The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
To create a precise model structure and perform fault monitoring algorithms for a wide range of complex systems along with dynamic behavioural characteristics, the causal graph-based methods were considered herein. In this paper, a new scheme was devised based on fast fault detection mechanism relying on the Directed Hypergraph Observer model. The performance of the suggested pattern is illustrated...
Fault estimation is considered as one of the most essential problem in diagnosis domain. In this paper, a simultaneous state and fault estimation is treated for state time delay system. The fault estimation technique is based on H∞ optimization method to addressed the subject of robustness in the presence of disturbance and uncertainties. The fault estimation is made by using the Lyapunov Krasovskii...
This paper deals with actuator fault diagnosis of neutral delayed systems with multiple time delays using an unknown input observer. The main purpose is to design an observer that guarantees the asymptotic stability of the estimate error dynamics and the actuator fault detection. The existence conditions for such an observer are established. The main problem studied in this paper aims at designing...
A fault tolerant control synthesis is a key solution for great and several issues which threat system safety and may have critical and dangerous consequences especially in aeronautics, medicines and chemical industry. This is why, in this present work, an Active Fault Tolerant Control (AFTC) framework is designed using a linear adaptive observer-based fault detection and estimation tasks, into graphical...
This paper deals with a novel diagnosis framework for robust fault detection and estimation purposes by combining an ordinary Unknown Input Observer (UIO) with the port-Hamiltonian formalism. Based on energy aspect, the full order Unknown Input Hamiltonian Observer (UIHO) design scheme guarantees robust residual generation through decoupling the disturbances effects from the fault ones. The fault...
H∞ formulation of the robust fault tolerant control problem for uncertain systems with state time-delays is studied in this paper. A robust control law is then designed in order to automatically compensate actuator and sensor faults, based on a performance index as H∞ model-matching problem. Where, the gain is obtained via Linear Matrix Inequality (LMI) feasibility conditions. Indeed, a new condition...
This paper presents the design procedure of a global fault detection and isolation strategy for complex systems based on bond graph tool. The proposed method consists in establishing a word bond graph model and developing a local observer for each subsystem. The aim of the paper is to deal with the structural interconnection between these observers using structural and causal properties of the bond...
A new method of adaptive Luenberger observer design used on actuator fault detection and estimation is investigated. This approach is based on Bond Graph representation which is a multidisciplinary tool characterised by its causal, behavioral and structural properties for control and diagnosis analysis. Thus, the necessary existence conditions are taking in consideration. An hydraulic system with...
In this paper, a method of fault estimation based on unknown input observer is presented for a class of neutral time-delay system. First, an unknown input observer is described to achieve fault estimation for neutral time-delay system with a constant delay. An observability condition is generated to guarantee observer use. Then, the observer is used to generate an algebraic method of actuator fault...
This paper deals with a fault detection and isolation for linear systems using causal graphical approaches. The monitoring based on qualitative models (Signed Directed Graph) enhance fault localization by analyzing initial and final responses of system variables due to deviations, these dynamic behaviors are deduced using causal paths and propagations from the fault node to system variable node. However,...
This paper deals with the design of a robust fault detection filter for a two stage chemical reactor which is a complex process, susceptible to faults, that can minimize productivity and humans safety. This process is considered as a time-delay system with both unknown inputs and parameter uncertainties. Therefore, a multi-objective optimization technique is used to introduce a new performance index...
In this paper, causal graphical models based approach for Fault Detection and Isolation (FDI) are adressed. Due to the structural and causal properties of a bond graph tool, a residual generation is based on analytical redundancy relations (ARRs) witch are obtained from the system behavior through different procedures in order to eliminate unknown variables (covering causal paths). Thus, the qualitative...
This paper deals with the robust actuator fault diagnosis by using an Unknown Input Observer (UIO). The proposed UIO design guarantees robust residual generation through decoupling the disturbances effects from the fault ones. A Generalized Observer Scheme (GOS) based on a bank of unknown input observers is exploited for fault isolation. The fault estimation is, then, allowed by an algebraic transformation...
The present paper deals with a Luenberger observer design by using a causal graphical approach. Causal proprieties and structural analysis of a Bond Graph tool are involved to build classical linear observers. The residual sensitivity analysis improves the efficiency of the fault detection estimator. Simulation tests on a DC motor show the performance of the developed graphical linear observer in...
In this paper, fault detection and isolation for non linear systems using causal graphical approaches are presented. A diagnosis based on signed directed graph (qualitative model) is provided by determining initial and final responses using forward and backward propagation. Moreover, a bond graph (quantitative model) is used to generate Analytical Redundancy Relations (ARRs) through causal paths....
An active control law design for uncertain linear systems with state time-delay is addressed in this paper, in order to guarantee dynamic performances and compensate fault effects. First, the fault tolerant control strategy is designed based on Frobenius norm by minimizing the distance between the closed-loop model of the faulty system and a reference one. Therefore, stability issue is ensured via...
In this article, a control strategy based on fuzzy approach is proposed for mobile robots with only some states measurement feedback to ensure a stable and accurate navigation, reach a predefined target and avoid obstacle. This approach is applied to a mobile robot like a truck with two trailers attached, witch are added to raise the complexity problem. The simulation results show that the designed...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.