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Robust H ∞ control of an uncertain system via a stable decentralized output feedback controller

Ian R. Petersen (2009)

Kybernetika

This paper presents a procedure for constructing a stable decentralized output feedback controller for a class of uncertain systems in which the uncertainty is described by Integral Quadratic Constraints. The controller is constructed to solve a problem of robust H ∞ control. The proposed procedure involves solving a set of algebraic Riccati equations of the H ∞ control type which are dependent on a number of scaling parameters. By treating the off-diagonal elements of the controller transfer function...

Robust identification of parasitic feedback disturbances for linear lumped parameter systems

Vyacheslav Maksimov, Luciano Pandolfi (2001)

International Journal of Applied Mathematics and Computer Science

We study the problem of identification of an input to a linear finite-dimensional system. We assume that the input has a feedback form, which is related to a problem often encountered in fault detection. The method we use is to embed the identification problem in a class of inverse problems of dynamics for controlled systems. Two algorithms for identification of a feedback matrix based on the method of feedback control with a model are constructed. These algorithms are stable with respect to noise-corrupted...

Robust multisensor fault tolerant model-following MPC design for constrained systems

Alain Yetendje, Maria M. Seron, José A. De Doná (2012)

International Journal of Applied Mathematics and Computer Science

In this paper, a robust fault-tolerant control strategy for constrained multisensor linear systems, subject to sensor faults and in the presence of bounded state and output disturbances, is proposed. The scheme verifies that, for each sensors-estimator combination, suitable residual variables lie inside pre-computed sets and selects a more appropriate combination based on a chosen criterion. An active fault tolerant output feedback controller yields an MPC-based control law and, by means of the...

Robust nonlinear observer design for actuator fault detection in diesel engines

Boulaid Boulkroune, Issam Djemili, Abdel Aitouche, Vincent Cocquempot (2013)

International Journal of Applied Mathematics and Computer Science

This paper is concerned with actuator fault detection in nonlinear systems in the presence of disturbances. A nonlinear unknown input observer is designed and the output estimation error is used as a residual for fault detection. To deal with the problem of high Lipschitz constants, a modified mean-value theorem is used to express the nonlinear error dynamics as a convex combination of known matrices with time-varying coefficients. Moreover, the disturbance attenuation is performed using a modified...

Robust observer-based finite-time H ∞ control designs for discrete nonlinear systems with time-varying delay

Yali Dong, Huimin Wang, Mengxiao Deng (2021)

Kybernetika

This paper investigates the problem of observer-based finite-time H ∞ control for the uncertain discrete-time systems with nonlinear perturbations and time-varying delay. The Luenberger observer is designed to measure the system state. The observer-based controller is constructed. By constructing an appropriated Lyapunov-.Krasovskii functional, sufficient conditions are derived to ensure the resulting closed-loop system is H ∞ finite-time bounded via observer-based control. The observer-based controller...

Robust pole placement for second-order systems: an LMI approach

Didier Henrion, Michael Šebek, Vladimír Kučera (2005)

Kybernetika

Based on recently developed sufficient conditions for stability of polynomial matrices, an LMI technique is described to perform robust pole placement by proportional-derivative feedback on second-order linear systems affected by polytopic or norm-bounded uncertainty. As illustrated by several numerical examples, at the core of the approach is the choice of a nominal, or central quadratic polynomial matrix.

Robust prevention of limit cycles for robustly decoupled car steering dynamics

Jürgen Ackermann, Tilman Bünte (1999)

Kybernetika

Considerable safety benefits are achieved by robustly decoupling the lateral and yaw motions of a car with active steering. Robust unilateral decoupling requires an actuator to generate an additional front wheel steering angle. However, introducing actuators to closed loop systems may cause limit cycles due to actuator saturation and rate limits. Such limit cycles are intolerable w.r.t. safety and comfort. By introducing a simple nonlinear modification of the control law, this paper proposes a remedy...

Robust quasi NID aircraft 3D flight control under sensor noise

Marian J. Błachuta, Valery D. Yurkevich, Konrad Wojciechowski (1999)

Kybernetika

In the paper the design of an aircraft motion controller based on the Dynamic Contraction Method is presented. The control task is formulated as a tracking problem for Euler angles, where the desired decoupled output transients are accomplished under assumption of high-level, high-frequency sensor noise and incomplete information about varying parameters of the system and external disturbances. The resulting controller has a simple form of a combination of a low-order linear dynamical system and...

Robust quasi-LPV model reference FTC of a quadrotor UAV subject to actuator faults

Damiano Rotondo, Fatiha Nejjari, Vicenç Puig (2015)

International Journal of Applied Mathematics and Computer Science

A solution for fault tolerant control (FTC) of a quadrotor unmanned aerial vehicle (UAV) is proposed. It relies on model reference-based control, where a reference model generates the desired trajectory. Depending on the type of reference model used for generating the reference trajectory, and on the assumptions about the availability and uncertainty of fault estimation, different error models are obtained. These error models are suitable for passive FTC, active FTC and hybrid FTC, the latter being...

Rotary inverted pendulum: trajectory tracking via nonlinear control techniques

Luis E. Ramos-Velasco, Javier Ruiz, Sergej Čelikovský (2002)

Kybernetika

The nonlinear control techniques are applied to the model of rotary inverted pendulum. The model has two degrees of freedom and is not exactly linearizable. The goal is to control output trajectory of the rotary inverted pendulum asymptotically along a desired reference. Moreover, the designed controller should be robust with respect to specified perturbations and parameters uncertainties. A combination of techniques based on nonlinear normal forms, output regulation and sliding mode approach is...

Simultaneous state and parameter estimation based actuator fault detection and diagnosis for an unmanned helicopter

Chong Wu, Juntong Qi, Dalei Song, Xin Qi, Jianda Han (2015)

International Journal of Applied Mathematics and Computer Science

Simultaneous state and parameter estimation based actuator fault detection and diagnosis (FDD) for single-rotor unmanned helicopters (UHs) is investigated in this paper. A literature review of actuator FDD for UHs is given firstly. Based on actuator healthy coefficients (AHCs), which are introduced to represent actuator faults, a combined dynamic model is established with the augmented state containing both the flight state and AHCs. Then the actuator fault detection and diagnosis problem is transformed...

Sliding mode methods for fault detection and fault tolerant control with application to aerospace systems

Christopher Edwards, Halim Alwi, Chee Pin Tan (2012)

International Journal of Applied Mathematics and Computer Science

Sliding mode methods have been historically studied because of their strong robustness properties with regard to a certain class of uncertainty, achieved by employing nonlinear control/injection signals to force the system trajectories to attain in finite time a motion along a surface in the state-space. This paper will consider how these ideas can be exploited for fault detection (specifically fault signal estimation) and subsequently fault tolerant control. It will also describe applications of...

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