Space Shuttle | EPFL Graph Search

The Space Shuttle is a retired, partially reusable low Earth orbital spacecraft system operated from 1981 to 2011 by the U.S. National Aeronautics and Space Administration (NASA) as part of the Space Shuttle program. Its official program name was Space Transportation System (STS), taken from a 1969 plan for a system of reusable spacecraft where it was the only item funded for development. The first (STS-1) of four orbital test flights occurred in 1981, leading to operational flights (STS-5) beginning in 1982. Five complete Space Shuttle orbiter vehicles were built and flown on a total of 135 missions from 1981 to 2011. They launched from the Kennedy Space Center (KSC) in Florida. Operational missions launched numerous satellites, interplanetary probes, and the Hubble Space Telescope (HST), conducted science experiments in orbit, participated in the Shuttle-Mir program with Russia, and participated in the construction and servicing of the International Space Station (ISS). The Space

Reconquérir les bords de Marne: un complexe multi-fonctionnel pour un parcours de lieux et de liens (Région parisienne, France)

Aurélie Harlin, Charlotte Thietart

De Paris intra-muros à Paris extra-muros, la ligne de Vincennes participe de la constitution d'une hiérarchie entre le centre et les bords de l'Est parisien. Le long de son tracé, topographie, eau, espaces verts et agricoles, réseaux de mobilité amènent un nouveau regard sur la métropole dans leur capacité à être reliés. Suivant une exploration de possibles dispositifs pour un continuum intra-extra muros, ils confèrent une épaisseur à la ligne de Vincennes. Sur un de ses tronçons ferrés, le périmètre de notre intervention cible une zone de confluence où toutes ces préoccupations se retrouvent dans un concentré spatial à forte richesse paysagère: le Bois de Vincennes, la Marne et ses berges, l'île Fanac, le canal de Polangis. A partir de deux gares et dans un souci de connecter ces éléments du territoire, une série d'événements offre une redécouverte du paysage donnant naissance à un parcours densifié, revitalisé et poreux. Susceptible d'être le point catalyseur de cette démarche, le site, localisé le long des berges et d'un axe historique, incarne la reconquête des bords de Marne comme lieu des possibles du loisir. Afin d'attirer les gens à l'extérieur de Paris, un complexe multi-fonctionnel, alliant culture et sport, vise à propager un ensemble de conditions nouvelles afin de nourrir d'anciennes traces aujourd'hui épuisées. Dans un rapport réciproque avec les éléments du territoire, ce projet insuffle une énergie nouvelle révélant au promeneur l'épaisseur du site.

2011

Méthodologie de conception et optimisation d'actionneurs intégrés sans fer

Igor Stefanini

The growing demand for new technologies in several fields : recreation, medicine, transport, telecommunications and the space industry, etc. is increasingly related to the field of the management, transformation and use of electric power. In this domain, the development of no-ferromagnetic integrated electromechanical actuators finds wide application and thus implies an usefulness over a large diversity of geometries. The absence of ferromagnetic materials does not allow for quick determination of an equivalent electromagnetic circuit for this type of actuator. The interaction of the magnetic induction fields produces phenomenas like the skin effect and the proximity effect which degrade its performance. In such circumstances, there is a compromise to be made between the analytical model's complexity and the precision of the results. Often, a modeling based on numerical approaches, which uses finite element methods, is the best adapted approach. Nevertheless, this type of analysis requires much experience and in particular, the parameterization of the actuator specifications and the exploitation of such a model in the optimized design is not very practical and requires considerable computing time. The use of discretized analytical models constitutes a good compromise between the degree of complexity and the model's correspondence to reality. Accordingly, in this thesis, we propose a suite of discretized analytical models allowing for the design and the optimization of this type of actuator. The development of a general rule to determine the optimal discretization step allows an arbitration between computing time, degree of complexity, and the precision of the results. The identification and the validation of the analytical models describing the skin and proximity effects have made it possible to improve the computation of self-inductance and winding resistance. The development of a design and optimization methodology for this type of actuator permits each application to be optimized in a systematic and efficient way, by proposing one or more possible solutions with their advantages and their disadvantages. Two distinct applications were conceived and optimized adopting this design methodology : the Montrac® system and the Iglus® system. In the Montrac® project, it was a question of modifying the power system of a modular assembly line. This system is composed of a fixed track with motorized shuttles for use in a clean room environment. The replacement of the electrical contacts by a contactless energy transmission system was dimensioned and optimized in order to guarantee an operation compatible with the requirements of the above mentioned environment. In the Iglus® project, a subcutaneous biomedical actuator for glycemic level detection, with the aim of measuring the glucose level of diabetes patients was optimized. The measurements and results from these two applications, made it possible to confirm the validity of the models expounded in this thesis.

EPFL2006

Méthodologie de conception et optimisation d'actionneurs intégrés sans fer

Igor Stefanini

EPFL2006