All a b c d e f g h i j k l m n o p q r s t u v w x y z Other

Previous Page 4 Next

Displaying 61 – 80 of 116

Showing per page

Performance evaluation based fault tolerant control with actuator saturation avoidance

Boumedyen Boussaid, Christophe Aubrun, Mohamed Naceur Abdelkrim, Mohamed Koni Ben Gayed (2011)

International Journal of Applied Mathematics and Computer Science

In this paper, a new approach regarding a reconfigured system is proposed to improve the performance of an active fault tolerant control system. The system performance is evaluated with an intelligent index of performance. The reconfiguration mechanism is based on a model predictive controller and reference trajectory management techniques. When an actuator fault occurs in the system, a new degraded reference trajectory is generated and the controller calculates new admissible controls. A constraint...

Reconfigurability analysis for reliable fault-tolerant control design

Ahmed Khelassi, Didier Theilliol, Philippe Weber (2011)

International Journal of Applied Mathematics and Computer Science

In this paper the integration of reliability evaluation in reconfigurability analysis of a fault-tolerant control system is considered. The aim of this work is to contribute to reliable fault-tolerant control design. The admissibility of control reconfigurability is analyzed with respect to reliability requirements. This analysis shows the relationship between reliability and control reconfigurability defined generally through Gramian controllability. An admissible solution for reconfigurability...

Reconfigurable control design with integration of a reference governor and reliability indicators

Philippe Weber, Boumedyen Boussaid, Ahmed Khelassi, Christophe Aubrun (2012)

International Journal of Applied Mathematics and Computer Science

A new approach to manage actuator redundancy in the presence of faults is proposed based on reliability indicators and a reference governor. The aim is to preserve the health of the actuators and the availability of the system both in the nominal behavior and in the presence of actuator faults. The use of reference governor control allocation is a solution to distribute the control efforts among a redundant set of actuators. In a degraded situation, a reconfigured control allocation strategy is...

Reliable robust path planning with application to mobile robots

Romain Pepy, Michel Kieffer, Eric Walter (2009)

International Journal of Applied Mathematics and Computer Science

This paper is devoted to path planning when the safety of the system considered has to be guaranteed in the presence of bounded uncertainty affecting its model. A new path planner addresses this problem by combining Rapidly-exploring Random Trees (RRT) and a set representation of uncertain states. An idealized algorithm is presented first, before a description of one of its possible implementations, where compact sets are wrapped into boxes. The resulting path planner is then used for nonholonomic...

Robust and nonrobust tracking

Jan Štecha (1998)

Kybernetika

For zero steady state tracking error it is necessary to include n integrators in the control loop in the case of reference signal generated by n integrators. This result can be generalized to arbitrary n unstable modes of the reference generator according to the “internal model principle”. This paper shows an alternative solution of the asymptotic reference signal tracking problem using feedforward. The solution is not robust but gives a feedback controller with reduced complexity. Robust tracking...

Robust control of chaos in modified FitzHugh-Nagumo neuron model under external electrical stimulation based on internal model principle

Yuan Jiang, Jiyang Dai (2011)

Kybernetika

This paper treats the question of robust control of chaos in modified FitzHugh-Nagumo neuron model under external electrical stimulation based on internal model principle. We first present the solution of the global robust output regulation problem for output feedback system with nonlinear exosystem. Then we show that the robust control problem for the modified FitzHugh-Nagumo neuron model can be formulated as the global robust output regulation problem and the solvability conditions for the output...

Robust Control of Linear Stochastic Systems with Fully Observable State

Alexander Poznyak, M. Taksar (1996)

Applicationes Mathematicae

We consider a multidimensional linear system with additive inputs (control) and Brownian noise. There is a cost associated with each control. The aim is to minimize the cost. However, we work with the model in which the parameters of the system may change in time and in addition the exact form of these parameters is not known, only intervals within which they vary are given. In the situation where minimization of a functional over the class of admissible controls makes no sense since the value of...

Robust dynamic output feedback fault-tolerant control for Takagi-Sugeno fuzzy systems with interval time-varying delay via improved delay partitioning approach

Chao Sun, Fuli Wang, Xiqin He (2016)

Open Mathematics

This paper addresses the problem of robust fault-tolerant control design scheme for a class of Takagi-Sugeno fuzzy systems subject to interval time-varying delay and external disturbances. First, by using improved delay partitioning approach, a novel n-steps iterative learning fault estimation observer under H ∞ constraint is constructed to achieve estimation of actuator fault. Then, based on the online estimation information, a fuzzy dynamic output feedback fault-tolerant controller considered...

Robust fault detection of singular LPV systems with multiple time-varying delays

Amir Hossein Hassanabadi, Masoud Shafiee, Vicenç Puig (2016)

International Journal of Applied Mathematics and Computer Science

In this paper, the robust fault detection problem for LPV singular delayed systems in the presence of disturbances and actuator faults is considered. For both disturbance decoupling and actuator fault detection, an unknown input observer (UIO) is proposed. The aim is to compute a residual signal which has minimum sensitivity to disturbances while having maximum sensitivity to faults. Robustness to unknown inputs is formulated in the sense of the H∞ -norm by means of the bounded real lemma (BRL)...

Robust fractional adaptive control based on the strictly Positive Realness Condition

Samir Ladaci, Abdelfatah Charef, Jean Jacques Loiseau (2009)

International Journal of Applied Mathematics and Computer Science

This paper presents a new approach to robust adaptive control, using fractional order systems as parallel feedforward in the adaptation loop. The problem is that adaptive control systems may diverge when confronted with finite sensor and actuator dynamics, or with parasitic disturbances. One of the classical robust adaptive control solutions to these problems makes use of parallel feedforward and simplified adaptive controllers based on the concept of positive realness. The proposed control scheme...

Currently displaying 61 – 80 of 116