This paper presents a methodology for the design of reliable control systems by using multiple identical controllers to a given plant. The resulting closed-loop control system is reliable in the sense that it provides guaranteed internal stability and H∞ performance (in terms of disturbance attenuation), not only when all controllers are operational but also when some controller outages (sensor and/or actuator) occur. A numerical example is given to illustrate the proposed design procedures.

This paper is concerned with the reliable control design problem for uncertain nonlinear systems. A more practical model of actuator failures than outage is adopted. Based on the Hamilton-Jacobi inequality (HJI) approach from nonlinear control theory, a method for designing reliable state feedback controllers is presented. The resulting control systems are robustly stable and with an performance bound against plant uncertainty and actuator failures.

This paper is concerned with the reliable design problem for linear systems. A more practical model of sensor and actuator failures than outage is considered. Procedures for designing reliable controllers are presented for the case of sensor failures and actuator failures that can be modeled by a scaling factor and a disturbance. The resulting control systems are reliable in that they provide guaranteed asymptotic stability and H∞ performance when all control components (sensors and actuators) are operational as well as when some control components experience failures. A numerical example is also given to illustrate the design procedures and their electiveness.

This paper addresses the reliable H∞-control problems for affine nonlinear systems. Based on the Hamilton-Jacobi inequality approach developed in the H∞-control problems for affine nonlinear systems, a method for the design of reliable nonlinear control systems is presented. The resulting nonlinear control systems are reliable in that they provide guaranteed local asymptotic stability and H∞ performance not only when all control components are operational, but also in the case of some component outages within a prespecified subset of control components. A numerical example is also given. H∞ control, Hamilton-Jacobi inequalities, nonlinear systems, reliable control.

This paper is concerned with decentralized robust control design for a class of interconnected systems with time-varying uncertainties. The interconnected systems under consideration contain time-varying uncertain parameters whose values are unknown but bounded in given compact sets. Sufficient conditions under which a considered system can be quadratically stabilized by a linear decentralized feedback control for all admissible variations of uncertainties are given in terms of the structures of uncertainties. For the interconnected systems satisfying the stabilizability conditions, a decentralized control design procedure is also provided.