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Conception d'une nouvelle luge pour améliorer la performance d'un fondeur paralympiqueLeblanc-Lebeau, Marie-Pierre January 2009 (has links)
Ce mémoire présente le processus de conception d'une nouvelle luge pour le fondeur paralympique.Ce nouvel équipement vise à améliorer les performances de l'athlète pratiquant le ski de fond sur luge. L'athlète en ski de fond paralympique est classé selon la gravité de son handicap des membres inférieurs et le sport est régi par les règlements établis par le Comité international paralympique (IPC) . L'athlète utilise des bâtons, des skis et une luge. Les objectifs de conception ont été établis avec l'aide des entraîneurs et des athlètes. Ils consistent à améliorer la performance du skieur durant les virages, à permettre aux skis de s'adapter plus facilement aux défauts de la piste, à positionner l'athlète à genou et à concevoir un siège permettant un meilleur couplage entre l'athlète et la luge. La conception de la luge présente différents systèmes répondant à ces objectifs : un système de génération de force centripète, un système d'angulation des skis, un châssis et un siège. La validation de ces systèmes constituant la luge a été faite soit en laboratoire soit sur le terrain. Le prototype final servant à la majorité des tests de validation a été conçu pour une athlète spécifique, soit Colette Bourgonje.
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Thermal-Fluid Dynamic Model of Luge SteelsStell, Brandon 01 December 2017 (has links)
Luge is an Olympic sport in which athletes ride feet-first on sleds down an ice-covered track. Competitors spring from the starting position and accelerate their sled by paddling with spiked gloves against the ice surface. Once the Luger leaves the starting section, their downhill motion is solely propelled by the effects of gravity. Athletes compete, one after the other, for the fastest time. Runs can differ by as little as a thousandth of a second, meaning that every minor sled adjustment, change of line choice, and shift of body position is critical. In the past, the sport of Luge has progressed through a series of steps involving trial and error, where changes to the sled and strategy rely more on intuition and race results, rather than in-depth, mathematical analysis. In an effort to try and improve track times for the US Olympic Luge team, a track and driver model is in development in order to simulate a sled going down the track. By doing this, the hope is to be able to pinpoint areas of possible improvement to the sled and see how adjustments can affect the optimum line down the track. A part of this model, which is the focus of the following paper, is the inclusion of an analysis to identify the frictional relationship between the ice surface and the steels of the sled. The model created of the ice-steel interaction was put in the form of a function file, which includes inputs of down force, ice temperature, sled velocity, and steel geometry. Creation of this model and completion of a set of parametric studies allowed for further understanding the interaction between the sled steels and ice surface, specifically applying to the sport of Luge. The model predicts for lower temperatures that at slower sled velocities the coefficient of friction is greater compared to faster sled velocities. This relationship inverts as the ice temperature moves closer to the melting temperature. A sharper steel edge radius was found to be beneficial in lowering the coefficient of friction at lower sled velocities. The sharp edge radius friction benefit decreases as the sled speed increases and is predicted to actually increase friction slightly compared to duller blades at greater velocities. A flat as possible rocker radius lowers friction at all sled velocities, as well as in banked turns where two contact patches are possible. On curves, the pressure on the steel is increased due to the effects of centripetal accelerations. A 1 g versus 5 g normal loading, experienced on the last turns of the track, increases the coefficient of friction on the blade, but also increases the allowable lateral force on the sled before side slip occurs. Understanding the relationships of these parameters, along with the information that may be gained from the driver model, may prove to be useful in choosing optimum sled characteristics and line choice.
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