Дисертації: "Automobiles Radiators Design and construction"

1

Staples, Judd W. "Optimizing the allocation of resources during preliminary automobile design." Thesis, Georgia Institute of Technology, 1994. http://hdl.handle.net/1853/17975.

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2

de, Vos Neil. "Design of a new protective isolating side-door : a virtual model to simulate ingress and egress motion for micro-mobility vehicles." Thesis, Cape Peninsula University of Technology, 2016. http://hdl.handle.net/20.500.11838/2468.

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Thesis (MTech (Industrial Design))--Cape Peninsula University of Technology, 2016.
This paper is positioned within the broader context of public transportation systems, with specific focus on the development of urban micro first and last mile mobility solutions, and what it could mean for individuals and the economy. Globally, urban problems such as traffic congestion, poor public transport integration, and carbon emissions are forcing us to rethink traditional means of transport. Large fossil-fuelled vehicles and limited public transport infrastructure characterize South Africa’s transport market. Despite the growth in car use, public transport and walking are still the predominant “lifeline” forms of mobility for the vast majority of South Africans in order to access work, schools and services. Moreover, the lack of public transport services in key economic corridors and rural areas of South Africa, the role of the metered taxi industry which is currently effectively limited to serving only the needs of the tourist market due to high charging regimes, and finally, the absence of an effective inner city transport system endorses the lack of first and last mile transportation solutions, and the integration thereof with other transport mediums. This adds to the conflict commuter’s face on a daily basis in obtaining a seamless distribution of transport services. 80% of trips in urban areas are less than 3km, placing urban micro mobility vehicles in an ideal position as a solution to transportation. This describes the investigation conducted into micro-mobility trends within South Africa to identify a key mode of transport that would comply with the stated requirements, and allow accessibility to commuters within the city and to the surrounding communities. In 2014, Mellowcabs, which are electric public transport vehicles that provide first and last mile transport services, was identified as a promising candidate within the local micro-mobility vehicle context. They were in need of a design input for their immediate next requirement, which thus describes the development of a good protective side door system that would isolate passengers in adverse weather conditions, whilst similarly affording comfort and safety features found in normal passenger vehicles. The design process is focused on creating a new side door, however, at the same time the product should be, elegant, smart, fashionable, comfortable, economical, maneuverable and safe. In addition, the virtual product lifecycle management tool, CATIA, allows the design team to get feedback in terms of physical-based data that correspond to how the door could hinder the passengers interaction while they ingress and egress the vehicle. This enables us to try various designs to perform a comparative study without building a single physical prototype.

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3

Zhu, Min. "Design of automotive joints : using optimization to translate performance criteria to physical design parameters /." Diss., This resource online, 1994. http://scholar.lib.vt.edu/theses/available/etd-06062008-165515/.

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4

Zhao, Gui Quan. "Design, control and experimental testing of intelligent variable dual-fuel automotive engines." Thesis, University of Macau, 2017. http://umaclib3.umac.mo/record=b3691635.

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5

Cawood, Gareth James. "Design of a low-cost autonomous guided cart for material handling." Thesis, Nelson Mandela Metropolitan University, 2015.

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This dissertation covers the design and manufacture of an autonomous guided cart (AGC) for use in the material handling industry. General Motors South Africa (GMSA) requires a low-cost AGC for use in their Struandale plant. A budget of R35 000 per unit was proposed. The researcher, in collaboration with staff at GM, compiled a list of engineering requirements for the AGC. After research into the unique problems of the project, an examination of a previous design attempt by staff of GM Thailand, the researcher developed a new design, the subject of this report. Different solutions for each design problem were investigated before the design was finalised. A three-wheeled vehicle was designed making use of two motors in a differential-drive setup to control motion. Navigation is via a line-following mechanism, using an induction sensor-array in conjunction with a pre-laid metallic strip. To aid the design, the system was modelled to understand the different control elements at play. The researcher developed software for several aspects of the design: for the PLC controlling the system and motors; for a microcontroller that communicates with the PLC and a wireless module; for a computer server that communicates with a second wireless device, receiving information from the PLC; and a web interface to view this information. These form the SCADA integration of the project. The final product meets the GMSA specifications. It is a robot capable of towing a trolley of mass not exceeding 350 kg. While the robot is able to navigate a pre-laid route, it cannot reliably stop at marked locations. It is possible to monitor the system via a web-interface. The robot is capable of operating for an entire 8-hour shift before the batteries need to be recharged. The total cost of the prototype was R26 340.

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6

Brackin, Margueritte Patricia Dodd. "Translating the voice of the customer into preliminary design specifications." Diss., Georgia Institute of Technology, 1997. http://hdl.handle.net/1853/17936.

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7

Buchmann, Macro. "Advanced monitoring system for bolted connections in vehicle construction." Thesis, Nelson Mandela Metropolitan University, 2010. http://hdl.handle.net/10948/1417.

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Bolted connections where used from the beginning of vehicle construction for joining two or more parts. The reliability of bolted connections is still a major problem. The objective of this research thesis is focused on an advanced monitoring system for bolted connections in vehicle construction. A mechanical “vibrating test bench”, which was developed by the aeronautical engineer Mr. Junkers, is being adapted, to suite the requirements of the automotive industry. It is designed according to DIN 65151 standards. The bolted connection is tightened to a specific torque to achieve the required preload forces and then exposed to an oscillating elastic shear force. The preload force and their loss are measured in relation to the number of load cycles. The ideal locking mechanism would be, if no settling occurs. Realistic in practice is the remaining of a sufficient preload force which doesn’t decry with time. The aim of this thesis is, to gain knowledge that will assist in the future control of the bolt locking procedure. The test bench can be used to verify the clamping capability of a bolted connection. With the dynamic computer-aided test system it will also be possible to test critical bolted joints and their safety, which reduces the probability of costly product recalls, or even severe cases of failure.

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8

Headley, F. Anthony Jr. "Performance limitations of an ejector heat pump." Thesis, Georgia Institute of Technology, 1991. http://hdl.handle.net/1853/20290.

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9

Rose, Garrett. "Electrical subsystem for Shell eco-marathon urban concept battery powered vehicle." Thesis, Cape Peninsula University of Technology, 2018. http://hdl.handle.net/20.500.11838/2814.

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Thesis (Master of Engineering in Electrical Engineering)--Cape Peninsula University of Technology, 2018.
The purpose of this paper was to design and develop an electrical power train for an Urban Concept electric vehicle geared to complete the Shell Eco-Marathon Africa in 2019. Various technologies which make up the electrical drive train of an electrical vehicle were also reviewed which include the battery pack, the battery management system, the motors, the motor management system and the human interface. Upon completion of this, the various topologies best suited for this project were selected, designed, constructed and developed. Two motors were re-designed and constructed for this vehicle and the motor drive was also constructed to control these motors. A Lithium-Ion battery pack was constructed and developed to drive the motors and an off-the-shelf battery management system was purchased and developed to suit the requirements for the Shell Eco- Marathon competition rules. A human interface was also developed in order for the driver to see various parameters of the electric vehicle defined by the Shell Eco-Marathon competition rules. After each component of the drive train was constructed, they underwent various testing procedures to determine the efficiency of each individual component and the overall efficiency for the complete drive train of this electric vehicle was ascertained. The Product Lifecycle Management Competency Centre group developed the chassis for this vehicle. For this reason, only the electric subsystems were evaluated and a simulation was completed of the complete drive train. After the complete drive train was constructed and all the individual subsystems evaluated and simulated, a vehicle with an overall efficiency of about sixty percent was expected and the completed drive train should be adequate enough to complete the entire Shell Eco-Marathon Africa circuit.

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10

Tam, Kuok San. "Design and analysis of an electro-hydro-mechanical variable valve actuator for four-stroke automobile engines." Thesis, University of Macau, 2011. http://umaclib3.umac.mo/record=b2493685.

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11

Coetzee, Gerhardus Johannes. "Universal design in automobiles : an investigation into simulators for differently abled drivers." Thesis, Cape Peninsula University of Technology, 2016. http://hdl.handle.net/20.500.11838/2469.

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Thesis (MTech (Industrial Design))--Cape Peninsula University of Technology, 2016.
Simulators are used for many different purposes, among them physical rehabilitation and the training of differently abled learner-drivers. In South Africa, however, the extent of the latter type of simulators is limited to paraplegic learner-drivers only. The reason is that locally sourcing the necessary equipment to adapt commercial simulators for the training of differently abled learner-drivers presents a problem. The concept of Universal Design stipulates that as many individuals as possible should be able to use a particular product. Consequently, a simulator for differently abled learner-drivers should accommodate as many such persons as possible. However, applying Universal Design in the area of design researched for the present dissertation adds further complexity due to the unique nature of the physical limitations experienced by individuals. A differently abled driver puts an extreme constraint on the design of a product - and becomes a limiting user. Nevertheless, this dissertation adopts a Universal Design approach to investigate the possibility of designing such a simulator in South Africa, as well as its viability. A limiting user was included in the research to represent the bigger differently abled community. Field research was carried out by implementing a Participatory Design process. Furthermore, a team was selected according to a Meta-Design mind-set, including professionals from engineering, clinical psychology and occupational therapy. The leader and researcher was an industrial designer.

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12

Amezquita, Tony. "Lean remanufacturing in the automotive industry." Thesis, Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/23166.

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13

Khoudeir, Riad Truchot Patrick. "L'amélioration de l'habitabilité automobile de demain l'application des principes de la construction architecturale de la maison dans la conception de l'habitacle des concepts-cars /." S. l. : S. n, 2007. http://www.scd.inpl-nancy.fr/theses/2007_KHOUDEIR_R.pdf.

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14

Loyer, Bruno. "Conception fonctionnelle robuste par optimisation multicritère de systèmes de suspension automobile passifs et semi-actifs." Ecully, Ecole centrale de Lyon, 2009. http://bibli.ec-lyon.fr/exl-doc/TH_T2152_bloyer.pdf.

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La conception de systèmes équipant les véhicules automobiles est de plus en plus contrainte, tant pour des questions de concurrence et de réduction des coûts et délais de développement qu’en raison d’évolutions techniques et réglementaires des produits (amélioration généralisée de la qualité et de la sécurité, introduction de prestations nouvelles, etc. ). Dans un tel contexte, la satisfaction du client impose aux constructeurs de prendre en compte, très tôt dans les projets, la robustesse des véhicules qu’ils proposent, c’est-à-dire la stabilité des niveaux de performances annoncés vis-à-vis des incertitudes dues à la variabilité des conditions d’utilisation, aux dispersions de fabrication (géométrie, assemblage ou propriétés mécaniques) ou encore, au vieillissement des composants. En plus du grand nombre de paramètres, de contraintes et de prestations à considérer, cette conception robuste, qui suppose la simulation numérique de ces incertitudes, impose de recourir à une stratégie de conception « à coût faible et à coup sûr », hiérarchisée, s’intégrant parfaitement dans le contexte du cycle en V de l’Ingénierie Système. La démarche First Design, mise en oeuvre dans de précédents travaux est une stratégie possible. L’objectif de cette thèse est d’en étendre certains aspects et de l’appliquer à l’optimisation fonctionnelle robuste de niveau 5 (dans le jargon Renault) des systèmes définissant la Liaison au sol des véhicules automobiles : trains roulants et variables fondamentales des pneumatiques. Il s’agit donc de développer les modèles ainsi que les outils d’optimisation et d’aide à la décision associés qui permettront de définir une procédure globale et fiable de spécification de ces systèmes, intégrant de façon quantifiée cette notion de robustesse. L’approche utilisée, fondée notamment sur des modèles physiques simplifiés et des estimateurs de sensibilité directement intégrés aux algorithmes d’optimisation, a amélioré de façon significative la robustesse des solutions et permis de mettre en évidence les gains associés à la prise en compte en amont de la présence de systèmes pilotés
In the last few years, extreme competition between car manufacturers led to higher quality and safety standards, and reduction of costs and delays in product development. Together with technical and regulation evolutions, this caused the design of vehicle subsystems to become more and more constraint. In such a context, designers who want to meet customer requirements have to take the robustness of their products into account, even at early stages of the design process. Indeed, due to the variability of the product itself (in terms of geometrical or mechanical properties, of assembly or ageing of components), or its operating conditions, the stability of the announced performance levels has to be specified and guaranteed, in presence of uncertainty. In addition to high numbers of design variables, constraints and objectives, this ‘robust design’ requires a numerical simulation of this uncertainty. Therefore, a reliable, hierarchized and computationally efficient methodology that fully complies with the V-diagram of Systems Engineering is needed. The First Design methodology is one possible approach. It was successfully used in previous works. The aim of the present thesis is to extend some of its features, and apply it to the robust optimization of the ‘level 5’ functional architecture of automotive suspension systems: front and rear axle design parameters and primary variables of the tires. For this purpose, models and associated tools for optimization and computer-aided decision have to be developed in order to define a global and reliable procedure for the specification of these systems, with a fully integrated and quantified notion of the robustness. The proposed technique, partly relying on physical simplified models and sensitivity estimators directly integrated in the used optimization algorithms, improved the robustness of the solutions significantly, and emphasized the performance gains achieved by taking the presence of semi-active components into account, at early phases of the project

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15

Lee, Jong-Nyun. "Design sensitivity analysis of multibody systems with special reference to four-wheel steering." Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185963.

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Sensitivity analysis methods are investigated for the optimal design of multibody systems. In order to overcome the shortcomings inherent in existing methods, a "mixed" method is developed. The beneficial features of the finite difference and the direct differentiation methods, and equations of motion in the joint coordinates are employed in this method. As a realistic application of the sensitivity analysis, a Four-Wheel-Steering vehicle with complete suspension systems and comprehensive analytical tire model is implemented. This model keeps full nonlinearity in the governing equations of motion for accuracy, and it is simulated using an existing general-purpose multibody dynamics simulation package. However, by using the transient dynamic analysis of the nonlinear model, optimal design parameters are dependent on driving scenarios. Therefore, the transient behavior of the system is represented by a series of steady state configurations. Hence, a steady state analysis procedure which finds a steady state configuration from an arbitrary initial condition is developed. By using the steady state analysis and the sensitivity analysis, the optimal steering ratios between the angles of the front and the rear wheels are obtained over various driving conditions. A steering control strategy is developed for the vehicle simulation to follow a prescribed path. Finally, the simulation results using the optimal steering ratio are compared against the results of the conventional two-wheel steering and the steering ratio based on the linear bicycle model.

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16

馮潤開 and Yun-hoi Fung. "Linguistic fuzzy-logic control of autonomous vehicles." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1998. http://hub.hku.hk/bib/B29812690.

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17

Spell, Sabine. "Japanese automobile lobbying in Brussels : the role of the Japanese motor car industry in EU policy networks." Thesis, University of Stirling, 2000. http://hdl.handle.net/1893/2390.

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This study examines the lobbying by the Japanese automobile industry in the European Union. It investigates how the Japanese automobile industry interacts with the decision-making authorities in Brussels in its attempts to influence the policy process of the European Union. In the post-war period the Japanese automobile industry has expanded into all major world markets and plays an important economic and political role in these. However, until the 1990s, the Japanese automobile industry enjoyed hardly any interaction with the policy making institutions of the European Union. This has changed dramatically in the last decade but, thus far, the process has not been subject to any empirical investigation. This study, which is largely based upon interviews with the major actors in the process of interaction between the governing institutions and the automobile industry in the EU, aims to correct this deficiency. This thesis employed the policy network concept as a framework to develop an understanding of this particular case of government-interest group interaction. The thesis investigated whether the Western concept of policy networks could successfully be applied to the Japanese automobile industry as a non-western actor in the unique system of governance of the EU. By doing so, the thesis has demonstrated that the policy network concept is not a purely Western construct, but can be applied with equal validity to the case of Japan. Therefore, this thesis has taken an importani. a step towards proving the universal applicability of the policy network concept.

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18

Li, Ke. "Automotive engine tuning using least-squares support vector machines and evolutionary optimization." Thesis, University of Macau, 2012. http://umaclib3.umac.mo/record=b2580667.

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19

Khoudeir, Riad. "L'amélioration de l'habitabilité automobile de demain : l'application des principes de la construction architecturale de la maison dans la conception de l'habitacle des concepts-cars." Thesis, Vandoeuvre-les-Nancy, INPL, 2007. http://www.theses.fr/2007INPL004N/document.

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Notre recherche s’inscrit dans le domaine du génie industriel. Elle porte sur l’amélioration de l’habitabilité de l’habitacle de l’automobile de demain. Cette étude met en évidence l’influence de la conception de l’habitat sur la conception de l’habitacle de l’automobile. L’objectif de ce travail est de proposer un outil destiné à aider le concepteur de l’automobile à introduire les principes de la construction architecturale de l’habitat dans la conception de l’habitacle de l’automobile pour améliorer son habitabilité. Dans notre démarche expérimentale nous avons adopté des principes de la méthode d’analyse des tendances conjointe comme les mappings et les planches de catégorisation. Cette démarche montre que les concepteurs de l’automobile ont orienté leur démarche vers l’intégration de plus en plus de principes de la construction architecturale de l’habitat dans la conception de l’habitacle des concept-cars. L’enquête que nous avons effectuée auprès des architectes et des designers nous a confirmé que l’habitat et l’automobile partagent les mêmes critères de l’habitabilité. Aussi, elle nous a affirmé l’impact positif des principes de la construction architecturale de l’habitat sur l’amélioration des critères de l’habitabilité dans l’espace de l’habitacle automobile. Notre recherche ouvre des perspectives pour analyser l’impact des autres secteurs d’influence comme l’aéronautique et l’électronique sur la conception de l’automobile. Aussi, elle montre l’importance de l’analyse de l’impact de la conception de l’automobile sur la conception de l’habitat du futur
The research field of this work is Industrial Engineering. This paper presents a study made to improve tomorrow’s automobile cabin habitability. It is focused on showing the influence on car-interior design by today’s home-interior design. The objective of this work is to propose a tool intended to help automobile designers to introduce home architectural construction principles into the car’s cabin design to improve its habitability. In our experimental phase we adopted principles of the method of analysis of the joint tendencies such as mappings and boards of categorization. This step showed that car designers have been increasingly using the home architectural construction principles on the car’s cabin conception design. Our research took into account the opinion of experts in both areas: architecture and design. In this way, we can be certain that the home and the automobile share the same criteria of habitability. We could also confirm that home architectural principles have a positive impact on the improvement of the habitability criteria in space design of the automobile’s cabin. This work opens a research line to analyze the influence of different areas in automobile design, such as aeronautics and electronics. This study can also show the inverse perspective of how car design can eventually have an impact on the future home design

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20

Calvel, Sonia. "Conception d'organes automobiles par optimisation topologique." Phd thesis, Université Paul Sabatier - Toulouse III, 2004. http://tel.archives-ouvertes.fr/tel-00007196.

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Dans l'industrie automobile, les réductions de masse permettent des économies de matières premières et des gains importants en performance. Cet allégement ne peut cependant pas se faire au détriment des exigences en matière de confort et de sécurité. Dans ce contexte, l'objectif de l'optimisation topologique est de déterminer, en amont des projets, les caractéristiques générales des pièces mécaniques. Les logiciels commerciaux actuels ne permettant pas l'intégration de toutes les contraintes déclinées sur les projets véhicules, notamment les contraintes vibro-accoustiques, nous proposons dans cette thèse une méthodologie et une solution logicielle associée, permettant la prise en compte d'un cahier des charges conforme à ceux utilisés chez Renault. Nous combinons pour cela la méthode d'optimisation topologique SIMP et l'algorithme d'optimisation numérique FSQP. Après avoir évalué notre méthode sur des cas de géométrie simple, nous montrons son potentiel sur le cas d'une face accessoires.

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21

Van, Vuuren Christiaan Michael. "Modelling of internal combustion engine intake and exhaust processes." Thesis, Stellenbosch : Stellenbosch University, 2001. http://hdl.handle.net/10019.1/52343.

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Thesis (MScEng)--University of Stellenbosch, 2001.
ENGLISH ABSTRACT: This thesis is concerned with unsteady, one-dimensional flow, which closely mimics those found in the manifolds of internal combustion engines. The physical equations describing problems of this nature are presented and some of the important concepts introduced. These equations and concepts were verified by comparison to published results. The Method of Characteristics (MaC) for unsteady one-dimensional flow with friction and heat transfer was used to analyse the gas flow through the inlet and exhaust systems of an engine. The theoretical derivation of unsteady gas dynamic boundary conditions is presented and the integration with the unsteady pipe flow explained. A simulation flow model was developed to analyse the flow by using the Mae. Thisflow model was then incorporated into an engine simulation program, ESA,to simulate internal combustion engines and to predict the performance of a specific engine. A cam-profile model and an in-cylinder thermodynamic model are used to complete the ESAsoftware. Experimental work was done on a modified Nissan Z24/NA20 engine to evaluate the simulation model. The manifolds of the Nissan Z24/NA20 were modified to isolate one of the cylinders for a proper single cylinder model. More experimental work was done on a Volkswagen 1.6£ 8-valve and a 1.6£ 20-valve engine to obtain performance data on two inlet manifolds developed using the ESAsoftware. Performance data and pressure traces in the inlet manifold of the Nissan Z24/NA20 were recorded for comparison with the ESA software. Good correspondence was found between tested and modelled data and the differences varied between ±5% on engine performance data and pressure wave frequency predictions, and ± 10% on pressure pulse amplitudes.
AFRIKAANSE OPSOMMING: Hierdie tesis handeloor bestendige, eendimensionele vloei, wat die gasvloei in spruitstukke van binnebrandenjins naboots. Die nodige vergelykings wat hierdie tipe probleme beskryf asook van die belangrikste konsepte, word bespreek. Hierdie vergelykings en konsepte is met behulp van gepubliseerde data geverifieer. Die Metode van Karakteristieke (MVK) vir bestendige, eendimensionle vloei met wrywing en warmte oordrag, is gebruik om die gasvloei deur inlaat en uitlaat sisteme van 'n enjin te analiseer. Die teoretiese afleiding van bestendige gasdinamiese randvoorwaardes asook hul integrasie met die bestendige pypvloei, word verduidelik. 'n Simulasie vloeimodel is ontwikkelom die vloei met behulp van die metode van karakteristieke te analiseer. Hierdie vloeimodel is deel van 'n omvattende enjinsimulasie program, ESA. Dit word gebruik om binnebrandenjins te simuleer en enjinwerkverrigting te voorspel. 'n Nokprofielmodel en 'n termodinamiese ontbrandingsmodel word gebruik om die enjinsimulasie program af te rond. Eksperimentele toetse op 'n gemodifiseerde Nissan Z24/NA20 enjin is gebruik om die simulasie model te evalueer. Die spruitstukke van die Nissan Z24/NA20 is aangepas om een van die silinders te isoleer om so 'n geskikte enkelsilindermodel te skep. Verdere eksperimentele toetse is gedoen op Volkswagen 1.6£8- klep en 1.6£ 20-klep enjins. Werkverrigtingsdata is verkry op twee nuwe inlaatspruitstukke wat met behulp van die ESAsagteware ontwerp is. Werkverrigtingsdata en drukverdelingsdata in die inlaatspruitstuk van die Nissan Z24/NA20is aangeteken om te vergelyk met die resultate van die ESAsagteware. Goeie ooreenstemming is verkry tussen toets- en gemoduleerde data. Die verskille varieer tussen ±5% op enjin werkverrigtingsdata en drukpulsfrekwensie voorspellings, en ± 10%op drukpuls-amplitudes.

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22

Vong, Chi Man. "Integrated machine learning techniques with application to adaptive decision support system for automotive engineering." Thesis, University of Macau, 2005. http://umaclib3.umac.mo/record=b1637079.

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23

Gstalter, Étienne. "Réduction d’ordre de modèle de crash automobile pour l’optimisation masse / prestations." Thesis, Compiègne, 2020. http://www.theses.fr/2020COMP2576.

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Cette thèse est une contribution à un thème de recherche sur les applications de la réduction de modèle à l’ingénierie RENAULT. Elle fait suite aux travaux du projet IRT SystemX ROM (Réduction de modèles et Optimisation Multidisciplinaire) et aux thèses CIFRE RENAULT [Vuong], [Charrier]. L’application industrielle principale du thème est la mise au point de la structure d’un véhicule sollicité en crash; des travaux sont également en cours sur la combustion, l’acoustique et l’aérodynamique. Les travaux de cette thèse sont à la fois un apport à la méthode générique ReCUR et son adaptation à l’optimisation de la caisse d’un véhicule pour le crash. RENAULT utilise largement l’optimisation pour la mise au point de la caisse en crash, avec un outil d’optimisation numérique basé sur la méthode des plans d’expériences. Cette méthode nécessite beaucoup de calculs crash car cette simulation est considérée comme une boite noire, en utilisant uniquement les entrées et sorties. La méthode ReCUR prend le contre-pied en exploitant un maximum d’informations de chaque simulation crash, dans le but de réduire fortement leur nombre. Les travaux de cette thèse ont permis de remplir cet objectif pour les applications de mise au point au nominal et pour l’optimisation robuste dans des cas complexes comme le choc frontal et arrière
This thesis is a part of a global research work dedicated to reduced-order modelling applications in the Renault engineering direction. It's research topic has been improved in the IRT System)('s project on Reduced Order Model and Multi-disciplinary Optimization. Some previous thesis can help understand the context. ([Vuong], [Charrier]). The main industrial application of the research theme is the focus on a body structure, in a crash loading. Some research works on acoustic, combustion and aerodynamic are currently ongoing. This thesis is both a contribution to the generic ReCUR method, and its application to a car body structure optimization for crash loadings. Engineering teams at Renault uses optimization to obtain the best crash simulation, with a numerical optimization software, based on designs of experiments. It requires a lot of crash simulation because each simulation is considered as unique, with only one response for each parameter. Only Inputs and Outputs are known. The ReCUR method consider that each simulation is a huge mine that needs our attention. We hope that we can decrease the number of crash simulation required to compute a model, by using much more data for each simulation

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Trakunsaranakom, Channarong. "Propositions pour une conception de produits manufacturiers collaborative, intuitive et tangible via des environnements de réalité virtuelle et augmentée." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAI022/document.

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Ce travail de recherche présente des concepts généraux pour l'évaluation de la performance des environnements de réalité virtuelle qui sont pertinents pour l'activité de conception des produits manufacturés. De plus il, vise à présenter aussi le contexte de la recherche pour l'industrie automobile thaïlandaise, car cette thèse soulaite elevelopper de nouvelles connaissances au profit de l'économie thaïlandaise. Cette recherche couve plusieurs contextes concernant l'interaction homme machine mais aussi l'évaluation de la réalité virtuel pour dans les secteurs industriels et éducatifs. L'état de l'art pertinent pour cette recherche comprend les thématiques: interface utilisateur, les problèmes liés aux facteurs humains, mais aussi l'évaluation de l'utilisabilité, le souhait ici est d'aller plus loin vers l'évaluation de l'utilité des système realité virtuelle. Nous devons identifier des critères abstraits d'évaluation dont, l'affordance, l'ergonomie, l'intuitivité, la tangibilité et la fatigue qu'implique ces environnement. Cette évaluation de l'environnement de réalité virtuelle nécessite le développement el' une method adapté à ces critères. Nous sommes spécifiquement intéressé par les étapes de conception ou de préparation de la fabrication, et plus particulièrement dus les activités d'assemblage et de simulation de mouvements. La conception d'un environnement de réalité virtuelle et la mise en œuvre d'une application informatique qui soutient l'évaluation de ces activités sont présentées. L'objectif principal d'une telle application reste l'évaluation de la performance des environnements de réalité virtuelle pour soutenir les tâches des concepteurs et des ingénieurs.Cette recherche a conduit à deux expériences: la première pour valider l'évaluation et la comparaison de la performance d'un environnement de realité virtuel par l'utilisation de capteurs de base mesmont la complétude de la tâche, sa durée et l'instabilité des gestes de l'utilisateur. La tâche testée connect ne l'assemblage de vis permettant l'analyse des mouvements de base tels que la translation, la rotation, l'orientation et l'insertion dans les alésages. Nous avons mis en œuvre l'expérience sur quatre environnements et avons invité 40 participants à notre protocole expérimental. La deuxième expérience a été organisée autour d'une simulation de mécanisme de came à barillet qui fonctionne avec un seul mouvement de rotation mais qui fournit une trajectoire 3D de complexe. Les experts en conception peuvent avoir des difficultés à anticiper le comportement de ce système. Ils éprouvent généralement des difficultés lors du réglage des paramètres de conception pour s'assurer que le mécanisme fonctionne bien. On étudie donc la capacité de la réalité virtuelle à surpasser ces difficultés. Si cette capacité est démontrée, il est également prévu d'évaluer et de comparer les performances du système d'environnement de la réalité virtuelle par l'utilisation d'une technique d'évaluation abstraite de haut niveau associée aux capteurs de bas niveau. Trente participants ont été impliqués dans cette expérience où les deux capteurs de base ont été capturés et des critères de haut niveau ont été évalués via un questionnaire. Encore une fois, les quatre environnements, y compris la stéréoscopie ou le dispositif haptique, ont été utilisés pour établir des comparaisons à l'égard de cette nouvelle tâche
The aim of this research introduces general concepts for performance assessment of virtual reality environments which are relevant to the design activity of manufactured products. Moreover, it aims to present also the context of the research respect to the Thai automotive industry, because this thesis expect to build new knowledge for the benefit of Thailand economy. This research covers several contexts of Human-Computer Interaction research as well as evolution of the VR assessment in the industrial and educational sector. The state of the art with direct relevance for the current research includes: user interface, human factor issues but also usability assessment but the wish here is to go a step further towards utility assessment. This research focuses on abstract level assessment criteria including: affordance, ergonomics, intuitiveness, tangibility, and tiredness assessments. We propose and analyse an assessment method of virtual reality for given activities. We are specifically concerned by activities involved at design stage or at manufacturing preparation stage and we have a deep focus on assembly activity and motion simulation. The design of a virtual reality environment and the implementation of a computer application that supports the evaluation of these activities are presented. The main objective of such application remains the assessment of the performance of virtual reality environments to support the tasks of designers and engineers.This research consists of two main activities: The first experience to validate the evaluation and comparison of the performance of the VRES by the use of low basic sensors consisting of docking quality, task duration, and gesture instability sensor. The experimental task is a set of simple screw assemblies allowing the analysis of the basic movements such as translation, rotation, orientation, and insertion into the holes. We have implemented the experiment on four environments and invited 40 participants to our experiment protocol. The second experience was thus organized around a barrel cam mechanism simulation which is operated with a single rotation motion but which provides a complex cam 3D trajectory. Even design experts may have some difficulties to anticipate the behaviour of this system. They usually experience difficulties when tuning design parameters to ensure that the mechanism is working well. It is thus investigated virtual reality capacity to overpass these difficulties. If this capacity is demonstrated, it is also expected to evaluate and compare the performance of the virtual reality environment system by the use of high level abstract assessment technique combined with low level sensors. Thirty participants have been involved in an experience where both basic sensors and high level assessment criteria were captured. Four virtual reality environments including either stereoscopy or haptic force-feedback device were compared respect to a given task

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Patry, Gaëtan. "Clés de progrés technico-économiques des batteries lithium-ion pour la traction automobile." Thesis, Paris, ENSAM, 2014. http://www.theses.fr/2014ENAM0065/document.

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Les véhicules électriques et hybrides présentent des avantages considérables qui les rendent attrayants, mais ont un coût élevé limitant leur succès. Ce travail a pour but de contribuer à la baisse du coût des batteries lithium-ion, inducteur majeur du prix des véhicules électriques, en proposant et en évaluant des pistes d'optimisation. Pour cela, une visibilité fiable et détaillée de la structure de coût de ces batteries est un prérequis. C'est pourquoi une méthodologie de modélisation des coûts des batteries lithium-ion en lien avec la conception technique, ainsi que des référentiels économiques sur le procédé de fabrication et les matières ont été mis au point. La modélisation présentant une part d'incertitude, une méthode innovante d'évaluation de celle-ci a aussi été développée. L'utilisation de ce modèle de coût a permis la détection et l'évaluation de piste de progrès. Ainsi, une piste de progrès notable soulevée dans cette thèse porte sur un paramètre de conception négligé dans la littérature : l'épaisseur d'enduction de l'électrode. Ce modèle a aussi permis de confirmer un point déjà remarqué dans plusieurs publications : le poids considérable des matériaux actifs dans le coût total. Pour comprendre les raisons de ce fait, un modèle de coût de ces composés a été développé et a permis de mettre en lumière des voies de réduction. In fine, ce travail propose pour la première fois une modélisation détaillée jusqu'aux précurseurs des matériaux actifs de la structure de coût des batteries lithium-ion et indique des leviers de réduction. Ceci constitue un résultat remarquable, offrant de nouvelles clés pour l'optimisation technico-économique des batteries lithium-ion pour la traction automobile
Electric and hybrid vehicles are particularly attractive. They offer several advantages, but at a high cost, which explains their current limited success. The purpose of this work is to contribute to the cost reduction of lithium-ion batteries, the main cost factor in electric vehicles. For the evaluation of cost reduction solutions, a clear and detailed comprehension of the structure of the battery cost is required. A complete environment for the cost modelling of cells for lithium ion batteries has also been developed: two cost models and two databases. This environment is made in order to precisely calculate the cost of a battery using the design parameters. Since there are uncertainties surrounding the cost modelling, an innovative method for the assessment of this uncertainty has also been developed. Using the cost model, several ways of improvement for lithium-ion batteries have been detected and quantified. Thus, a way to reduce the cost evaluated in this work is concerned with a design parameter neglected in the literature: the electrode coating thickness. This model has also confirmed a point already suggested on several papers: the preponderance of active materials on overall cost of lithium-ion batteries. To understand the reasons behind this fact, a cost model for active materials has been developed. New ways of cost reduction have been highlighted with this model. Finally, this work proposes for the first time a complete modelling of cells for lithium-ion batteries, detailed up to materials precursors. It also indicates several ways to reduce the cost of these batteries. This work gives to the community a comprehensive view on the cost structure, essential for the optimization of lithium-ion batteries

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Binois, Mickaël. "Uncertainty quantification on pareto fronts and high-dimensional strategies in bayesian optimization, with applications in multi-objective automotive design." Thesis, Saint-Etienne, EMSE, 2015. http://www.theses.fr/2015EMSE0805/document.

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Cette thèse traite de l’optimisation multiobjectif de fonctions coûteuses, aboutissant à laconstruction d’un front de Pareto représentant l’ensemble des compromis optimaux. En conception automobile, le budget d’évaluations est fortement limité par les temps de simulation numérique des phénomènes physiques considérés. Dans ce contexte, il est courant d’avoir recours à des « métamodèles » (ou modèles de modèles) des simulateurs numériques, en se basant notamment sur des processus gaussiens. Ils permettent d’ajouter séquentiellement des observations en conciliant recherche locale et exploration. En complément des critères d’optimisation existants tels que des versions multiobjectifs du critère d’amélioration espérée, nous proposons d’estimer la position de l’ensemble du front de Pareto avec une quantification de l’incertitude associée, à partir de simulations conditionnelles de processus gaussiens. Une deuxième contribution reprend ce problème à partir de copules. Pour pouvoir traiter le cas d’un grand nombre de variables d’entrées, nous nous basons sur l’algorithme REMBO. Par un tirage aléatoire directionnel, défini par une matrice, il permet de trouver un optimum rapidement lorsque seules quelques variables sont réellement influentes (mais inconnues). Plusieurs améliorations sont proposées, elles comprennent un noyau de covariance dédié, une sélection du domaine de petite dimension et des directions aléatoires mais aussi l’extension au casmultiobjectif. Enfin, un cas d’application industriel en crash a permis d’obtenir des gainssignificatifs en performance et en nombre de calculs requis, ainsi que de tester le package R GPareto développé dans le cadre de cette thèse
This dissertation deals with optimizing expensive or time-consuming black-box functionsto obtain the set of all optimal compromise solutions, i.e. the Pareto front. In automotivedesign, the evaluation budget is severely limited by numerical simulation times of the considered physical phenomena. In this context, it is common to resort to “metamodels” (models of models) of the numerical simulators, especially using Gaussian processes. They enable adding sequentially new observations while balancing local search and exploration. Complementing existing multi-objective Expected Improvement criteria, we propose to estimate the position of the whole Pareto front along with a quantification of the associated uncertainty, from conditional simulations of Gaussian processes. A second contribution addresses this problem from a different angle, using copulas to model the multi-variate cumulative distribution function. To cope with a possibly high number of variables, we adopt the REMBO algorithm. From a randomly selected direction, defined by a matrix, it allows a fast optimization when only a few number of variables are actually influential, but unknown. Several improvements are proposed, such as a dedicated covariance kernel, a selection procedure for the low dimensional domain and of the random directions, as well as an extension to the multi-objective setup. Finally, an industrial application in car crash-worthiness demonstrates significant benefits in terms of performance and number of simulations required. It has also been used to test the R package GPareto developed during this thesis

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Oliveira, Leonardo Presoto de. "Uma abordagem interativa para auxiliar no diagnóstico automotivo." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/3133.

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Fundação Araucária de Apoio ao Desenvolvimento Científico e Tecnológico do Paraná
Este trabalho tem como objetivo desenvolver uma abordagem para auxiliar as montadoras na obtenção de informações sobre os problemas e falhas que ocorrem nos veículos durante o seu uso pelos motoristas, relacionando os dados obtidos com a leitura da telemetria do veículo, assim como as percepções do motorista sobre uma determinada falha. A exploração de técnicas que auxiliam o diagnóstico automotivo é um problema a ser discutido na engenharia. As técnicas de diagnóstico devem fornecer suporte à grande gama de sistemas que surgirão nos próximos anos. Assim, é possível também utilizar a conectividade que os celulares e veículo dispõem na atualidade, com o intuito de evoluir o produto oferecido e melhorar a experiência do cliente enquanto dirige. A inclusão do cliente no processo de diagnóstico, visa permitir que os projetistas identifiquem pontos que podem ser melhorados no carro, mesmo que não apresentem erro aparente. A opinião do cliente pode ser considerada, uma vez que ele é incluído no processo como um novo “sensor" (o mais inteligente e importante de todos) capaz de reportar suas percepções. Considerando este fato, a motivação deste trabalho se encontra em: (i) Procurar alternativas para aplicar de maneira eficiente a conectividade dos veículos no processo de diagnóstico; (ii)Permitir que as montadoras possam obter informações mais concretas dos veículos que comercializam. O objeto é fornecer um sistema de interface entre o usuário e o carro auxiliando a realização dos diagnósticos preventivos mais completos do que apenas usando a telemetria. Neste projeto busca-se que haja uma interação maior com o motorista, e que a experiência das montadoras possa entrar no processo de diagnóstico. Mesmo que o cliente não tenha tanta intimidade com o funcionamento do veículo, o sistema deve orientar o motorista no processo. A entrada de dados do cliente é realizada por texto ou comando de voz. Para a análise desta entrada de dados do cliente foi realizado um estudo de mineração de dados em bases que a montadora já possuía. Estas bases são entrevistas telefônicas nas quais a montadora pergunta ao cliente problemas percebidos no carro, e então as respostas são transcritas para a base. O estudo de mineração de dados foi realizado para a criação do classificador que é responsável por receber os dados de entrada do cliente e classifica-lo em um determinado problema ligado à multimídia ou relacionado ao motor do veículo. O software contido no celular será responsável por solicitar ao sistema de sensores do veículo as leituras necessárias para que o cliente obtenha as informações que deseja. Foi realizado um experimento no qual analistas de diagnóstico responderam a um questionário que buscava analisar se o sistema proposto realmente influenciava no processo de diagnóstico, fazendo com que a solução dos problemas no veículo seja realizada em menos etapas, se comparado com o processo atual. Os resultados mostraram que a abordagem diminuiu o número de etapas necessárias para a obtenção do diagnóstico correto. Dos três estudos de caso realizados, as etapas necessárias para se chegar ao diagnóstico apropriado diminuiu em uma etapa para o primeiro estudo de caso, diminuiu uma etapa para o segundo estudo de caso, e três etapas a menos para o terceiro estudo de caso. Com estes resultados foi possível demonstrar que a abordagem proposta influiu no processo de diagnóstico aplicado atualmente pelas montadoras e concessionárias analisadas.
The goal of this project is to develop an approach to assist automakers in obtaining information about the problems and failures that occur in the vehicles during their use by drivers, relating the data obtained by reading the telemetry of the vehicle, as well as the perceptions of the driver about a particular failure. The exploration of techniques to optimize automotive diagnosis is a problem to be discussed in Engineering. Diagnostic techniques should support the wide range of systems that will emerge in the coming years. Thus, it is also possible to use the connectivity that mobile phones and vehicles have today, in order to evolve the product offered and improve the customer experience while driving. The customer inclusion in the diagnostic process aims to allow engineers identifies points to be improved in the car, even if they dont present an apparent error. The customer opinion should be considered, since he/she is included in the process as a new "sensor"(the most intelligent and important of all) able to report his/her perceptions. Considering this fact, the motivation of this research is: (i) search for alternatives to efficiently apply vehicle connectivity in the diagnostic process, (ii) enable automakers to obtain more concrete information on the vehicles they sell. The object is provide an interface between the user and the car helping them to perform a more complete preventive diagnoses than only using telemetry. In this project it is sought that there is a greater interaction with the driver, and the experience of the automakers could be included the diagnostic process. Even if the customer isnt so accustomed with the operation of the vehicle, the system must guide the driver by the process. The customer input data is performed by text or voice command. The analysis of this customer input data, a data mining study was performed based on a base that automaker already had. These bases are telephone interviews in which the automaker asks the customer for perceived problems in the car, and then the answers are transcribed to the base. The data mining study was performed to create one classifier which was responsible for receiving the input data from the customer and sorting it into a particular problem related with the multimídia or related to the motor of the vehicle. The software contained in the mobile phone will be responsible asking to the vehicle sensor system for the readings necessary for the customer can to obtain the information he/she wants. An experiment was carried out in which diagnostic analysts answered a questionnaire that sought to analyze whether the proposed system actually influenced the diagnostic process, so the solution of the problems in the vehicle was performed on less steps compared to the current process. The results showed the approach reduced the number of steps required to obtain the correct diagnosis. Of the three case studies performed, the steps required to arrive at appropriate diagnosis decreased in one step to the first case study, one step to the second case study decreased, and three less steps to the third case study . With these results it was possible to demonstrate that the proposed approach influenced the diagnostic process currently applied by the automakers and concessionaires analyzed.

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Mignerey, Renaud. "Designer les interactions humain-monde pour susciter des émotions positives : application à l’automobile." Thesis, Compiègne, 2019. http://www.theses.fr/2019COMP2503/document.

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Dans un contexte de fortes pressions concurrentielles et réglementaires, les constructeurs automobiles introduisent sur le marché des véhicules dont les caractéristiques sont proches. Si les émotions suscitées par l’expérience de conduite constituent un puissant levier de différenciation, les concepteurs de voitures rattachent principalement la dimension affective aux propriétés stylistiques de leurs véhicules. Avec des innovations qui ne sont envisagées que dans une perspective fonctionnelle, les constructeurs proposent ainsi à leurs clients des prestations similaires, sans tenir compte des facteurs relationnels sous-jacents à l’utilisation d’un véhicule. Pourtant, la littérature met en avant l’importance de la dimension émotionnelle des relations sociales, qui représente selon nous une opportunité pour le Groupe Renault de se différencier, en proposant une nouvelle expérience de conduite orientée sur les interactions inter-conducteurs. Nous avons commencé notre travail par un premier terrain d’observation, dont l’objectif a été de déterminer les conditions et les leviers permettant l’établissement d’une relation entre les usagers de la route. Sur la base des premiers résultats valorisant la perception mutuelle de deux conducteurs, nous avons réalisé une expérimentation dite minimaliste comparant deux modalités de perception, appelées information perceptive et activité perceptive, dans le cadre d’une action collaborative. Cette étude souligne le rôle crucial de la dynamique interpersonnelle sur les mécanismes de la compréhension sociale : les résultats montrent l’intérêt, d’un point de vue émotionnel, d’accéder à ce à quoi l’autre est attentif. Nous nous sommes ensuite inspirés de ces résultats pour designer un dispositif de perception et d’interaction et étudier son rôle dans l’apparition d’émotions positives lors de la conduite sur route. Par le biais d’une expérimentation sur simulateur, nous avons pu faire émerger un nouveau type d’expérience de conduite résultant de la manipulation de ce dispositif. Cette thèse, sur la base d’un principe théorique mis à l’épreuve dans une expérimentation de terrain impliquant les usagers de la route, suit un processus itératif propre à une démarche de recherche-projet. Elle s’appuie sur une réalisation conceptuelle qui n’est pas une finalité mais un préalable. Elle propose des pistes de conceptions pour le design d’une nouvelle fonctionnalité intégrée dans le véhicule, tirant parti du contexte social de la conduite pour susciter des émotions positives entre conducteurs
In a context of strong competition and regulatory pressures, the vehicles on the market share common characteristics. Even though emotions elicited by the driving experience are a powerful lever for differentiation, manufacturers mainly attach the affective dimension to the stylistic properties of their vehicles. They only consider innovations in a functional perspective and offer their customers similar services without regarding the relational factor underlying the use of a vehicle. However, the literature highlights the importance of the emotional dimension of social relations, which in our opinion represents an opportunity for the Renault Group to differentiate itself by proposing a new driving experience based on interactions between drivers. We began our work with an observation field. Our purpose was to determine the conditions and levers establishing a relationship between road users. On the basis of the first results valuing the mutual perception of two drivers, we carried out a minimalist experiment comparing two modes of perception, namely the perceptive information and theperceptual activity, within the framework of a collaborative action. This study emphasizes the crucial role of interpersonal dynamics on the mechanisms of social understanding: the results show the interest, from an emotional point of view, of accessing to what the other is attentive to. We then used these results to design a device for perception and interaction purposes and we studied its role in the emergence of positive emotions when driving. Through a simulator experiment, we have been able to bring out a new type of driving experience resulting from the manipulation of this device. This thesis is based on a theoretical principle put to the test in a field experiment involving road users. We follow an iterative process specific to a research-project approach. We propose a conceptual realization that is not a purpose but a prerequisite. Based on the fact that driving is in itself a social interaction, we suggest ideas for the design of a new feature integrated into the vehicle which arouses positive emotions between drivers

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Moustapha, Maliki. "Métamodèles adaptatifs pour l'optimisation fiable multi-prestations de la masse de véhicules." Thesis, Clermont-Ferrand 2, 2016. http://www.theses.fr/2016CLF22670/document.

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Cette thèse s’inscrit dans le cadre des travaux menés par PSA Peugeot Citroën pour l’allègement de ses véhicules. Les optimisations masse multi-prestations réalisées sur le périmètre de la structure contribuent directement à cette démarche en recherchant une allocation d’épaisseurs de tôles à masse minimale qui respectent des spécifications physiques relatives à différentes prestations (choc, vibro-acoustique, etc.). Ces spécifications sont généralement évaluées à travers des modèles numériques à très haute-fidélité qui présentent des temps de restitution particulièrement élevés. Le recours à des fonctions de substitution, connues sous le nom de métamodèles, reste alors la seule alternative pour mener une étude d’optimisation tout en respectant les délais projet. Cependant la prestation qui nous intéresse, à savoir le choc frontal, présente quelques particularités (grande dimensionnalité, fortes non-linéarités, dispersions physique et numérique) qui rendent sa métamodélisation difficile.L’objectif de la thèse est alors de proposer une approche d’optimisation basée sur des métamodèles adaptatifs afin de dégager de nouveaux gains de masse. Cela passe par la prise en compte du choc frontal dont le caractère chaotique est exacerbé par la présence d’incertitudes. Nous proposons ainsi une méthode d’optimisation fiabiliste avec l’introduction de quantiles comme mesure de conservatisme. L’approche est basée sur des modèles de krigeage avec enrichissement adaptatif afin de réduire au mieux le nombre d’appels aux modèles éléments finis. Une application sur un véhicule complet permet de valider la méthode
One of the most challenging tasks in modern engineering is that of keeping the cost of manufactured goods small. With the advent of computational design, prototyping for instance, a major source of expenses, is reduced to its bare essentials. In fact, through the use of high-fidelity models, engineers can predict the behaviors of the systems they design quite faithfully. To be fully realistic, such models must embed uncertainties that may affect the physical properties or operating conditions of the system. This PhD thesis deals with the constrained optimization of structures under uncertainties in the context of automotive design. The constraints are assessed through expensive finite element models. For practical purposes, such models are conveniently substituted by so-called surrogate models which stand as cheap and easy-to-evaluate proxies. In this PhD thesis, Gaussian process modeling and support vector machines are considered. Upon reviewing state-of-the-art techniques for optimization under uncertainties, we propose a novel formulation for reliability-based design optimization which relies on quantiles. The formal equivalence of this formulation with the traditional ones is proved. This approach is then coupled to surrogate modeling. Kriging is considered thanks to its built-in error estimate which makes it convenient to adaptive sampling strategies. Such an approach allows us to reduce the computational budget by running the true model only in regions that are of interest to optimization. We therefore propose a two-stage enrichment scheme. The first stage is aimed at globally reducing the Kriging epistemic uncertainty in the vicinity of the limit-state surface. The second one is performed within iterations of optimization so as to locally improve the quantile accuracy. The efficiency of this approach is demonstrated through comparison with benchmark results. An industrial application featuring a car under frontal impact is considered. The crash behavior of a car is indeed particularly affected by uncertainties. The proposed approach therefore allows us to find a reliable solution within a reduced number of calls to the true finite element model. For the extreme case where uncertainties trigger various crash scenarios of the car, it is proposed to rely on support vector machines for classification so as to predict the possible scenarios before metamodeling each of them separately

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Sikora, Celso Gustavo Stall. "Scheduling projects in operating systems: an application on assembly line balancing." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2859.

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Анотація:

Fundação Araucária; RENAULT; Seti
A Pesquisa Operacional investiga as (melhores) formas de se configurar e coordenar sistemas ou operações usando técnicas de otimização. Geralmente, a otimização de um sistema é modelado com base no estado final almejado. Porém, como atingir ou implementar tal estado final em sistemas é pouco retratado na literatura. Esta dissertaçãode mestrado propõe uma nova classe de problema de otimização: a programação das operações entre o estado inicial e o final de um sistema, o Problema de Implementação. A programação das operações é especialmente importante para linhas de montagem. A indústria automobilística é fortemente baseada em linhas de produção que podem ser usadas até 24 horas por dia. Assim, as oportunidades de intervenções para mudar ou otimizar o sistema produtivo são poucas. As condições de implementação aplicadas ao balanceamento de linhas produtivas são discutidas, e as características observadas resultam no proposto Problema de Implementação de Linhas de Montagem (PILM). Na dissertação, um guia de modelagem baseado em Programação Linear Inteira Mista (PLIM) é desenvolvido para a formulação de diversas variações do Problema de Implementação. As instruções de modelagem são usadas para desenvolver um conjunto de modelos PLIM para o Problema de Implementação de Linhas de Montagem. Para a obtenção de resultados, um conjunto de instâncias é proposto. Assim, uma análise de sensibilidade em função de cada um dos parâmetros formadores das instâncias é realizada. As formulações são comparadas, junto com as diferentes formas de apresentar e resolver o problema. Ademais, um método de decomposição é usado para resolver um problema industrial real. A modelagem mostrase correta para a divisão da implementação de mudanças em linhas de montagem. Os resultados mostram que a divisão do esforço de implementação resulta em apenas poucas mudanças a mais (cerca de 7% para os casos pequenos e médios) comparadas com a implementação em uma fase. A possibilidade de programar a implementação em etapas menores aumenta a aplicabilidade de projetos, que, de outra forma, requeririam grande paradas de produção.
Operations Research investigates the (best) ways to configure and coordinate systems or operations with optimization procedures. Usually, the optimization of a system is modeled based on the aimed final configuration. However, little is published about how to reach or implement such optimal configurations in the systems. This master thesis proposes a new class of optimization problem: a scheduling of operations between initial and final states of a system, the Implementation Problem. The scheduling of operations is especially important to assembly lines. The automotive industry strongly relies on production lines that can operate 24 hours a day. Thus, the intervention opportunities to change or optimize the production system are very few. The implementation conditions of balancing on assembly lines are discussed, and the observed characteristics result in the proposal of the Assembly Line Implementation Problem (ALIP). The master thesis proposes a Mixed-Integer Linear Programming (MILP) modeling guide for the formulation of several variations of Implementation Problems. The modeling instructions are used to develop a set of MILP models for the Assembly Line Implementation Problem. For the results, a dataset is proposed and a sensitivity analysis on each of the consistent parameters of the dataset is performed. The proposed formulations are compared, along with the different forms of presenting and solving the problem. Furthermore, a decomposition method is used to solve a real-world industrial problem. The modeling correctly represents the division of the implementation of changes in assembly lines. The results show that the division of the effort in multiple stages only need a few more changes (around 7\% for the small and medium cases) comparing to a straightforward implementation. The possibility of scheduling the implementation in smaller steps increases the applicability of projects that otherwise would require a large system's stoppage time.

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31

Taheri, Ali. "Définition des indicateurs de l'efficience inventive pour caractériser les activités inventives en R&D : application au domaine de l’automobile." Thesis, Strasbourg, 2015. http://www.theses.fr/2015STRAD025/document.

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[...] Le sujet de cette thèse intervient dans le cadre du projet DEFI et vise à caractériser la notion d'Efficience Inventive en Conception afin d'élaborer des moyens de mesure de cette dernière. L’objectif étant à terme d’aboutir à l'adoption d’indicateurs aidant les entreprises à situer leurs capacités inventives en R&D. Par la suite, les entreprises ayant adopté ces indicateurs pourront, le cas échéant, entamer des actions d'évolution de leurs pratiques afin que la valeur de ces indicateurs évolue dans le sens recherché. Aux vues de la diversité des typologies d’entreprises et l’ampleur d’un tel sujet, notre recherche est focalisée sur les projets de conception de produits au sein des départements R&D de l’industrie automobile. Afin de mener cette recherche et définir les indicateurs de l’efficience inventive, nous avons étudié dans un premier temps les critères inhérents à la conception inventive. Selon nos travaux, la mesure de la performance inventive est corrélée à l’efficience inventive et doit considérer son efficacité par des caractéristiques ciblées, l’étude des connaissances impliquées et des ressources consommées. Notre mesure de l’efficience inventive est aussi basée sur l’analyse des flux des connaissances en jeu tout au long du processus d’innovation technologique, et particulièrement dans la phase de pré-développement. Elle analyse la relation entre ce qui est reçu et ce qui est appliqué ou consommé par rapport à l’inventivité. La mesure de l’inventivité est alors basée sur l’évaluation de l’idéalité, la nouveauté et l’utilité de ce qui sort du processus de conception de produit. L’ensemble des méthodes d’évaluation développées dans ce travail pour chaque critère d’inventivité, et l’efficience inventive, sont intégrés dans un système d’évaluation concret nommé IDPMS (Inventive Design Performance Measurement System) destiné à aider les directeurs des projets de la conception de produit et R&D à observer la performance inventive des équipes projet, et tenter d’améliorer les activités inventives. Donc, ce travail se catégorise dans le domain des sciences de l’ingénieur. Depuis plus de deux décennies, notre laboratoire (le LGéCo) travaille à la construction, d’abord théorique, puis déclinée en méthodes et outils, de nouvelles approches destinées à accompagner les mutations industrielles de l’ère de la qualité vers l’ère de l’innovation. A cet égard, cette thèse fournira un chaînon manquant : celui qui concerne l’évaluation, et la mesure de ce qui caractérise l’amont de l'innovation afin d’aider les entreprises à entrer, par rapport à ces dernières, en logique de performance
[...] This thesis was defined in the DEFI project to characterize the notion of efficiency in Inventive Design, and develop the metrics of inventive-design. The objective of this proposal is to define inventive performance indicators to enhance the creative capacity in the automotive industry. The research is focused on the NPD projects of R&D department, which are known as the responsible of technological evolutions. In this respect, the main elements of design performance, and the main criteria of inventiveness are studied and merged together. The inventive performance of a R&D team is concerned with the efficiency of their activities to create inventive designs when they apply existing knowledge, and/or use creative resources. This analyzes the relationship between what is received and what is applied or consumed to achieve higher inventiveness degree. The measures of inventiveness are based on the evaluation of novelty, resourcefulness, and usefulness of what comes out from design activities. All the evaluation methods developed in this work are integrated into a concrete system as IDPMS (Inventive Design Performance Measurement System), and an initial version of the IDPMS application is developed, by which R&D and project managers can observe the inventive performance of their NPD projects. So this work is categorized in Engineering Science for specifying performance indicators of inventive design activities. In recent years, our laboratory (LGeCo) focused on developing theoretical methods, then appropriate tools to accompany the industrial changes from the era of quality to the era of innovation. In this regard, this thesis provides the missing link of this effort by evaluating the main characteristics of inventions in engineering level to help companies enter into a logic performance along their innovation projects

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Lopes, Thiago Cantos. "Balancing optimization of robotic welding lines: model and case study." Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2621.

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Анотація:

FA; UTFPR; RENAULT
Linhas robóticas de solda são comuns na indústria automobilística. Durante a produção de um veículo, sua estrutura metálica precisa ser soldada em um único corpo resistente. Isso é feito por meio de centenas de soldas a ponto por resistência, cada uma liga localmente duas ou mais placas metálicas. Distribuir eficientemente esses pontos entre robôs é particularmente desafiador, levando em conta que: cada robôs podem fazer acessar uma parte dos pontos de solda, há tempo de movimentação entre pontos e robôs podem colidir entre si se ocuparem o mesmo espaço físico ao mesmo tempo. Há muitas maneiras factíveis de distribuir pontos de solda. No entanto, cada uma gera um resultado econômico diferente: Se um robô soldar muitos pontos se tornará um gargalo e reduzirá a taxa média de produção.Obter o conjunto de decisões operacionais que gera o melhor desempenho é o objetivo de técnicas de otimização. Há uma ampla variedade de técnicas descritas na literatura de pesquisa operacional e ciência da computação: modelos matemáticos, algoritmos, heurísticas, meta-heurísticas, etc. No contexto industrial, tais técnicas foram adaptadas para diversas variantes de problemas práticos. No entanto, estas adaptações só podem resolver as variantes para as quais foram idealizadas. Se por um lado podem se traçar paralelos entre vários aspectos de linhas robóticas de solda e tais variantes, por outro o conjunto completo de características das linhas estudadas não é tratável por (ou convertível em) nenhuma delas. A presente dissertação desenvolve uma abordagem para otimizar tais linhas, baseada em um modelo de programação linear inteira mista desenvolvido para descrever o problema. Ela também apresenta um estudo de caso para discutir e ilustrar possíveis dificuldades de aplicação e como superá-las. O modelo apresentado foi aplicado a dados de uma linha robótica de solda da fábrica, composta por quarenta e dois robôs, quatro modelos de veículos e mais de setecentos pontos de solda por veículo. A média ponderada da redução em tempo de ciclo obtida pelo modelo foi de 17.5%. Variantes do modelo, concebidas para auxiliar trabalhos futuros, são apresentadas e discutidas.
Robotic welding manufacturing lines are production lines common in automobile industries. During a vehicle's production, the vehicle's metal structure must be welded in a single resistant body. This is made by hundreds of spot-welding points, each of which tie locally two or more metal plates. Efficiently distributing these welding points amongst robots is particularly challenging, taking in account that: not all robots can perform all weld points, robots must move their welding tools between weld points, and robots might interfere with one another if they use the same geometrical space. There are multiple feasible manners to distribute the welding points. However, each of these forms generates different economical results: If a robot performs too many points, it will become a line bottleneck and reduce average throughput. To find the set of operational decisions that yields the best output is the goal of optimization techniques. There are a wide variety of such techniques described in operations research and computer sciences literature: mathematical models, algorithms, heuristics, meta-heuristics, etc. In the industrial context, these techniques were adapted to related line balancing problems. However, these adaptations can only solve the specific variants they were designed to address. While parallels can be drawn between aspects of robotic welding lines and many of such variants, the full combined set of characteristics of the studied lines is not treatable by (or convertible to) any of them. This dissertation develops a framework to optimize such lines, based on mixed-integer linear programing model developed to describe the problem. It also presents a case study to discuss and illustrate possible difficulties and how to overcome them. The presented model was applied to data from the factory's robotic welding lines composed of forty-two robots (divided in thirteen stations), four vehicle models and over seven hundred welding points for each vehicle. The weighted average reduction percentage in cycle time obtained by the model was 17.5%. Model variants, designed to aid further works are presented and discussed.

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Kaltcheva, Rossitza. "De l’isolement professionnel à la restauration de la fonction psychologique du collectif : la santé au travail, entre soliloque et pensée dialogique : le cas de l’intervention à l’ingénierie Renault." Thesis, Paris, CNAM, 2019. http://www.theses.fr/2019CNAM1279.

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Cette thèse trouve sa genèse dans une intervention en psychologie du travail, réalisée au sein de l’entreprise Renault, sous les modalités de la clinique de l’activité. L’intervention s’est articulée autour de deux volets : montage en usine et conception industrielle. La thèse porte sur le second terrain, conduit au Technocentre Renault. Le dispositif dialogique déployé a permis de faire reculer l’isolement professionnel en développant la fonction psychologique du collectif. La thèse soutient la possibilité de rendre compte de ce développement. Les analyses caractérisent des situations d’isolement réalisant des discours désertés par autrui ainsi que des dialogues, habités par autrui, signe d’un développement de la fonction psychologique du collectif. Les analyses interrogent les conditions d’installation d’un dispositif dialogique pérenne à l’ingénierie Renault. La conclusion met en exergue la fonction vitale du dialogue professionnel pour l’efficacité et la santé au travail
This doctoral thesis originated in an activity clinic intervention in work psychology conducted at the Renault company in France. The intervention covered two activities: assembly line activities and industrial design. The thesis concerns the second activity conducted at the Renault Technocentre. The dialogical process deployed made it possible to reduce isolation at work by developing the psychological function of the group. The assumption put forward is that it is possible to demonstrate this development. The analyses characterise the situations of isolation producing utterances devoid of the existence of others as well as dialogues inhabited by others, a sign of the development of the psychological function of the group. The analyses raise questions concerning the establishment of a lasting dialogical process in the Renault engineering department. Theconclusion highlights the vital role of professional dialogue for efficiency and health at work

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Lallou, Imane. "Coordination des acteurs d'un processus de conception complexe et incertain : vers un pilotage de la création de valeur intégrant des arbitrages risques/opportunités." Thesis, Paris Sciences et Lettres (ComUE), 2016. http://www.theses.fr/2016PSLED061/document.

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La conception automobile est un processus complexe, soumis à de fortes incertitudes et mettant en jeu une création de valeur multidimensionnelle. De plus, la coordination dans ce processus, impliquant une multitude d’acteurs de domaines variés et travaillant sur un produit lui-même complexe et incertain, s’avère difficile.Une analyse des méthodes de pilotage existantes dans la littérature nous a permis d’identifier des limites ne permettant pas de répondre simultanément à l’ensemble des caractéristiques de ce processus. Nous avons donc proposé une méthode de pilotage novatrice articulant Valeur Risques Opportunités. Celle-ci s’inscrit dans le cadre des travaux théoriques intégrant les deux champs de contrôle : le Management de la Performance (MP) et le Management des Risques (MR). Notre méthode de pilotage permettrait de dépasser les limites des méthodes existantes à travers l’adoption d’une approche holistique (prise en compte de l’ensemble des dimensions de valeur), systémique (prise en compte des interactions complexes entre les différents constituants du processus) et dynamique (intégration systématique des risques et des opportunités au pilotage de la création valeur).Pour mettre en œuvre notre méthode de pilotage dans le processus de conception du Groupe PSA, nous avons construit un prototype générique permettant la mobilisation des acteurs sur une trajectoire d’amélioration et la co-construction d’une manière dynamique d’une version applicable chez PSA. Nous nous sommes appuyée, dans notre démarche d’ingénierie de mise en œuvre, sur les travaux d’appropriation des outils de gestion et d’implémentation des innovations managériales complexes. Les résultats de la mise en œuvre nous ont permis : i) d’un côté, de confirmer l’intérêt de notre méthode de pilotage articulant Valeur Risques Opportunités ayant suscité l’intérêt de plusieurs acteurs clés, attesté par des améliorations effectives du pilotage des projets véhicule et de la coordination des acteurs et ; ii) d’un autre côté, de révéler des difficultés liées au décalage entre certaines de nos propositions, cherchant à construire des outils représentatifs de la complexité des mécanismes en jeu dans le processus de conception, et la volonté des acteurs de simplifier davantage la méthode et de se focaliser, dans un contexte de crise, sur la dimension économique et sur la gestion des risques. Dans notre thèse, nous proposons également quelques perspectives d’évolution de la fonction Contrôle de gestion, à travers l’intégration de notre méthode de pilotage, pour une meilleure adéquation avec les particularités du processus de conception automobile
Automotive design is a complex and uncertain process creating a multidimensional value. This process is also characterized by a difficult coordination of the multitude of actors from different areas involved in the design a complex and uncertain product.An analysis of existing control methods in the literature allows us to identify some limits which hamper the simultaneously response to all the characteristics of this process. We propose an innovative control method articulating Value, Opportunities and Risks. Our method contributes to the theoretical works proposing the integration of two major control fields: Performance Management (PM) and Risk Management (RM). Our method allows overcoming the limitations of existing control methods through the adoption of a holistic (taking into account all the dimensions of value), a systemic (taking into account the complex interactions between the various components of this process) and a dynamic approach (by a systematic integration of risks and opportunities to the control of value creation process).To implement this control method in PSA group design process we built a generic prototype. This allowed the mobilization of actors by fixing an improvement trajectory and a dynamic co-conception of an applicable version for PSA.The results of the implementation allowed us to : i) confirm the benefits of our control method articulating Value, Opportunities and Risks which interested several key actors and lead to some effective improvements in vehicle projects management and actors coordination and; ii) reveal difficulties dues to the gap between some of our proposals, seeking to build tools reflecting the design process complexity, and willingness of stakeholders to simplify the method and to focus, in a context of crisis, on the economic dimension and risk management.In our thesis, we also propose some perspectives to improve Management Control function, through the integration of our control method, for a better match with the characteristics of the automotive design process

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35

Lu, Ji. "A sensitivity analysis for the design parameters of a car side-view mirror." Thesis, 2005. http://hdl.handle.net/2440/69451.

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Анотація:

The objective of this project was to model a Ford Falcon side-view mirror and to establish a high degree of confidence in its accuracy, via experimental validation, so that the model could be used as a tool to predict the effect of design parameter changes.
Thesis (M.Eng.Sc.) -- University of Adelaide, School of Mechanical Engineering, 2005

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Cuderman, Jerry Ferdinand 1966. "Performance of passenger vehicle anti-lock braking system : an experimental study." 2001. http://hdl.handle.net/2152/10328.

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Mwangi, Maina Festus. "Development of granular-medium-based energy management system for automotive bumper applications." Thesis, 2009. http://hdl.handle.net/10321/589.

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Thesis submitted in compliance with the requirements of the Master's Degree in Technology: Mechanical Engineering, Durban University of Technology, 2009.
Automotive bumpers are installed primarily to minimize damage and harm to both the automobile and passengers during minor and low speed collisions. The efficacy of the current bumper systems lies in absorbing the impact energy. The primary mechanism for energy absorption is damage. In this study an attempt is made to shift from this traditional design platform by exploring non-destructive energy dissipation mechanisms. In pursuit of this, an alternative bumper system that simulates human-arm ergonomic response to impact has been proposed. The system capitalizes on the characteristic dissipative mechanics of granular media. A mathematical model describing the dissipative mechanics of the system is presented. The model shows that granular media can be used effectively to re-direct the impulse wave away from its axis of incidence. The resulting effect is that the impulse wave is attenuated through the thickness. A second mathematical model, based on the Concept of Energy Balance has been developed. Here, the total impact energy is shown to be absorbed or dissipated by the individual components of the system. The largest component of this energy is taken up by sliding and rotation of the granular media. Both models are validated by experimentation. A prototype system has been built and tested. The system effectively manages impact energy with minimal or no damage to the constituent components. The system demonstrates an ability to recover dimensionally when loaded under FMVSS conditions.

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Ravi, D. K. "Design studies relating to the brushless doubly-fed automotive alternator." Thesis, 1992. http://hdl.handle.net/1957/36225.

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The alternators in today's automobiles are of the claw-pole or Lundell construction, which is a readily manufactured, low-cost derivative of the conventional rotating dc field synchronous generator. The efficiency of the Lundell system is low due to a complicated magnetic circuit of predominantly solid steel and a high windage rotor structure. As the number of electrical devices in a car increases, so does the demand on the generator system. The Lundell alternator is not able to meet the demands and numerous alternative systems are under investigation. This led to the development of the brushless doubly-fed alternator system with the advantages of regulation over a wide speed range, competitive system cost based on inexpensive machine construction, low rating controller, diode rectifier and robust, low maintenance configuration. The conventional alternator has only one degree of control (de excitation), whereas the doubly-fed alternator has three control quantities: excitation magnitude, frequency and phase sequence. Excitation magnitude is used to regulate the output voltage, which leaves two control parameters to optimize efficiency over the alternator speed range. Simulation tools were developed for conducting design studies on the BDFM alternator system. Various stator and rotor configurations were studied through simulation and a few prototypes were built. A proof-of-concept prototype built in an existing induction machine frame achieved comparable efficiency characteristics to the Lundell System and exceeded the Lundell performance over part of the speed range. Significant performance improvements are expected for a new, optimized prototype which will not rely on the induction machine laminations, but will utilize custom components designed for this low voltage, high frequency application. Since the increase in automotive power demand is likely to be coupled with an increase in system voltage, a 24V, 2kW alternator system is investigated and simulation results are presented.
Graduation date: 1993

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Furrutter, Marco Klaus. "A control strategy for the power system of a hybrid vehicle." Thesis, 2012. http://hdl.handle.net/10210/7895.

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Анотація:

M.Ing.
The increase in awareness of the environmental problems resulting from emissions released from vehicles have forced governments and car manufactures to invest more time in to the designing a vehicle that is an alternative to petrol driven vehicles. This dissertation aims to introduce a control strategy to manage the flow of energy of different power sources that may be found on a vehicle. Hybrid vehicles are a possible solution to reducing carbon emissions that play a part in global warming. In this dissertation, di erent hybrid vehicles are de ned and their components discussed in detail. The possibility of more than one energy source to power the vehicle introduces more exibility in terms of the drivetrain but this increases the complexity of the energy control management. The goal is to optimize the energy control management to reduce fuel consumption and therefore reduce emissions. Operating procedures for the various hybrid con gurations are discussed. Simulations of the Energy Management System of the hybrid electric vehicle are used to develop the control optimization algorithm. Various control optimization procedures are discussed. Satisfactory results from the simulations allow the implementation of the hybrid onto a platform entered into the South African Solar Challenge 2010, which covered a distance of 4000 km. The Energy Management system selected for the parallel hybrid electric vehicle demonstrated fuel savings, which meant a reduction in emissions, which is the goal of any hybrid vehicle. Further investigations include more intelligent controllers to adjust the parameters of the energy management controller to allow for adaptation to various driving conditions, e.g. urban and motorway driving.

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"Effect of Continuously Variable Unit on Powertrain Dynamics." University of Technology, Sydney. Faculty of Engineering, 2004. http://hdl.handle.net/2100/340.

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This thesis studies the dynamic model and simulation of a Half-Toroidal (HT) type Continuously Variable Unit (CVU) integrated into a conventional powertrain. A simplified parametric model of a HT-CVU is constructed using Finite Element Method (FEM) in which the continuous variable speed unit is discretized into lumped masses, spring and damper elements. Linearized Finite Elements (FE) have been used to model the contacts between the toroids and rollers. The phenomenon of slip and spin associated with the rolling-slipping contacts of the traction drives are modelled kinematically. All Finite Elements including the CVU model are integrated into the complete powertrain system. Free Vibration Analysis (FVA) of the multi degree of freedom system is carried out for torsional vibration for High Gear (HGR) and Low Gear Ratio (LGR) conditions. Further, FVA is carried out with a lock-up clutch engaged at high speed range. The results of the FVA indicates significant changes in natural frequencies and corresponding mode shapes for both HGR and LGR condition with a change in HT-CVU gear ratios. Change in natural frequencies and mode shapes for both HGR and LGR conditions are also observed for varying contact torsional stiffness. The change is significant till a certain value of contact torsional stiffness. Further increase in contact torsional stiffness within the HT-CVU does not affect the natural frequencies and corresponding mode shapes significantly. The results of the modal analysis carried out for a HT-CVU integrated powertrain with a lock-up clutch engaged at high speed range illustrates the ability of the lock-up clutch to simultaneously suspend engine and roller element excitation. However, for certain natural frequencies the modal analysis of the integrated powertrain system indicates suspension of engine and input toroid but increased excitation for the roller element of the HT-CVU. The transient dynamic analysis is carried out to understand the behaviour of the CVU integrated into the complete powertrain and to identify and possibly correct potential problems associated with the system. The simulation is carried out for constant and variable throttle conditions for the powertrain with and without a lock up clutch engaged at high speed ranges. A piecewise curved gear ratio map is assumed for all conditions. All analyses are carried out for throttle 'tip-in' condition. The results of the transient dynamic analysis indicate that the transient responses of input and output rollers of the HT-CVU exist when clutch change occurs during vehicle acceleration period from stand still condition. The clutch change also leads to disturbances in the HT-CVU output torque to driveline and in vehicle speed. This leads to imperfect drive feel for the driver. The simulated vehicle velocity indicates powerful acceleration characteristics of the HT-CVU integrated powertrain. Engine harmonics is modelled as a rich collection of various forcing frequencies. These frequencies impress on the response of both the roller and output toroid and are observed in the simulation. Stability analysis is carried out on the powertrain to understand the effect of damping in the tyres and damping within the HT-CVU on the stability of the powertrain. Severe or even unstable response of the HT-CVU takes place if the damping in the HT-CVU and/or the tyres is insufficient during the initial acceleration period and later after the clutch change occurs and when the vehicle is at high speeds. The results of the stability analysis lead us to reason with confidence that the tyre and HT-CVU damping have an effect on the dynamic characteristics and the stability of the system. The response of the powertrain becomes stable when a lock-up clutch is applied over the high speed ranges even if the damping in the tyres remains insufficient. The modal damping ratios for stable and unstable conditions are also discussed. Future investigations need to be carried out in order to understand in depth the fluid-metal interaction in the HT-CVU. This can be achieved by modelling in non-linear drag torque which would act on the HT-CVU elements.

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Stasinopoulos, Peter. "A system dynamics approach to life cycle assessment." Phd thesis, 2013. http://hdl.handle.net/1885/150676.

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Cars consume a large amount of energy and material resources, and generate large environmental impacts, through their production, use, and disposal. Some automotive engineers use the life cycle assessment (LCA) method to estimate and understand these environmental impacts arising from their design decisions. The standard LCA method, however, makes some limiting assumptions that exclude changes in parameter values over time. This lack of the temporal dimension leads to uncertainty in estimates, especially for new, high-volume, long-life products, such as cars. The aim of this thesis is to explore the value and challenges of an LCA method that can account for changes in resource consumptions and environmental impacts over time. This thesis modifies the standard LCA method to include some dynamics-the way that the state of a system changes over time in response to internally-generated and externally-imposed forces. A case study considers the technological intervention of replacing steel with lightweight materials in passenger cars in Australia. It considers the dynamics of the wider 'car system' at the level of the product fleet and resource flows, but not at the level of the environmental impacts. This thesis takes a System Dynamics (SD) approach by developing a computational model, a hypothesis of how the system works. The model explains the growth in the Australian car-fleet fuel consumption despite persistent policy intervention by government to decrease fuel consumption, compliance and technology innovation by car manufacturers, and shifts in transportation preferences to non-car modes by travellers. The model also allows the exploration of future scenarios wherein some car manufacturers adopt lightweight-material components and battery-electric powertrains. The computed values are used in spreadsheet calculations of resource flows and environmental impacts. The simulations of the SD model estimate that many resource benefits of lightweight cars take decades to accumulate because steel cars drain out of the fleet slowly. Furthermore, if the population of car travellers continues to grow, then oil depletion and growth in urban density could cause rapid declines in driving intensity and in the size of the petrol car fleet. Low driving intensity makes it difficult to recover the high energy investment in lightweight materials. Finally, the adoption of battery-electric cars enables car travellers to avoid most effects of oil depletion, but traffic congestion could still cause moderate declines in driving intensity and in the car fleet. The inclusion of the dynamics in an LCA study leads to surprising insights-some computational parameters, usually assumed to be constants or fixed functions of time, are considerably nonlinear. The results of the case study suggest that mass-reduction and similar 'efficiency' interventions are less effective than intended because the balancing loops and buffers of the system prevent parameters from operating in critical ranges that shift feedback loop dominance. The considerable investment into such technological interventions could be redirected, for greater effect, to policy interventions that target fuel security and traffic congestion through the behaviour and decision-making of travellers. The superiority of such interventions can be difficult to identify with a linear worldview of complex systems.

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42

Wiley, Brian. "A low cost AC motor drive for battery powered applications." Thesis, 1993. http://hdl.handle.net/1957/37342.

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Environmental concerns have renewed the interest in electric vehicles. To gain widespread use, electric vehicles will also have to offer good performance and be reasonably priced. AC drive systems using modern semiconductors can provide efficient operation at the required power levels, but their cost at present is still too high. This paper discusses the development of an AC induction motor drive system which potentially lowers cost by using a digital controller. The controller is shown to implement a high performance field-oriented control, while keeping a low parts count by maximizing use of interface circuits which are integrated onto the microprocessor chip. Cost is further reduced by designing the system to reuse motor control components for battery charging and eliminate the need for external circuits. Experimental results are presented for a low power prototype system.
Graduation date: 1994

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43

Javadekar, Virendra S. "Design and development of a controller for a brushless doubly-fed automotive alternator system." Thesis, 1992. http://hdl.handle.net/1957/36918.

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The loads on the electrical systems of automobiles are projected to increase significantly in the near future. This will result in a requirement for improved efficiency over the present-day car alternators. An alternative scheme proposed at Oregon State University employs a Brushless Doubly-Fed Machine (BDFM) as an alternator. This thesis begins with a study and characterization of the existing car alternator system. The configuration of the proposed scheme is discussed. In the proposed configuration, the power winding of the machine generates the bulk of the power and the control winding provides the excitation. The power winding feeds a power rectifier, which in turn charges the battery in an automobile. The control winding is supplied through an inverter. Issues related to inverter and rectifier design are discussed. A 3-phase pulse width modulated inverter and a bridge rectifier were developed and tested for performance. A PSPICE simulation model for the rectifier was developed and results are compared with laboratory tests. A Voltage Regulator Circuit (VRC) and an Efficiency Maximizer Unit (EMU) for the system are designed and developed. A prototype alternator system is tested and the principle of efficiency maximization is verified. Finally. the comparative performance of the the existing and the proposed system is discussed and some recommendations for further improvements in the prototype system are made.
Graduation date: 1992

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44

Finlayson, Adrian Mclean. "The effect of road roughness on vehicle operating costs for medium-sized trucks: a calibration of existing models." Thesis, 1991. https://hdl.handle.net/10539/23779.

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A project report submitted to the faculty of engineering, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the degree of Master of Science in Engineering Johannesburg 1991
In the economic and social development of any country, an effective road transportation system is an important factor However, it also consumes a large proportion of the total infrastructure costs, while the costs borne by the road user for vehicle operation and depreciation arc even greater. A policy must therefore be adopted in which total community costs for any road link Of network are minimized. To do this meaningfully, alternatives must be developed and compared and the trade-offs between them carefully assessed. This, in turn, requires the ability to quantify the different cost functions for the desired period of analysis. [No abstract provided. Information taken from introduction]
MT2018

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45

Desai, Dawood Ahmed. "Prediction and reduction of low-frequency vibro-acoustic transmission through automotive door mounts." 2010. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1000904.

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D. Tech. Mechanical Engineering.
The level and quality of vibration experienced by motor vehicle occupants are issues of increasing concern and will probably be among the major challenges of the automotive industry in the twenty-first century. The vibration behaviour of door panels that enclose the passenger cabin can affect low-frequency noise in the cabin. This thesis presents the theory necessary for the development and simulation of a vibroacoustic door mount system and, thereafter, investigates its potential. Compared to the existing design, a perceivable noise reduction of 6.15 dB(A) was achieved by using the proposed sensitivity analysis procedure.

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46

"An intelligent vehicle security system based on human behaviors modeling." 2006. http://library.cuhk.edu.hk/record=b5892893.

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by Meng Xiaoning.
Thesis (M.Phil.)--Chinese University of Hong Kong, 2006.
Includes bibliographical references (leaves 99-106).
Abstracts in English and Chinese.
Chapter 1 --- Introduction --- p.1
Chapter 1.1 --- Motivation --- p.1
Chapter 1.2 --- Overview --- p.2
Chapter 1.3 --- Organization of the Thesis --- p.3
Chapter 2 --- Related Research --- p.6
Chapter 2.1 --- Information Technology in Cars --- p.6
Chapter 2.2 --- Anti-theft Protection --- p.8
Chapter 2.3 --- Learning Human Behaviors --- p.10
Chapter 2.4 --- Neural Network Learning --- p.11
Chapter 3 --- Experimental Design --- p.14
Chapter 3.1 --- Overview --- p.14
Chapter 3.2 --- Driving Simulation Subsystem --- p.14
Chapter 3.3 --- Data Sensing and Capturing Subsystem --- p.15
Chapter 3.4 --- Data Analysis Subsystem --- p.17
Chapter 4 --- Data Preprocessing for Feature Selection --- p.23
Chapter 4.1 --- Introduction --- p.23
Chapter 4.2 --- Fast Fourier Transform --- p.23
Chapter 4.3 --- Principal Component Analysis --- p.24
Chapter 4.4 --- Independent Component Analysis --- p.26
Chapter 5 --- Classification via Support Vector Machine --- p.28
Chapter 5.1 --- Introduction --- p.28
Chapter 5.1.1 --- Why Using Support Vector Machine --- p.28
Chapter 5.1.2 --- Mathematic Description --- p.29
Chapter 5.2 --- Problem Formulation --- p.31
Chapter 5.3 --- Approach --- p.31
Chapter 5.4 --- Experimental Results --- p.34
Chapter 5.4.1 --- Preprocess Data Analysis --- p.34
Chapter 5.4.2 --- Models Design --- p.37
Chapter 5.5 --- Discussion --- p.44
Chapter 6 --- Evaluation via Hidden Markov Model --- p.47
Chapter 6.1 --- Introduction --- p.47
Chapter 6.1.1 --- Why Using Hidden Markov Model --- p.48
Chapter 6.1.2 --- Mathematic Description --- p.50
Chapter 6.2 --- Problem Formulation --- p.51
Chapter 6.3 --- Approach --- p.53
Chapter 6.4 --- Experimental Results --- p.56
Chapter 6.4.1 --- Model-to-model Measure --- p.56
Chapter 6.4.2 --- Human-to-model Measure --- p.63
Chapter 6.4.3 --- Parameters Optimization --- p.66
Chapter 6.5 --- Discussion --- p.69
Chapter 7 --- System Design and Implementation --- p.71
Chapter 7.1 --- Introduction --- p.71
Chapter 7.2 --- Hardware --- p.72
Chapter 7.3 --- Software --- p.78
Chapter 7.4 --- System Demonstration --- p.80
Chapter 8 --- Conclusion and Future Work --- p.82
Chapter 8.1 --- Contributions --- p.82
Chapter 8.2 --- Future Work --- p.84
Chapter A --- Hidden Markov Model Training --- p.87
Chapter A.1 --- Forward-backward Algorithm --- p.87
Chapter A.2 --- Baum-Welch Algorithm --- p.87
Chapter B --- Human Driving Behavior Data --- p.90
Chapter C --- Publications Resulted from the Study --- p.98

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47

Qhogwana, Xola. "The use of innovative strategies by automotive component manufacturers in Gauteng." Thesis, 2017. http://hdl.handle.net/10321/2560.

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Submitted in fulfilment of the requirements for the degree of Master of Technology in Business Administration: Entrepreneurial Studies & Management, Durban University of Technology, Durban, South Africa, 2017.
The automotive industry is the third largest sector in the South African economy and it plays such an important role in the economy, that it is often viewed used as a barometer of the health of the economy. Despite the relatively large number of automotive component manufacturers (ACMs) in South Africa, manufacturing a wide range of automotive components, and the incentives offered by the government to increase the local content of vehicles manufactured in the country, the majority of vehicle manufacturers as well as after-market wholesalers and retailers in South Africa source a greater proportion of their automotive components from foreign suppliers. This may be due to a number of reasons, and in this regard, this study investigated the nature and extent to which ACMs in Gauteng, South Africa, used innovative strategies to remain competitive. A quantitative research design was used, and a self-administered questionnaire was sent to all of the ACMs located in Gauteng. Some of the main findings from the study was that only 48.9% of the respondents had a Research and Development (R&D) department; ACMs ranked their clients, who include motor vehicle manufacturers and original equipment manufacturers, as the most important source of innovation, with existing employees being ranked second, suppliers ranked third, and competitors ranked fourth. The importance of a highly skilled workforce was highlighted by the finding that almost three quarters of the respondents agreed with the statement that new ideas and suggestions from employees had been implemented. Although the local motor vehicle manufacturers purchase most of the automotive components from ACMs located outside South Africa, the finding that 82% of the ACMs surveyed have been in operation for more than 10 years, with 72% of these organisations in operation for more than 15 years, indicates that most local ACMs are financially profitable and have adapted to global competition.
M

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48

Shinde, Satyajeet Suresh. "Structural Optimization of Thin Walled Tubular Structure for Crashworthiness." Thesis, 2014. http://hdl.handle.net/1805/6104.

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Indiana University-Purdue University Indianapolis (IUPUI)
Crashworthiness design is gaining more importance in the automotive industry due to high competition and tight safety norms. Further there is a need for light weight structures in the automotive design. Structural optimization in last two decades have been widely explored to improve existing designs or conceive new designs with better crashworthiness and reduced mass. Although many gradient based and heuristic methods for topology and topometry based crashworthiness design are available these days, most of them result in stiff structures that are suitable only for a set of vehicle components in which maximizing the energy absorption or minimizing the intrusion is the main concern. However, there are some other components in a vehicle structure that should have characteristics of both stiffness and flexibility. Moreover, the load paths within the structure and potential buckle modes also play an important role in efficient functioning of such components. For example, the front bumper, side frame rails, steering column, and occupant protection devices like the knee bolster should all exhibit controlled deformation and collapse behavior. This investigation introduces a methodology to design dynamically crushed thin-walled tubular structures for crashworthiness applications. Due to their low cost, high energy absorption efficiency, and capacity to withstand long strokes, thin-walled tubular structures are extensively used in the automotive industry. Tubular structures subjected to impact loading may undergo three modes of deformation: progressive crushing/buckling, dynamic plastic buckling, and global bending or Euler-type buckling. Of these, progressive buckling is the most desirable mode of collapse because it leads to a desirable deformation characteristic, low peak reaction force, and higher energy absorption efficiency. Progressive buckling is generally observed under pure axial loading; however, during an actual crash event, tubular structures are often subjected to oblique impact loads in which Euler-type buckling is the dominating mode of deformation. This undesired behavior severely reduces the energy absorption capability of the tubular structure. The design methodology presented in this paper relies on the ability of a compliant mechanism to transfer displacement and/or force from an input to desired output port locations. The suitable output port locations are utilized to enforce desired buckle zones, mitigating the natural Euler-type buckling effect. The problem addressed in this investigation is to find the thickness distribution of a thin-walled structure and the output port locations that maximizes the energy absorption while maintaining the peak reaction force at a prescribed limit. The underlying design for thickness distribution follows a uniform mutual potential energy density under a dynamic impact event. Nonlinear explicit finite element code LS-DYNA is used to simulate tubular structures under crash loading. Biologically inspired hybrid cellular automaton (HCA) method is used to drive the design process. Results are demonstrated on long straight and S-rail tubes subject to oblique loading, achieving progressive crushing in most cases.

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49

Tang, Bo. "Pedestrian Protection Using the Integration of V2V Communication and Pedestrian Automatic Emergency Braking System." Thesis, 2015. http://hdl.handle.net/1805/10057.

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Indiana University-Purdue University Indianapolis (IUPUI)
The Pedestrian Automatic Emergency Braking System (PAEB) can utilize on-board sensors to detect pedestrians and take safety related actions. However, PAEB system only benefits the individual vehicle and the pedestrians detected by its PAEB. Additionally, due to the range limitations of PAEB sensors and speed limitations of sensory data processing, PAEB system often cannot detect or do not have sufficient time to respond to a potential crash with pedestrians. For further improving pedestrian safety, we proposed the idea for integrating the complimentary capabilities of V2V and PAEB (V2V-PAEB), which allows the vehicles to share the information of pedestrians detected by PAEB system in the V2V network. So a V2V-PAEB enabled vehicle uses not only its on-board sensors of the PAEB system, but also the received V2V messages from other vehicles to detect potential collisions with pedestrians and make better safety related decisions. In this thesis, we discussed the architecture and the information processing stages of the V2V-PAEB system. In addition, a comprehensive Matlab/Simulink based simulation model of the V2V-PAEB system is also developed in PreScan simulation environment. The simulation result shows that this simulation model works properly and the V2V-PAEB system can improve pedestrian safety significantly.

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50

Solomon, Cleshain Theodore. "Driver attention and behaviour monitoring with the Microsoft Kinect sensor." Diss., 2015. http://hdl.handle.net/10500/21798.

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Modern vehicles are designed to protect occupants in the event of a crash with some vehicles better at this than others. However, passenger protection during an accident has shown to be not enough in many high impact crashes. Statistics have shown that the human error is the number one contributor to road accidents. This research study explores how driver error can be reduced through technology which observes driver behaviour and reacts when certain unwanted patterns in behaviour have been detected. Finally a system that detects driver fatigue and driver distraction has been developed using non-invasive machine vision concepts to monitor observable driver behaviour.
Electrical Engineering
M. Tech. (Electrical Engineering)

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Дисертації з теми "Automobiles Radiators Design and construction"

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