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Control systems are being embedded in an ever-increasing number of applications, many of them unfeasible prior to the joined advances in control, solid state technology and microelectronics design. In the era of information, communication and technology, society continuously absorbs new technologies and quickly demands new tools, services and commodities that require challenging control techniques operated at high sample rates. However, the implementation of modern control systems is by no means straightforward and requires multidisciplinary knowledge in fields of control, hardware and software design. Complex control laws with demanding real-time constraints are usually implemented using high-end devices combined with some custom logic in project-dependent, hence non-reusable solutions. Such high-end devices are intended to be flexible enough to cover a wide range of applications and therefore their architectural complexity often leads to inefficient control solutions in terms of power consumption, area and even performance. Furthermore, in order to fulfil the real-time requirements, complex device-dependent arithmetic routines have to be usually hand crafted in assembly language as most modern compilers are unable to make use of the narrow data vector instructions that are especially tailored for signal processing applications, and sometimes, the required performance can only be reached by a number of these devices running in parallel. This thesis presents a comprehensive study of embedded real-time control implementations, bringing together hardware/software co-design, development tools and controller formulation aspects under a common framework that leads to a novel design methodology.

L’objectif de ce travail de thèse est de présenter des résultats expérimentaux ducontrôle de la température au sein d’une serre. Des techniques de commande de types PIDet LQG, ajustées à l’aide de l’identfication et des techniques de commande sans modèle sontappliquées au processus complexe de régulation des paramètres climatiques sous serre. Les résultatsobtenus nous ont permis d’envisager à terme une meilleure maîtrise des paramètresclimatiques. La mise en oeuvre de ces contrôleurs requiert généralement la réalisation d’undispositif électronique piloté par ordinateur doté d’une carte d’acquisition et de restitution desdonnées. Cette carte qui est aussi associée aux circuits électroniques permet de réaliser l’acquisition,le traitement et le stockage des données climatiques (température, humidité relativede l’air, et teneur en CO2). Elle permet en outre une meilleure adaptation de la puissancefournie aux différents actionneurs installés au sein de la serre. Des interfaces graphiques ontété développées, en utilisant le logiciel SIMULINK/Matlab. Ces derniers rassemblent à la foisune rapidité de fonctionnement, une facilité d’utilisation et une interactivité et une puissancede traitement en temps réel de l’ensemble des données. / The principal aim of this thesis is to present the experimental results for controllingtemperature under greenhouse. The PID and LQG controllers are inevitably adjusted by theidentification and the model free control also was implemented to the complex system in orderto regulate the climatic parameters under greenhouse. The obtained results shows the goodperformances for monitoring these parameters. The greenhouse environment is automated withseveral actuators and sensors that are connected to an acquisition and control system basedon a personal computer . This later is associated with electronic circuits allows to protectthe acquisition card against overvoltages and perform the acquisition, treatment and storageof climate data (temperature, relative humidity of the air, and content of CO2). It permitsfurthermore to obtain a good adaptation power given to the actuators that installed in thegreenhouse. Graphical interfaces have been developed using the Simulink/Matlab software.these later bring together both speed foncionnement, ease of use and interactivity and powerof processing the data in real-time.

The aim of this work is to explore the potential and to enhance the capability of evolutionary computation in the development of novel and advanced methodologies that enable control system structural optimisation and design automation for practical applications. Current design and optimisation methods adopted in control systems engineering are in essence based upon conventional numerical techniques that require derivative information of performance indices. These techniques lack robustness in solving practical engineering problems, which are often of a multi-dimensional, multi-modal nature. Using those techniques can often achieve neither global nor structural optimisation. In contrast, evolutionary mechanism learning tools have the ability to search in a multi-dimensional, multi-modal space, but they can not approach a local optimum as a conventional calculus-based method. The first objective of this research is to develop a reliable and effective evolutionary algorithm for engineering applications. In this thesis, a globally optimal evolutionary methodology and environment for control system structuring and design automation is developed, which requires no design indices to be differentiable. This is based on the development of a hybridised GA search engine, whose local tuning is tremendously enhanced by the incorporation of Hill-Climbing (HC), Simulated Annealing (SA) and Simplex techniques to improve the performance in search and design. A Lamarckian inheritance technique is also developed to improve crossover and mutation operations in GAs. Benchmark tests have shown that the enhanced hybrid GA is accurate, and reliable. Based on this search engine and optimisation core, a linear and nonlinear control system design automation suite is developed in a Java based platform-independent format, which can be readily available for design and design collaboration over corporate Intranets and the Internet. Since it has also made cost function unnecessary to be differentiable, hybridised indices combining time and frequency domain measurement and accommodating practical constraints can now be incorporated in the design. Such type of novel indices are proposed in the thesis and incorporated in the design suite. The Proportional plus Integral plus Derivative (PID) controller is very popular in real world control applications. The development of new PID tuning rules remains an area of active research. Many researchers, such as Åström and Hägglund, Ho, Zhuang and Atherton, have suggested many methods. However, their methods still suffer from poor load disturbance rejection, poor stability or shutting of the derivative control etc. In this thesis, Systematic and batch optimisation of PID controllers to meet practical requirements is achieved using the developed design automation suite. A novel cost function is designed to take disturbance rejection, stability in terms of gain and phase margins and other specifications into account in-the same time. Comparisons made with Ho's method confirm that the derivative action can play an important role to improve load disturbance rejection yet maintaining the same stability margins. Comparisons made with Åström’s method confirm that the results from this thesis are superior not only in load disturbance rejection but also in terms of stability margins. Further robustness issues are addressed by extending the PID structure to a free form transfer function. This is realised by achieving design automation. Quantitative Feedback Theory (QFT), method offers a direct frequency-domain design technique for uncertain plants, which can deal non-conservatively with different types of uncertainty models and specifications. QFT design problems are often multi-modal and multi-dimensional, where loop shaping is .the most challenging part. Global solutions can hardly be obtained using analytical and convex or linear programming techniques. In addition, these types of conventional methods often impose unrealistic or unpractical assumptions and often lead to very conservative designs. In this thesis, GA-based automatic loop shaping for QFT controllers suggested by the Research Group is being furthered. A new index is developed for the design which can describe stability, load rejection and reduction of high frequency gains, which has not been achieved with existing methods. The corresponding prefilter can also be systematically designed if tracking is one of the specifications. The results from the evolutionary computing based design automation suite show that the evolutionary technique is much better than numerical methods and manual designs, i.e., 'high frequency gain' and controller order have been significantly reduced. Time domain simulations show that the designed QFT controller combined with the corresponding prefilter performs more satisfactorily.

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IBM, amongst many others, have sought to endow computer systems with selfmanagement capabilities by delegating vital functions to the software itself and proposed the Autonomic Computing model. Hence inducing the so-called self-* properties including the system's ability to be self-configuring, self-optimising, self-healing and self-protecting. Initial attempts to realise such a vision have so far mostly relied on a passive adaptation whereby Design by Contract and Event-Condition-Action (ECA) type constructs are used to regulate the target systems behaviour: When a specific event makes a certain condition true then an action is triggered which executes either within the system or on its environment Whilst, such a model works well for closed systems, its effectiveness and applicability of approach diminishes as the size and complexity of the managed system increases, necessitating frequent updates to the ECA rule set to cater for new and/or unforeseen systems' behaviour. More recent research works are now adopting the parametric adaptation model, where the events, conditions and actions may be adjusted at runtime in response to the system's observed state. Such an improved control model works well up to a point, but for large scale systems of systems, with very many component interactions, the predictability and traceability of the regulation and its impact on the whole system is intractable. The selforganising systems theory, however, offers a scaleable alternative to systems control utilising emerging behaviour, observed at a global level, resulting from the low-level interactions of the distributed components. Whereby, for instance, key signals (signs) for ECA style feedback control need no longer be recognised or understood in the context of the design time system but are defined by their relevance to the runtime system. Nonetheless this model still suffers from a usually inaccessible control model with no intrinsic meaning assigned to data extraction from the systems operation. In other words, there is no grounded definition of particular observable events occurring in the system. This condition is termed the Signal Grounding Problem. This problem cannot usually be solved by analytical or algorithmic methods, as these solutions generally require precise problem formulations and a static operating domain. Rather cognitive techniques will be needed that perform effectively to evaluate and improve performance in the presence of complex, incomplete, dynamic and evolving environments. In order to develop a specification method for scalable self-governance of autonomic systems of systems, this thesis presents a number of ways to alleviate, or circumvent, the Signal Grounding Problem through the utilisation of cognitive systems and the properties of complex systems. After reviewing the specification methods available for governance models, the Situation Calculus dialect of first order logic is described with the necessary modalities for the specification of deliberative monitoring in partially observable environments with stochastic actions. This permits a specification method that allows the depiction of system guards and norms, under central control, as well as the deliberative functions required for decentralised components to present techniques around the Signal Grounding problem, engineer emergence and generally utilise the properties of large complex systems for their own self-governance. It is shown how these large-scale behaviours may be implemented and the properties assessed and utilised by an Observer System through fully functioning implementations and simulations. The work concludes with two case studies showing how the specification would be achieved in practice: An observer based meta-system for a decision support system in medicine is described, specified and implemented up to parametric adaptation and a NASA project is described with a specification given for the interactions and cooperative behaviour that leads to scale-free connectivity, which the observer system may then utilise for a previously described efficient monitoring strategy.

Le vieillissement de la population européenne a encouragé la communauté à favoriser larecherche de solutions pour soutenir cette évolution. Dans ce contexte, plusieurs questions (liéesaux services de soins de santé et aux établissements de santé, coûteux, et à capacités limitées)doivent être abordées.Ainsi, plusieurs projets de recherche et des solutions industrielles ont été proposés pour remédier àces problèmes. La plupart de ces solutions sont basées sur l'utilisation des derniers développementstechniques en matière de TIC permettant ainsi de fournir des solutions qui améliorent le bien-êtredes personnes âgées et de garantir leur indépendance dans leurs propres espaces de vie. Lessolutions technologiques fournies doivent être garanties contre les défauts potentiels deséquipements qui peuvent conduire à l'échec des systèmes et avoir un impact sur les besoins etl'indépendance des utilisateurs.Dans ce travail, nous proposons une représentation du système d'automatisation de la maison, surla base des besoins qui consiste à fournir des solutions continues et viables et répondant auxattentes des utilisateurs (tout en assurant la disponibilité des services des systèmes).Dans cet objectif, nous proposons de développer un cadre de modélisation représentant lesystème reconfigurable domotique et permettant l'examen de l'approche de la tolérance depanne, sur la base de la définition de scénarios alternatifs (assurant la délivrance continue desservices). Dans ce workflow, nous décrivons les éléments structurels du système (décrits commedes services et composants) en vue de la modélisation conceptuelle. Des règles de transformationde modèle permettent de générer un modèle d'analyse et un modèle de comportement. Lemodèle d'analyse permet de prendre une décision à propos de la sélection des élémentsalternatifs pour remplacer les éléments défectueux. Ce modèle d'analyse est défini sur la base dela notion d'approche d’arbre de défaillances, qui adopte la probabilité d'échec descomposantes pour évaluer l’état global du système considéré. Le modèle de comportement estresponsable de la simulation de l'exécution des services du système pour assurer que les scénariosconduisent à la délivrance du système.Par ailleurs, nous proposons de définir une caractéristique permettant d’évaluer l'importanceempirique (vue par le concepteur) des composantes d'un système dans le cadre d’un servicedonné. Ensuite, nous proposons une nouvelle approche, fondée sur l'intégration du facteur del'importance dans l'approche d’arbre de défaillances pour étudier la criticité du composant, encas d'échec, ainsi que la continuité de service. Un cadre de validation expérimentale, basé surplusieurs objectifs de validation est finalement proposé pour conclure ce travail de recherche. / The ageing of the European population encouraged the community to search for solutions tosupport this evolution. In this context, several issues (related to the expensive and limited healthcare services and health facilities capacities) need to be addressed.Thus, several projects, research and industrial solutions have been proposed to address these issues.Most of these projects and industrial developments are based on the use of the latest ICT technicaldevelopments to provide solutions that ameliorate the well-being of the targeted ageing groupand to guaranty their independence in their own living spaces. The provided technologicalsolutions need to be guaranteed against potential faults which may lead to the systems failure andimpact the users’ needs and independency.In this work, we propose a home automation system representation, based on the user’s needs toprovide continuous and viable solutions that meets the users’ expectations, and ensuring theavailability of system’s services.For this goal, we propose to develop an integrated modeling framework allowing therepresentation of the home automation reconfigurable system with the consideration of a faulttolerance approach (based on the alternative definition of scenarios of system servicesdeliverance).In the proposed workflow, we describe the system structural elements (described as services andcomponents) in the design modeling view, and, we lead model transformation rules allowinggenerating an analysis model and a behavior model. The analysis model allows making a decisionabout the alternative elements selection in order to substitute the faulty elements. The analysismodel definition is based on the notion of Fault Tree Analysis approach (adopting the probabilityof events failure in order to evaluate a given system status).The behavior model is in charge of simulating the execution of the system services ensuring, thus,that the proposed scenarios lead to system services deliverance.Moreover, we propose to define an expert based feature measuring the importance of a system’scomponent within the service context. In this framework, we propose a new approach, based onthe joint integration of the importance factor into the Fault Tree Analysis approach in order to studythe criticality of the component, in case of failure, on the service continuity.We propose an experimental validation framework, based on several validation objectives toevaluate the proposed work in this research

Utiliser une interface visuo-tactile peut être une gêne lorsqu'il est nécessaire de rester mobile et conscient de son environnement. Cela s'avère particulièrement problématique en milieu hostile comme pour la commande d'un drone militaire de contact.Dans ces travaux nous faisons l'hypothèse que le geste est une modalité de commande moins contraignante puisqu'elle n'impose pas de visualiser ni de manipuler une interface physique.Ainsi, différents travaux nous ont permis de confirmer d'une part, les avantages pratiques, et d'autre part, la faisabilité technique de la commande d'un robot mobile par geste.Tout d'abord, l'étude théorique du geste a permis de construire un modèle d'interaction. Celui-ci consiste en l'activation de commandes automatiques par la réalisation de gestes sémaphoriques normalisés. Des messages sonores permettent de renseigner l'opérateur et un mécanisme de confirmation sécurise l'interaction.Ensuite, le dictionnaire des gestes à utiliser a été constitué. Pour cela, une méthodologie a été proposée et appliquée : des utilisateurs proposent puis élisent les gestes les plus pertinents.Notre modèle d'interaction et le vocabulaire gestuel ont ensuite été évalués. Une étude en laboratoire nous a permis de montrer que l'interaction gestuelle telle que proposée est simple à apprendre et utiliser et qu'elle permet de conserver une bonne conscience de l'environnement.Un système interactif complet a ensuite été développé. Son architecture a été déduite du modèle d'interaction et une brique de reconnaissance gestuelle a été mise en oeuvre. En marge des méthodes classiques, la brique proposée utilise un principe de description formelle des gestes avec une grammaire régulière.Finalement, ce système a été évalué lors de tests utilisateurs. L'évaluation par des participants militaires a confirmé notre hypothèse de la pertinence du geste pour une interaction visuellement et physiquement moins contraignante. / Using a visuo-tactil interface may be restrictive when mobility and situation awareness are required. This is particularly problematic in hostile environment as commanding a drone on a battlefield.In the work presented here, we hypothesize that gesture is a less restrictive modaility as it doesn't require to manipulate nor to look at a device.Thus we followed a user-centered approach to confirm practical advantages and technical feasibility of gestural interaction for drones.First, the theoretical study of gestures allowed us to design an interaction model. It consists on activating commands by executing standardized semaphoric gestures. Sound messages inform the user and a confirmation mechanism secure the interaction.Second, a gestural vocabulary has been built. To do so, a methodology has been proposed and used : end users elicited then elected the most appropriate gestures.Then, the interaction model and the selected gestures have been evaluated. A laboratory study showed that they are both easy to learn and use and helps situation awareness.An interactive system as then been developed. It's architecture has been deducted from our interaction model and a gesture recognizer as been buit. Different from usual methods, the recognizer we proposed is based on formal description of gestures using regular expressions.Finaly, we conducted a user testing of the proposed system. The evaluation by end-users confirmed our hypothesis that gestures are a modality less distractive both visualy and physicaly.

Το αντικείμενο της παρούσας διπλωματικής εργασίας αφορά την ανάλυση και τον έλεγχο κυβερνοφυσικών δικτυωμένων δυναμικών συστημάτων. Ειδικότερα, μελετώνται γραμμικά χρονικά αμετάβλητα συστήματα μίας εισόδου με περιορισμούς τόσο στην είσοδο όσο και στο διάνυσμα καταστατικών μεταβλητών και προτείνονται στρατηγικές ανταγωνιστικού ελέγχου. Συγκεκριμένα, ένας βέλτιστος ελεγκτής εξασφαλίζει θετική αμεταβλητότητα ενός φραγμένου κυρτού πολυεδρικού συνόλου ως προς το σύστημα και ταυτόχρονα σύγκλιση της τροχιάς του διανύσματος κατάστασης στο μηδέν το συντομότερο δυνατό. Υποθέτουμε ότι ένας «ανταγωνιστής » ελεγκτής επιτυγχάνει κατά διαστήματα να αναλάβει τον έλεγχο του συστήματος και αποστέλλει μέσω του δικτύου εσφαλμένα σήματα εισόδου στοχεύοντας να οδηγήσει το διάνυσμα κατάστασης εκτός του πολυεδρικού συνόλου το συντομότερο δυνατό. Προσομοιώσεις καταδεικνύουν ότι το διακοπτικό φαινόμενο που ανακύπτει από τη διαδοχική εφαρμογή των δύο παραπάνω ελεγκτών προκαλεί μία περιοδική τροχιά του διανύσματος κατάστασης. Τα θεωρητικά εργαλεία που χρησιμοποιήθηκαν για την εξαγωγή των αποτελεσμάτων προέρχονται από τη θεωρία ευστάθειας Lyapunov και τη θεωρία αμετάβλητων συνόλων. / This thesis addresses the analysis and control of networked cyber-physical dynamical systems. We are mostly concerned with the study of linear, time-invariant systems with single input. The systems evolve in the discrete time and are subject to both state and input constraints and a certain number of adversary control strategies are proposed. A time-optimal control law guarantees positive invariance of a bounded convex polyhedral set with respect to the given system, while contracting the state space vector to the origin. At times, an adversary controller succeeds in gaining control of the system and sends false control commands attempting to lead the state vector outside the polyhedral set at the maximum admissible rate. Simulation studies highlight that consecutively applying the above control laws results in a periodic motion of the state vector. The theoretic tools used to obtain our conclusions associate with Lyapunov stability and set theory.

La téléopération ouvre des possibilité nouvelles d'interaction avec le micro-monde. Avec des systèmes adaptés il devient possible de manipuler des éléments aux échelles microscopiques. L'ajout d'un retour haptique apporte une information supplémentaire nécessaire à une interaction naturelle. Cette thèse aborde la problématique de la conception d'une chaîne de téléopération haptique par la conception de ses éléments clefs. La première partie décrit l'optimisation de l'interface haptique à un degré de liberté haute fidelité issue des précédents travaux du laboratoire. Un premier travail augmente la précision des efforts produits. Cette amélioration est liée à une optimisation de la mesure de la vitesse de l'interface à des fréquences d’échantillonnage élevées. Un second point traite de la validation et quantification précise des forces de l'interface. La deuxième partie décrit deux nouveaux capteurs de force conçu spécifiquement pour les interactions avec le micro-monde. Ces fonctionnent sur le même principe de mesure par compensation. Deux approches sont suivies pour augmenter les fréquences des forces mesurable par le capteur. La première s'attache à réduire la masse en concevant un nouveau capteur à l'échelle micrométrique avec des technologies MEMS. Une deuxième approche modifie la conception du capteur et supprime la raideur dans le guidage. La troisième partie décrit la conception d'une nouvelle interface haptique à plusieurs degrés de liberté. Les éléments clefs de sa conception sont l'utilisation d'un palier à air, pour un guidage sans frottement, et de moteurs linéaires à induction, pour une inertie réduite. / Teleoperation opens up new possibilities for interaction with the micro-world. Adequate systems make it possible for human to manipulate elements on microscopic scales. An added haptic feedback provides information crucial for a natural interaction. A bilateral coupling between the subsystems offers the best haptic transparency. This thesis addresses the design of a complete haptic teleoperation chain by focusing on its key elements. Three parts are detailed: The first part describes improvements of the high fidelity one degree of freedom haptic interface designed previously. First, the precision of the forces produced is improved. This improvement is related to the measurement of the motor velocity at high sampling frequencies. Then, the device is precisely caracterized. The second part describes the design of two new force sensors designed specifically for interactions with the micro-world. The forces are measured by compensation. Two approach are observed to expand the frequencies of forces measurable by the sensors. First approach try to reduce the mass, a new sensor on a micrometric scale is built with MEMS technologies. The second approach offer a new design of the sensor. In particular, the stiffness in the guidance is removed. The third part describes the design of a new haptic interface with multiple degrees of freedom. This interface combines the performances of the one degree of freedom interface with a 2D configuration. The key elements of its design are the an air bearing for frictionless guidance and linear induction motors for reduced inertia.