Showing papers by "Peng Shi published in 1998"

Filtering on sampled-data systems with parametric uncertainty

Abstract: The paper is concerned with the problem of robust H/sub /spl infin// filtering for a class of systems with parametric uncertainties and unknown time delays under sampled measurements. The parameter uncertainties considered are real time-varying and norm-bounded, appearing in the state equation. An approach has been proposed for the designing of H/sub /spl infin// filters, using sampled measurements, which would guarantee a prescribed H/sub /spl infin// performance in the continuous-time context, irrespective of the parameter uncertainties and unknown time delays. Both cases of finite and infinite horizon filtering are studied. It has been shown that the above robust H/sub /spl infin//-filtering problem can be solved in terms of differential Riccati inequalities with finite discrete jumps.

Robust disturbance attenuation with stability for a class of uncertain singularly perturbed systems

Abstract: In this paper, the problem of robust stability and robust disturbance attenuation is investigated for a class of singularly perturbed linear systems with norm-bounded parameter uncertainties in both state and output equations. Based on the slow and fast subsystems, a composite linear controller is designed such that both robust stability and a prescribed H infinity performance for the full-order system are achieved, irrespective of the uncertainties. Our results show that the above problem can be converted to an H infinity control problem for a related singularly perturbed linear system without parameter uncertainty. Thus, the existing results on H infinity control of singularly perturbed systems can be applied to obtain solutions to the problem of robust H infinity control for the uncertain systems, which is independent of the singular perturbation epsilon when epsilon is sufficiently small. An example is given to show the potential of the proposed technique.

On asymptotic optimization of a class of nonlinear stochastic hybrid systems

Abstract: We consider the problem of control for continuous time stochastic hybrid systems in finite time horizon. The systems considered are nonlinear: the state evolution is a nonlinear function of both the control and the state. The control parameters change at discrete times according to an underlying controlled Markov chain which has finite state and action spaces. The objective is to design a controller which would minimize an expected nonlinear cost of the state trajectory. We show using an averaging procedure, that the above minimization problem can be approximated by the solution of some deterministic optimal control problem. This paper generalizes our previous results obtained for systems whose state evolution is linear in the control.

Design of robust controller for linear systems with Markovian jumping parameters

Abstract: This paper deals with the robustness of the class of uncertain linear systems with Markovian jumping parameters (ULSMJP). The uncertainty is taken to be time-varying norm bounded. Under the assumptions of the boundedness of the uncertainties and the complete access to the system's state and its modes, a sufficient condition for stochastic stabilizability of this class of systems is established. An example is provided to demonstrate the usefulness of the proposed theoretical results.

Robust Aircraft Control Design for Glideslope Capture in Windshear Using Gain Scheduling

Abstract: Design of a robust automatic landing controller for the glideslope capture under windshear conditions is presented in this paper. Ha robust technique is employed to develop the necessary formulations for the aircraft control gain. Gain scheduling control inputs are determined so as to recover the glideslope trajectory in all stages of windshear. It is shown that the aircraft lift affected by the windshear can be separated into three parts: ballooning due to head wind, downburst, and combination of downburst with tail wind. In order to adjust the loss or increase in lift due to windshear, the robust gain scheduling controller is designed based on the change in aircraft lift caused by the windshear. Simulation results show that the glideslope capture of the landing aircraft can be recovered under different kinds of windshear. L INTRODUCTION

H/sub /spl infin// control of discrete-time linear uncertain systems with delayed-state

Abstract: The paper is concerned with H/sub /spl infin// control for discrete time-delay linear systems with parametric uncertainty. We study the problem of robust H/sub /spl infin// state feedback control in which both robust stability and a prescribed H/sub /spl infin// performance are required to be achieved irrespective of the uncertainty and unknown time-delay.

H/sub /spl infin// control for discrete-time linear systems with Frobenius norm-bounded uncertainties

Abstract: In this paper, we consider the problems of robust stability and control for the class of uncertain discrete-time linear systems with Frobenius norm-bounded parameter uncertainties in all matrices of the system and output equations. Necessary and sufficient conditions for the above problems are proposed. A linear static state feedback control law is designed, which is in terms of a Riccati inequality.

Application of h* robust technique for control of uncertain wave equations

Abstract: Application of H^ robust technique for control of one-dimensional uncertain wave equations by a distributed force is studied in this paper. The wave equation may contain uncertainties in the coefficients multiplying various derivatives and viscous damping terms. Linear //«, robust controller is known to stabilize systems with certain types of bounded uncertainties; it is employed in this study to control the wave equation with positive or negative bounded damping coefficients, as well as the time-varying coefficients. It is shown that the robust control gain obtained from the solution of a partial differential Riccati equation can be used to stabilize the uncertain wave systems. Numerical simulation results illustrate the potential of the proposed method.

Hm Control of Discrete-Time Linear Uncertain with Delayed-State

Abstract: This paper concerns with H, control for discrete timedelay linear systems with parametric uncertainty. We study the problem of robust H, state feedback control in which both robust stability and a prescribed H, performance are required to be achieved irrespective of the uncertainty and unknown time-delay.

Optimal and robust control of a group of single-input linear systems using linear uncertain technique

Abstract: Optimal and robust control of a group of single-input linear systems are presented. The formulation of the optimal state feedback controller is developed for a group of linear systems derived from a nonlinear system under attractive domains. Choosing a particular linear system as the desired model, the rest of the systems are assumed to be parameter-uncertain. Selection of a suitable weighting matrix for the performance index is used as a key method to optimally control this particular system and robustly stabilize the rest of the linear systems, simultaneously. It is shown that the above problem can be solved if an algebraic Riccati equation (ARE) has a solution. The state weighting matrix of this ARE can be linearly formulated for all uncertain coefficients and factors. If the weighting matrix is selected to satisfy certain constraints, the solution of ARE is positive, and all closed loop systems are stable. Control of a group of linearized longitudinal motions of an aircraft is employed to illustrate the potential of the proposed method.