Data reconciliation for mineral and metallurgical processes : Contributions to uncertainty tuning and dynamic balancing : Application to control and optimization

Pour avoir un fonctionnement de l'usine sûr et bénéfique, des données précises et fiables sont nécessaires. D'une manière générale, une information précise mène à de meilleures décisions et, par conséquent, de meilleures actions pour aboutir aux objectifs visés. Dans un environnement industriel, les données souffrent de nombreux problèmes comme les erreurs de mesures (autant aléatoires que systématiques), l'absence de mesure de variables clés du procédé, ainsi que le manque de consistance entre les données et le modèle du procédé. Pour améliorer la performance de l'usine et maximiser les profits, des données et des informations de qualité doivent être appliquées à l'ensemble du contrôle de l'usine, ainsi qu'aux stratégies de gestion et d'affaires. Comme solution, la réconciliation de données est une technique de filtrage qui réduit l'impact des erreurs aléatoires, produit des estimations cohérentes avec un modèle de procédé, et donne également la possibilité d'estimer les variables non mesurées. Le but de ce projet de recherche est de traiter des questions liées au développement, la mise en œuvre et l'application des observateurs de réconciliation de données pour les industries minéralurgiques et métallurgiques. Cette thèse explique d’abord l'importance de régler correctement les propriétés statistiques des incertitudes de modélisation et de mesure pour la réconciliation en régime permanent des données d’usine. Ensuite, elle illustre la façon dont les logiciels commerciaux de réconciliation de données à l'état statique peuvent être adaptés pour faire face à la dynamique des procédés. La thèse propose aussi un nouvel observateur de réconciliation dynamique de données basé sur un sous-modèle de conservation de la masse impliquant la fonction d'autocovariance des défauts d’équilibrage aux nœuds du graphe de l’usine. Pour permettre la mise en œuvre d’un filtre de Kalman pour la réconciliation de données dynamiques, ce travail propose une procédure pour obtenir un modèle causal simple pour un circuit de flottation. Un simulateur dynamique basé sur le bilan de masse du circuit de flottation est développé pour tester des observateurs de réconciliation de données et des stratégies de contrôle automatique. La dernière partie de la thèse évalue la valeur économique des outils de réconciliation de données pour deux applications spécifiques: une d'optimisation en temps réel et l’autre de commande automatique, couplées avec la réconciliation de données. En résumé, cette recherche révèle que les observateurs de réconciliation de données, avec des modèles de procédé appropriés et des matrices d'incertitude correctement réglées, peuvent améliorer la performance de l'usine en boucle ouverte et en boucle fermée par l'estimation des variables mesurées et non mesurées, en atténuant les variations des variables de sortie et des variables manipulées, et par conséquent, en augmentant la rentabilité de l'usine.To have a beneficial and safe plant operation, accurate and reliable plant data is needed. In a general sense, accurate information leads to better decisions and consequently better actions to achieve the planned objectives. In an industrial environment, data suffers from numerous problems like measurement errors (either random or systematic), unmeasured key process variables, and inconsistency between data and process model. To improve the plant performance and maximize profits, high-quality data must be applied to the plant-wide control, management and business strategies. As a solution, data reconciliation is a filtering technique that reduces impacts of random errors, produces estimates coherent with a process model, and also gives the possibility to estimate unmeasured variables. The aim of this research project is to deal with issues related to development, implementation, and application of data reconciliation observers for the mineral and metallurgical industries. Therefore, the thesis first presents how much it is important to correctly tune the statistical properties of the model and measurement uncertainties for steady-state data reconciliation. Then, it illustrates how steady-state data reconciliation commercial software packages can be used to deal with process dynamics. Afterward, it proposes a new dynamic data reconciliation observer based on a mass conservation sub-model involving a node imbalance autocovariance function. To support the implementation of Kalman filter for dynamic data reconciliation, a procedure to obtain a simple causal model for a flotation circuit is also proposed. Then a mass balance based dynamic simulator of froth flotation circuit is presented for designing and testing data reconciliation observers and process control schemes. As the last part of the thesis, to show the economic value of data reconciliation, two advanced process control and real-time optimization schemes are developed and coupled with data reconciliation. In summary, the study reveals that data reconciliation observers with appropriate process models and correctly tuned uncertainty matrices can improve the open and closed loop performance of the plant by estimating the measured and unmeasured process variables, increasing data and model coherency, attenuating the variations in the output and manipulated variables, and consequently increasing the plant profitability

Human perception capabilities for socially intelligent domestic service robots

The daily living activities for an increasing number of frail elderly people represent a continuous struggle both for them as well as for their extended families. These people have difficulties coping at home alone but are still sufficiently fit not to need the round-the-clock care provided by a nursing home. Their struggle can be alleviated by the deployment of a mechanical helper in their home, i.e. a service robot that can execute a range of simple object manipulation tasks. Such a robotic application promises to extend the period of independent home living for elderly people, while providing them with a better quality of life. However, despite the recent technological advances in robotics, there are still some remaining challenges, mainly related to the human factors. Arguably, the lack of consistently dependable human detection, localisation, position and pose tracking information and insufficiently refined processing of sensor information makes the close range physical interaction between a robot and a human a high-risk task. The work described in this thesis addresses the deficiencies in the processing of the human information of today’s service robots. This is achieved through proposing a new paradigm for the robot’s situational awareness in regard to people as well as a collection of methods and techniques, operating at the lower levels of the paradigm, i.e. perception of new human information. The collection includes methods for obtaining and processing of information about the presence, location and body pose of the people. In addition to the availability of reliable human perception information, the integration between the separate levels of paradigm is considered to be a critically important factor for achieving the human-aware control of the robot. Improving the cognition, judgment and decision making action links between the paradigm’s layers leads to enhanced capability of the robot to engage in a natural and more meaningful interaction with people and, therefore, to a more enjoyable user experience. Therefore, the proposed paradigm and methodology are envisioned to contribute to making the prolonged assisted living of elderly people at home a more feasible and realistic task. In particular, this thesis proposes a set of methods for human presence detection, localisation and body pose tracking that are operating on the perception level of the paradigm. Also, the problem of having only limited visibility of a person from the on-board sensors of the robot is addressed by the proposed classifier fusion method that combines information from several types of sensors. A method for improved real-time human body pose tracking is also investigated. Additionally, a method for estimation of the multiple human tracks from noisy detections, as well as analysis of the computed human tracks for cognition about the social interactions within the social group, operating at the comprehension level of the robot’s situational awareness paradigm, is proposed. Finally, at the human-aware planning layer, a method that utilises the human related information, generated by the perception and comprehension layers to compute a minimally intrusive navigation path to a target person within a human group, is proposed. This method demonstrates how the improved human perception capabilities of the robot, through its judgement activity, ii ABSTRACT can be utilised by the highest level of the paradigm, i.e. the decision making layer, to achieve user friendly human-robot interactions. Overall, the research presented in this work, drawing on recent innovation in statistical learning, data fusion and optimisation methods, improves the overall situational awareness of the robot in regard to people with the main focus placed on human sensing capabilities of service robots. The improved overall situational awareness of the robot regarding people, as defined by the proposed paradigm, enables more meaningful human-robot interactions

State of the art survey of technologies applicable to NASA's aeronautics, avionics and controls program

The state of the art survey (SOAS) covers six technology areas including flightpath management, aircraft control system, crew station technology, interface & integration technology, military technology, and fundamental technology. The SOAS included contributions from over 70 individuals in industry, government, and the universities

Fault detection, isolation, and identification for nonlinear systems using a hybrid approach

This thesis presents a novel integrated hybrid approach for fault diagnosis (FD) of nonlinear systems; taking advantage of both system's mathematical model and the adaptive nonlinear approximation capability of computational intelligence techniques. Unlike most FD techniques, the proposed solution simultaneously accomplishes fault detection, isolation, and identification (FDII) within a unified diagnostic module. At the core of this solution are a bank of adaptive neural parameter estimators (NPE) and a set of single-parameterized fault models. The NPEs continuously estimate unknown fault parameters (FP) that are indicators of faults in the system. In view of the availability of full-state measurements, two NPE structures, namely series-parallel and parallel, are developed with their exclusive set of desirable attributes. The parallel scheme is extremely robust to measurement noise and possesses a simpler, yet more solid, fault isolation logic. On the contrary, the series-parallel scheme displays short FD delays and is robust to closed-loop system transients due to changes in control commands. Simple neural network architecture and update laws make both schemes suitable for real-time implementations. A fault tolerant observer (FTO) is then designed to extend the FDII schemes to systems with partial-state measurement. The proposed FTO is a neural state estimator that can estimate unmeasured states even in presence of faults. The estimated and the measured states then comprise the inputs to the FDII schemes. Simulation results for FDII of reaction wheels of a 3-axis stabilized satellite in presence of disturbances and noise demonstrate the effectiveness of the proposed FDII solution under both full and partial-state measurements