Commande et surveillance des systemes a evenements discrets complexes: application aux ateliers flexibles

SIGLEAvailable from INIST (FR), Document Supply Service, under shelf-number : T 82365 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Vers l'intégration diagnostic-pronostic pour la maintenance des systèmes complexes

TOULOUSE3-BU Sciences (315552104) / SudocSudocFranceF

Sur la distribution avec redondance partielle de modèles à événements discrets pour la supervision de procédés industriels

TOULOUSE3-BU Sciences (315552104) / SudocSudocFranceF

MEDITO: A Logic-Based Meta-diagnosis Tool

Abstract—In every Model-Based Diagnosis (MBD) approach, a model of a real-world system and some observations of such a system are used by a diagnostic algorithm to compute diagnoses. Contrary to MBD classical hypotheses, real-world applications provide us with empirical data suggesting that diagnostic systems, i.e. a model, observations and a diagnostic algorithm, are sometimes abnormal with respect to some required properties. This is where Meta-Diagnosis comes into play with a theory to determine abnormalities in diagnostic systems. Unfortunately, Artificial Intelligence lacks of a tool putting meta-diagnosis theory to practice. Our first contribu-tion in this paper is such a tool, called MEDITO. Moreover, we provide a real-world example of MEDITO’s application at meta-diagnosing an Airbus landing gear extraction and retraction system with successful results

A generic ageing model for prognosis - Application to Permanent Magnet Synchronous Machines

International audienceIn the context of more electrical aircrafts, Permanent Magnet Synchronous Machines are used in a more and more aggressive environment. It becomes necessary to supervise their health state and to predict their future evolution and remaining useful life in order to anticipate any requested maintenance operation. Model-based prognosis is a solution to this issue. A generic modeling framework is proposed in this paper in order to implement such a prognosis method which relies on knowledge about the system ageing. A review of existing ageing laws is presented, and motivates the choice to developp an ageing model that could incorporates every kind of ageing laws. A generic ageing model is then defined, that allows representing the ageing of any equipment and the impact of this ageing on its environment. It includes the possible retroaction of the system health state to itself through stress increase in case of damage. The proposed ageing model is then illustrated with Permanent Magnet Synchronous Machines. A fictive but realistic scenario of stator ageing is built. It comprises apparition and progression of an inter-turns short-circuit and its impact on stator temperature, which value has an impact on the ageing speed. A prognosis method based on the generic ageing model is proposed, and applied successfully to this scenario

Synchronous machine faults detection and isolation for electro-mechanical actuators in aeronautics

International audienceThe reported work is the design of a Fault Detection and Isolation system for an innovative 12-slots 10-poles synchronous machine that becomes more and more popular in aeronautics. Two main faults occurring on this machine are identified as inter-turns short-circuit and rotor single pole demagnetization, and characterized. An analytical model of the motor is developped using Matlab Simulink. This model allows simulating nominal and faulty motor behaviour. It is parameterizable and is able to simulate several stages of degradation. Specific indicators are proposed for each fault. They do not require additional material or sensors since they are based on the signals already monitored for the machine control. Inter-turns short-circuit and pole demagnetization are successfully detected and identified