The quality of electric power has been a constant topic of study, mainly because inherent problems to it can bring great economic losses in industrial processes. Among the factors that affect power quality, those related to transients originated from capacitor bank switching in the primary distribution systems must be highlighted. In this thesis, the characteristics of the transients resulting from the switching of utility capacitor banks are analyzed, as well as factors that influence there intensities. A practical application of synchronous closing to reduce capacitor bank switching transients is presented. A model that represents a real distribution system 12.47kV from Shelbyville sub-station was built and simulated using MATLAB/SIMULINK software for purposes of this study. A spectral analysis of voltage and current waves is made to extract the acceptable capacitor switching times by observing the transient over-voltages and, harmonic components. An algorithm is developed for practical implementation of zero-crossing technique by taking the results obtained from the SIMULINK model.

Driving has become a very common activity for most of the people around the world today. People are becoming more and more dependent on vehicles, contributing to the growth of automotive industry. New vehicles are released regularly into the market in order to meet the high demand. With the increase in demand, the importance of vehicle testing has also increased by many folds. Besides testing new vehicles for their performance prediction, existing vehicles also need to be tested in order to check their compliance to safety standards. Drive Cycles that have been traditionally defined as velocity over time profiles are used as vehicle testing beds. The need for re-defining drive cycles is demonstrated through the high deviations between the predicted and the actual performance values. As such, a new approach for defining automotive drive cycles, Journey Mapping, is proposed. Journey Mapping defines a drive cycle more realistically as the journey of a particular vehicle from an origin to the destination, which during its journey is influenced by various conditions such as weather, terrain, traffic, driver behavior, road , vehicle and aerodynamic. This concept of Journey Mapping has been implemented using AMESim for a Ford Focus Electric 2012. Journey Mapping was seen to predict its energy consumption with about 5% error; whereas, the error was about 13% when it was tested against the US06 cycle, which provided the most accurate results out of the various traditional drive cycles used for testing for the selected scope. / Thesis / Master of Applied Science (MASc)

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Le corps humain a toujours été une source d’inspiration pour les ingénieurs et les scientifiques de tous les domaines dans le monde entier. L’un des sujets les plus intéressants de la dernière décennie a été les robots humanoïdes. Les robots humanoïdes représentent les systèmes robotiques les plus complexes. Ils offrent une plus grande mobilité dans les terrains accidentés et non structurés que les véhicules à roues normaux. À l’avenir, les robots humanoïdes devraient être employés pour une variété de tâches dangereuses dans des domaines tels que les opérations de sauvetage, l’assistance aux personnes âgées, l’éducation et le déminage humanitaire. Le travail réalisé dans cette thèse est réalisé sur le robot hydraulique humanoïde HYDROïD, un humanoïde à commande hydraulique avec 52 degrés de liberté actifs, conçu pour exécuter des tâches très dynamiques comme la marche, la course et le saut. robot puisque les actionneurs hydrauliques ont un excellent rapport poids/puissance et absorbent naturellement les pics de force d’impact lors des différentes activités. L'objectif de cette thèse est de contribuer au développement des mécanismes robotiques de la cheville et du genou avec une dynamique élevée. Un nouveau mécanisme de cheville est développé afin de pallier les inconvénients des performances réalisées avec l’ancien mécanisme de cheville d'origine. Des taux de fuite et de frottement plus faibles sont obtenus en plus d’une optimisation de pression pour les articulations de la cheville. De plus, une nouvelle solution pour optimiser le poids des actionneurs hydrauliques est appliquée sur le mécanisme du genou du robot.Une telle solution comprend l’utilisation de la technologie des matériaux composites légers pour atteindre un poids et une performance optimisés pour le joint. Afin d’appliquer des méthodologies de contrôle sur les mécanismes de la cheville et du genou, un modèle géométrique inverse pour les deux mécanismes est présenté. Le contrôle de position est utilisé pour contrôler les angles des articulations de la cheville et les mécanismes du genou. Enfin, les conclusions et les perspectives d’avenir sont présentées dans le dernier chapitre. / Human body has always been an inspiration for engineers and scientists from all fields all over the world. One of the most interesting topics in the last decade was humanoid robots. Humanoid robots represent the most complex robotic systems. They provide greater mobility in rough and unstructured terrain than the normal wheeled vehicles. In the future, humanoid robots are expected to be employed for a variety of dangerous tasks in fields like rescue operations, assisting elderly people, education and humanitarian demining. The work achieved in this dissertation is performed on the humanoid hydraulic robot HYDROïD. It is hydraulically actuated humanoid featuring 52 active degrees of freedom and is designed to perform highly dynamic tasks like walking, running and jumping. Hydraulic power was chosen for this robot since hydraulic actuators have an excellent power to weight ratio and naturally absorb impact force peaks during different activities. The objective of this dissertation is to contribute toward the development of ahighly dynamic robotic ankle and knee mechanisms. A new ankle mechanism islooked for in order to tackle the drawbacks raised by the performances achievedwith the original old ankle mechanism. Lower leakage and friction rates areachieved in addition to a pressure optimization for the ankle joints. Moreover, anew solution for optimizing the weight of hydraulic actuators is applied on theknee mechanism of the robot. Such solution includes the usage of light compositematerial technology to achieve optimized weight and performance for the joint.In order to apply control methodologies on the ankle and knee mechanisms,inverse geometrical model for the both mechanism are presented. Position controlis used to control the joints angles of the ankle and the knee mechanisms. Finally,the conclusions and the future perspectives are presented in the last chapter.

Smart polymers are stimuli-responsive materials that undergo reversible and large changes of the material properties as a consequence of small environmental variations. Their light weight, biocompatibility, adaptability, mechanical strength and environment-friendly properties make them suitable for a wide range of applications, such as actuators, sensors and energy transducers. Despite their very interesting properties, there are still many problems which need to be solved. In particular, there is a high demand by the scientific community to develop advanced theoretical models which aim at understanding the complex and unclear phenomena occurring in smart polymers. In the present thesis, an innovative multiphysics electro-chemo-hydro-mechanical (ECHM) model is formulated within the framework of continuum mechanics. The proposed model assumes the solvent-ion-polymer mixture as a continuum homogenized body and takes into account four different physical fields, namely: (i) the electrical field, (ii) the chemical field related to the ion transport, (iii) the chemical field related to the water/solvent transport, and (iv) the mechanical field within the framework of large deformations. Couplings terms are derived at the constitutive level among the involved physical fields and allow to model a key aspect of smart polymers, i.e. the capability of transducing energy from one form to another. Reduced versions of the ECHM model are used to investigate, numerically and analytically, three particular problems involving smart polymers, namely: (i) the chemical reactions occurring at the interface between the polymer membrane and the electrodes of electrochemical cells, (ii) the electro-chemo-mechanical state of a single polymeric membrane within a stack of membranes, and (iii) the swelling/shrinking process of constrained and stressed polymer gels. The performed investigation confirm that the ECHM model and its reduced versions are capable of describing the complex multiphysics behavior of smart polymers. The current research improves the theoretical knowledge concerning the behavior of smart polymers and gives further contributions in literature. Starting from the outcomes of the proposed research, many interesting extensions can be potentially developed in order to address very important topics as, for example, fatigue in polymers. / Smarte Polymere sind stimulierbare Materialien, die, verursacht durch die Änderung ihrer Umgebung, eine reversible und große Änderung ihrer materiellen Eigenschaften erfahren. Ihr leichtes Gewicht, ihre Biokompatibilität, ihr Anpassungsvermögen, ihre mechanische Beanspruchbarkeit und ihre umgebungsfreundlichen Eigenschaften machen sie attraktiv für weite Anwendungsbereiche, z. B. als Aktoren, Sensoren oder Energiewandler. Trotz ihrer exzellenten Eigenschaften gibt es noch viele Probleme, die gelöst werden müssen. Insbesondere die Nachfrage nach fortgeschrittenen theoretischen Modellen mit dem Ziel die komplexen physikalischen Phänomene zu beschreiben, die in smarten Polymeren ablaufen, ist sehr hoch. In der eingereichten Doktorarbeit, wird ein elektro-chemo-hydro-mechanisches (ECHM) Modell basierend auf der Kontinuumsmechanik vorgestellt. In dem dargelegten Modell wird die Mischung aus Lösungsmittel, Ionen und Polymer als homogenisiertes Kontinuum betrachtet, wobei vier verschiedene physikalische Felder berücksichtigt werden: (i) das elektrische Feld, (ii) das auf den Ionentransport bezogene chemische Feld (iii) das auf den Wasser- bzw. den Lösungsmitteltransport bezogene chemische Feld und (iv) das mechanische Feld unter der Berücksichtigung von großen Deformationen. Kopplungsterme werden auf konstitutiver Ebene aus den beteiligten physikalischen Feldern abgeleitet. Die elektro-chemo-mechanische Kopplung erlaubt die Modellierung einer der wesentlichen Eigenschaften smarter Polymere, nämlich die Fähigkeit zur Umwandlung der verschiedenen Energieformen. Drei spezielle Problemstellungen von smarten Polymeren, wurden numerisch und analytisch auf Grundlage reduzierter Varianten des ECHM-Modells untersucht: (i) die auftretenden chemischen Reaktionen an der materiellen Grenzfläche zwischen Polymermembran und den Elektroden der elektrochemischen Zelle, (ii) das elektro-chemo-mechanische Verhalten einer einzelnen Polymer-membran in einem Membranstapel und (iii) der Quellungs- bzw. Entquellprozess von vorgespannten Polymergelen. Die durchgeführten Untersuchungen bestätigen die Anwendbarkeit des ECHM-Modells und seinen reduzierten Varianten zur Beschreibung des komplexen physikalischen Verhaltens von smarten Polymeren. Die dargelegte Forschung verbessert das theoretische Verständnis hinsichtlich des Verhaltens von smarten Polymeren und leistet einen Beitrag zum aktuellen Stand der Wissenschaft. Auf den Resultaten der dargelegten Forschung basierend, können viele interessante Erweiterungen gemacht werden, welche sich auf wichtige Themengebiete, wie z. B. die Ermüdung von Polymeren, beziehen.

Cette thèse s’inscrit dans le domaine de la localisation de défauts de type «soft» dans les Circuits Intégrés (CI) analogiques et mixtes à l’aide des techniques dynamiques de stimulation laser en faible perturbation. Les résultats obtenus à l’aide de ces techniques sont très complexes à analyser dans le cas des CI analogiques et mixtes. Ce travail porte ainsi particulièrement sur le développement d’une méthodologie facilitant l’analyse des cartographies laser. Cette méthodologie est basée sur la comparaison de résultats de simulations électriques de l’interaction faisceau laser-CI avec des résultats expérimentaux (cartographies laser). L’influence des phénomènes thermique et photoélectrique sur les CI (niveau transistor) a été modélisée et simulée. La méthodologie a été validée tout d’abord sur des structures de tests simples avant d’être utilisée sur des CI complexes que l’on trouve dans le commerce. / This thesis deals with Soft failure localization in the analog and mixed mode Integrated Circuits (ICs) by means of Dynamic Laser Stimulation techniques (DLS). The results obtained using these techniques are very complex to analyze in the case of analog and mixed ICs. In this work we develop a methodology which facilitates the analysis of the laser mapping. This methodology consists on combining the experimental results (laser mapping) with the electrical simulations of laser stimulation impact on the device. The influence of photoelectric and thermal phenomena on the IC (transistor level) has been modeled and simulated. The methodology has been validated primarily on test structures before being used on complex Freescale ICs existing in commerce.