposed transmission scheme.</p></abstract>

Popov-H∞ Robust Path-Tracking Control of Autonomous Ground Vehicles with Consideration of Sector Bounded Kinematic Nonlinearity

This paper proposes a new approach to cope with the kinematic nonlinearity in the H∞ vehicle path-tracking controller synthesis problem. The kinematic nonlinearity presented in the vehicle lateral error state is found to satisfy the sector-bound condition. By isolating the sector bounded nonlinearity via an upper linear fractional transformation (LFT), a Lur'e system is formulated. A nominal robust controller is synthesized to meet both the Popov-H∞ criterion and the regional pole placement requirement. A polytopic gain-scheduling technique is subsequently employed to accommodate the effect of the varying vehicle longitudinal velocity. Finally, an instant-turning maneuver and a sharp lane-changing maneuver are tested in CarSim-Simulink joint simulations whose results demonstrate the superiority of the proposed Popov-H∞ controller over a conventional H∞ controller.

Hinf State-feedback Control for Discrete-time Markov jump Lur'e system

We propose LMI conditions for H1 analysis and state-feedback control of discrete-time Markov Jump Lur'e systems. We will also approach two possible situations, either mode-dependent and modeindependent state-feedback control. For the first approach, we consider that the controller has access to the Markov mode (k), on the other hand, for the second approach, we consider that the Markov parameter (k) cannot be read by the controller. A numerical example illustrates the obtained results.

On Delay-dependent and Delay-derivative-dependent Stability and Stabilization for Lur’e Systems with Slow-varying Delay

This note is concerned with the absolute stability for time-varying delay Lur’e system with sector-bounded nonlinearity. Improved delay-dependent and delay-derivative-dependent stability criteria are obtained in the form of linear matrix inequalities (LMIs) by constructing a modified augmented Lyapunov-Krasovskii (LK) functional without applying the model transformation or the bounding techniques for cross terms. Thus, the presented delay-dependent criteria are less conservative than those in the literature. Moreover, state feedback stabilizing controllers based on the proposed stability criteria are designed. Numerical example demonstrates the effectiveness and superiority of the proposed method.

Improving Disturbance Rejection in Nonlinear Active Magnetic Bearing Systems: Using Lur'e Formulation

The efficacy of magnetic bearing controllers designed to reject transient disturbances is evaluated via a series of experiments. The experiment consists of a rocking beam with opposing electromagnetic actuators for control as well as an actuator for applying a disturbance torque. Controller synthesis employed a generalized Lur'e system approach to accommodate the nonlinear magnetization behavior of the electromagnetic actuator iron. Experimental results demonstrate significant improvements in disturbance rejection with controllers based upon the Lur'e system approach. Good agreement between simulation and experimental results was obtained, providing confidence that similar benefits can be achieved in industrial machinery employing active magnetic bearings.

New Results on Stability Analysis of Uncertain Neutral-Type Lur’e Systems Derived from a Modified Lyapunov-Krasovskii Functional

This paper is concerned with the problem of the absolute and robustly absolute stability for the uncertain neutral-type Lur’e system with time-varying delays. By introducing a modified Lyapunov-Krasovskii functional (LKF) related to a delay-product-type function and two delay-dependent matrices, some new delay-dependent robustly absolute stability criteria are proposed, which can be expressed as convex linear matrix inequality (LMI) framework. The criteria proposed in this paper are less conservative than some recent previous ones. Finally, some numerical examples are presented to show the effectiveness of the proposed approach.