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Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Physiologie humaine appliquee a l'etude des populations et des conditions de vie. Ecophysiologie humaine, Human physiology applied to population studies and life conditions. Human ecophysiology, Physiologie appliquée, Applied physiology, Transports. Aérospatiale. Plongée. Altitude, Transports. Aerospace. Diving. Altitude, Absorption eau, Water absorption, Absorción agua, Application spatiale, Space application, Aplicación espacial, Chauffage, Heating, Calefacción, Haute température, High temperature, Alta temperatura, Refroidissement eau, Water cooling, Enfriamiento agua, Réfrigération, Refrigeration, Refrigeración, Source chaleur, Heat source, Fuente calor, Vêtement, Clothing, and Vestidura

Future space exploration missions will require a lightweight spacesuit that expends no consumables. This paper describes the design and performance of a prototype heat rejection system that weighs less than current systems and vents zero water. The system uses regenerable LiCl/water absorption cooling. Absorption cooling boosts the heat absorbed from the crew member to a high temperature for rejection to space from a compact, non-venting radiator. The system is regenerated by heating to 100°C for two hours. The system provides refrigeration at 17°C and rejects heat at temperatures greater than 50°C. The overall cooling capacity is over 100 W-hr/kg.

Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines classiques de la physique (y compris les applications), Fundamental areas of phenomenology (including applications), Acoustique, Acoustics, Mesures acoustiques et appareillage, Acoustical measurements and instrumentation, Sciences appliquees, Applied sciences, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Capteur pression, Pressure sensor, Captador presión, Champ intense, High field, Campo intenso, Conception machine, Machine design, Concepción máquina, Coussin sécurité, Air bag, Electronique automobile, Automotive electronics, Electrónica automóvil, Etude expérimentale, Experimental study, Estudio experimental, Mesure accélération, Acceleration measurement, Medición aceleración, Mesure acoustique, Acoustic measurement, and Medida acústica

Zero-offset in transducer output during airbag noise testing is often observed, but mostly ignored due to the lack of understanding of its causes and implications. In the field of high-g acceleration measurement, this phenomenon is well documented, and is referred to as zeroshift. Zero-offset occurs when a component in the measurement chain is exposed to some unexpected inputs which the component has not been designed to handle. These unexpected inputs can be mechanical, electrical, or optical. How the transducer reacts to such inputs and the amount of zero-offset produced depends on the sensing mechanism, material used, and the design of the component itself. This paper explores the causes of zero-offset from a general perspective, covering the entire measurement chain. Although much of the information and discussions are based on data obtained from acceleration measurement systems, the findings are applicable to other transducer types, such as pressure and acoustic measurements.

Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines classiques de la physique (y compris les applications), Fundamental areas of phenomenology (including applications), Mécanique des solides, Solid mechanics, Mécanique des structures et des milieux continus, Structural and continuum mechanics, Sciences appliquees, Applied sciences, Industrie des polymeres, peintures, bois, Polymer industry, paints, wood, Technologie des polymères, Technology of polymers, Formes d'application et semiproduits, Forms of application and semi-finished materials, Matériaux composites, Composites, Metaux. Metallurgie, Metals. Metallurgy, Assemblage et découpage thermique: aspects métallurgiques, Joining, thermal cutting: metallurgical aspects, Soudage, Welding, Acier doux, Mild steel, Acero dulce, Acier haute résistance, High strength steel, Acero alta resistencia, Hochfester Stahl, Automobile, Motor car, Automóvil, Kraftwagen, Carrosserie, Car body, Carrocería, Karosserie, Chassis, Bastidor, Extrusion, Extrusión, Formage, Forming, Conformado, Umformen, Magnésium alliage, Magnesium alloy, Magnesio aleación, Magnesiumlegierung, Matériau composite, Composite material, Material compuesto, Verbundwerkstoff, Métal moulé, Cast metal, Metal moldeado, Gussmetall, Plastique renforcé fibre, Fibre reinforced plastics, Plástico reforzado fibra, Faserverstaerkter Kunststoff, Processus fabrication, Production process, Proceso fabricación, Propriété mécanique, Mechanical properties, Propiedad mecánica, Recherche technique, Technical research, Investigación técnica, Soudage, Welding, Soldadura, and Schweissen

In this paper, the mechanical properties, structural performance and mass saving potential of wrought magnesium alloys are compared to several major automotive materials: mild steel, advanced high-strength steel, cast and wrought aluminum, cast magnesium, plastics and fiber-reinforced composites. Manufacturing processes including welding and joining of magnesium extrusions and sheet products are critically reviewed. The current and potential applications of wrought magnesium alloys in automotive interior, body and chassis areas are discussed. Technical challenges and research opportunities for these applications are identified.

Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Informatique; automatique theorique; systemes, Computer science; control theory; systems, Intelligence artificielle, Artificial intelligence, Reconnaissance des formes. Traitement numérique des images. Géométrie algorithmique, Pattern recognition. Digital image processing. Computational geometry, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Généralités, General, Analyse factorielle, Factor analysis, Análisis factorial, Automobile, Motor car, Automóvil, Conception ingénierie, Engineering design, Concepción ingeniería, Différenciation, Differentiation, Diferenciación, Domaine travail, Workspace, Dominio trabajo, Ergonomie, Ergonomics, Ergonomía, Facteur humain, Human factor, Factor humano, Homme, Human, Hombre, Interface utilisateur, User interface, Interfase usuario, Matrice Jacobi, Jacobi matrix, Matriz Jacobi, Mesure, Measurement, Medida, Modélisation, Modeling, Modelización, Planning installation, Plant layout, Proyecto instalación, Réalité virtuelle, Virtual reality, Realidad virtual, Singularité, Singularity, Singularidad, Solution exacte, Exact solution, Solución exacta, Système temps réel, Real time system, Sistema tiempo real, Temps réel, Real time, Tiempo real, Visualisation, Visualization, and Visualización

Workspace is an important function for human factors analysis and is widely applied in product design, manufacturing, and ergonomics evaluations. This paper presents the workspace analysis and visualization for Santos™ upper extremity, a new virtual human with over 100 DOFs that is highly realistic in terms of appearance, behavior, and movement. Jacobian Rank deficiency method is implemented to determine the singular surfaces. The joint limits are considered in this formulation; three types of singularities are analyzed. This closed-form formulation can be extended to numerous different scenarios such as different percentiles, age groups, or segments of body. A real-time scheme is used to build the workspace library for Santos™ that will study the boundary surfaces off-line and apply them to Santos™ in the virtual environment (Virtools®). To visualize the workspace, we develop a user interface to generate the cross section of the reach envelope with a plane. This is the first step in investigating the zone differentiation; the divided zones based on different human performance measures, and will be helpful in layout design and other human factors analysis.

Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines classiques de la physique (y compris les applications), Fundamental areas of phenomenology (including applications), Mécanique des solides, Solid mechanics, Mécanique des structures et des milieux continus, Structural and continuum mechanics, Vibration, onde mécanique, stabilité dynamique (aéroélasticité, contrôle vibration...), Vibration, mechanical wave, dynamic stability (aeroelasticity, vibration control...), Sciences appliquees, Applied sciences, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Généralités, General, Ajustement modèle, Model matching, Ajustamiento modelo, Analyse corrélation, Correlation analysis, Análisis correlación, Analyse structurale, Structural analysis, Análisis estructural, Angle attaque, Pitch angle, Angulo ataque, Angle incidence, Angle of incidence, Angulo incidente, Automobile, Motor car, Automóvil, Banc essai, Test bench, Banco prueba, Caoutchouc, Rubber, Caucho, Conception machine, Machine design, Concepción máquina, Condition opératoire, Operating conditions, Condición operatoria, Contrainte contact, Contact stress, Tensión contacto, Courbure, Curvature, Curvatura, Défaut, Defect, Defecto, Essai banc, Bench test, Ensayo en el banco, Etude expérimentale, Experimental study, Estudio experimental, Gêne(nuisance), Annoyance, Molestia (rúido), Humidité, Humidity, Humedad, Instabilité, Instability, Inestabilidad, Modélisation, Modeling, Modelización, Optimisation, Optimization, Optimización, Pare brise, Windscreen, Parabrisas, Propreté, Cleanness, Limpieza, Verre, Glass, Vidrio, Vibration, and Vibración

Optimizing the wiper system performance motivates the design engineer to create a product as robust as possible against the occurrence of wipe defects related to vibratory phenomena between the rubber blade and the windshield. In some configurations, these vibrations generate visual or audible annoyance for the driver. These instabilities phenomena only appear under specific operating and environmental conditions characterized by windshield moisture and cleanness, contact pressure of the rubber blade on the glass, attack angle of the wiper blade on the windshield, component stiffness, windshield curvature etc. In the process of eliminating all potential instabilities, modeling the wiper system structures can contribute to understand its working dynamics. Therefore, a new computation tool is developed and validated by experimentation on a specific test bench.

Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Physiologie humaine appliquee a l'etude des populations et des conditions de vie. Ecophysiologie humaine, Human physiology applied to population studies and life conditions. Human ecophysiology, Physiologie appliquée, Applied physiology, Transports. Aérospatiale. Plongée. Altitude, Transports. Aerospace. Diving. Altitude, Course, Running locomotion, Carrera a pie, Coût, Costs, Coste, Gravité, Gravity, Gravedad, Jambe, Leg, Pierna, Locomotion avec jambes, Legged locomotion, Marche à pied, Walking, Caminata, Méthode moindre carré, Least squares method, Método cuadrado menor, Ressort, Spring, and Resorte

In unsuited locomotion, running is more energy efficient than walking, per unit distance and mass, when gravity is less than 0.5g. We analyzed past energetics studies to evaluate whether this finding also applies to locomotion in space suits. We found least-squares fits for cost of transport [J.kg-1.m-1], C, as a function of gravity. Suited C was lower for running at all gravity levels (Earth, Lunar). High suited C during walking likely results from high space suit joint torques; space suit legs, acting as springs during running, achieve low C by improving recovery. Walk-back constraints for planetary extravehicular activity are probably overly conservative and can be reduced to reflect the relative efficiency of running in space suits.

Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Energie, Energy, Energie. Utilisation thermique des combustibles, Energy. Thermal use of fuels, Appareils de production et de conversion d'énergie: énergie thermique, énergie électrique, énergie mécanique, etc, Equipments for energy generation and conversion: thermal, electrical, mechanical energy, etc, Moteurs et turbines, Engines and turbines, Metaux. Metallurgie, Metals. Metallurgy, Corrosion, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Métrologie industrielle. Contrôle, Industrial metrology. Testing, Généralités, General, Organes de machines, Machine components, Frottement, usure, lubrification, Friction, wear, lubrication, Abrasion, Abrasión, Alcool, Alcohol, Alkohol, Automobile, Motor car, Automóvil, Kraftwagen, Banc essai, Test bench, Banco prueba, Carburant moteur, Engine fuel, Carburante motor, Conception machine, Machine design, Concepción máquina, Corrosion, Corrosión, Korrosion, Endommagement, Damaging, Deterioración, Essai abrasion, Abrasion test, Ensayo abrasión, Abrasionsversuch, Essai banc, Bench test, Ensayo en el banco, Essence auto, Motor gasoline, Gasolina coche, Ethanol, Etanol, Aethanol, Etude expérimentale, Experimental study, Estudio experimental, Experimentelle Untersuchung, Lubrification, Lubrication, Lubricación, Schmieren, Microscopie électronique balayage, Scanning electron microscopy, Microscopía electrónica barrido, Rasterelektronenmikroskopie, Moteur combustion interne, Internal combustion engine, Motor explosión interna, Moteur essence, Gasoline engine, Motor bencina, Benzinmotor, Métrologie surface, Surface metrology, Metrología superficie, Pompe engrenage, Gear pump, Bomba encaje, Pompe électrique, Electric pump, Bomba eléctrica, Profilométrie, Profilometry, Perfilometría, Profilometrie, Propriété lubrifiante, Lubricity, Propiedad lubricante, Tribologie, Tribology, Tribología, Usure abrasive, Abrasive wear, Desgaste abrasivo, Abrasivverschleiss, Usure corrosive, Corrosive wear, Desgaste corrosivo, and Korrosiver Verschleiss

The automotive electrical fuel pumps for gasoline and alcohol fueled vehicles engines are lubricated by the fuel itself. The new flexible fuel engine technology, specially in Brazil, the fuel pump is designed to be lubricated by gasohol (E22) or strait hydrated ethanol fuel but it is also exposed to the variable gasoline/alcohol blends in the flex-fuel engines. This paper presents the influence of different fuel blends, ethanol and gasohol, to the fuel pump wear and corrosion behaviors. The tested fuel pumps were designed for gasohol only engines. The fuel pumps were tested in a bench device, which simulates the vehicle fuel circuit, using gasohol (E22), hydrated ethanol (E100) or 60 % in volume ethanol-gasoline mixture (E60). The scanning electron microscopy examinations and roughness measurements were performed for tribological analysis of fuel pump gears. The observed wear and/or other deterioration mechanisms were mainly due to the abrasion and corrosion. The tests showed that abrasion mechanisms were more pronounced in the E22 fuel and the corrosion mechanisms were more damaging in the E60 and E100 fuels. The fuel pumps gears lubrication regime was calculated and the tested fuels lubricities were also measured.

Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines classiques de la physique (y compris les applications), Fundamental areas of phenomenology (including applications), Acoustique, Acoustics, Acoustique des structures et vibration, Structural acoustics and vibration, Bruit: ses effets et son contrôle, Noise: its effects and control, Sciences appliquees, Applied sciences, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Acoustique structurale, Structural acoustics, Ruido transmitido estructura, Analyse statistique, Statistical analysis, Análisis estadístico, Approche probabiliste, Probabilistic approach, Enfoque probabilista, Automobile, Motor car, Automóvil, Bruit impulsion, Pulse noise, Ruido impulso, Enregistrement son, Sound recording, Registro sonido, Evaluation subjective, Subjective evaluation, Evaluación subjetiva, Modélisation, Modeling, Modelización, Métrique, Metric, Métrico, Qualité sonore, Sound quality, Calidad sonora, Roue libre, Free wheel, Rueda libre, Réponse impulsion, Pulse response, Respuesta impulsión, Seuil perception, Perception threshold, Umbral percepción, Source sonore, Sound source, Fuente sonora, Transformation ondelette, Wavelet transformation, Transformación ondita, Transmission mécanique, Mechanical drive, and Transmisión mecánica

A wavelet-based technique for reducing the impulsive character of sound recordings is presented. The amount of impulsive content removed may be adjusted by varying a statistical threshold. The technique is validated for a diesel idle sound-quality application. The wavelet-based modification produces a substantial decrease in impulsive character as verified by an objective sound-quality metric for engine ticking. Informal subjective assessment of the modified results found them to be realistic and free from artifacts. The procedure is expected to be useful for sound-quality simulation and target-setting for diesel powertrain noise and other automotive sounds containing both impulsive and non-impulsive content.

Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines classiques de la physique (y compris les applications), Fundamental areas of phenomenology (including applications), Mécanique des fluides, Fluid dynamics, Ecoulement rotationnel et vorticité, Rotational flow and vorticity, Aile, Wing, Ala, Aérodynamique, Aerodynamics, Battement alaire, Wing beat, Aleteo, Bord attaque, Leading edge, Borde ataque, Bord fuite, Trailing edge, Borde salida, Décrochage écoulement, Stall, Desprendimiento flujo, Détachement tourbillonnaire, Vortex shedding, Desprendimiento vorticial, Ecoulement critique, Critical flow, Ecoulement instationnaire, Unsteady flow, Ecoulement tourbillonnaire, Vortex flow, Etude expérimentale, Experimental study, Instabilité hydrodynamique, Hydrodynamic instability, Modélisation, Modelling, Sillage, Wakes, Structure turbulence, Turbulence structure, Estructura turbulencia, Tourbillon, Vortices, Visualisation écoulement, Flow visualization, Vélocimétrie image particule, Particle image velocimetry, Microaéronef, Micro air vehicle, and Microaeronave

Experiments were performed to better understand the aerodynamic flow field of a flapping-wing micro air vehicle. High-resolution laser sheet flow visualization and particle image velocimetry (PIV) analyses have shown the presence of folded vortex filaments that are trailed from the tip and root of the wing, which are combined with a shed dynamic stall vortex with a strong spanwise flow toward the wing tip. This leading-edge vortex gains strength as the translational motion of the wing accelerates through midstroke. There is a subsequent shedding of this vortex, but with the simultaneous formation of another leading-edge vortex. The generation of the second vortex occurs before the first vortex reaches mid-chord, enhancing overall lift. This second vortex moves along the chord during supination, before finally being shed from the trailing-edge of the wing. A starting vortex forms near the trailing-edge as the wing starts to accelerate during the downstroke/upstroke of the flapping cycle. This starting vortex grows larger in size, gaining energy from further shed vortices, until the wing reaches the mid-point of the cycle. The folded root and tip vortices that trail from the flapping wing have been found to be relatively strong, and move inward and axially downward as the wing moves through its flapping cycle. The close proximity of the starting vortex, as well as the trailed root and tip vortices, has a large influence on the downwash over the wing. This suggests that any modeling techniques used to predict the lift on flapping wings must fundamentally take into account the three-dimensional, unsteady effects associated with its complex vortex wake structure.

Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines classiques de la physique (y compris les applications), Fundamental areas of phenomenology (including applications), Mécanique des fluides, Fluid dynamics, Théorie générale, General theory, Ecoulements turbulents, convection et transfert de chaleur, Turbulent flows, convection, and heat transfer, Ecoulement rotationnel et vorticité, Rotational flow and vorticity, Dynamique de tourbillon, Vortex dynamics, Sciences appliquees, Applied sciences, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Analyse statistique, Statistical analysis, Approche probabiliste, Probabilistic approach, Enfoque probabilista, Automobile, Automobiles, Aérodynamique, Aerodynamics, Echelle grande, Large scale, Escala grande, Ecoulement instationnaire, Unsteady flow, Ecoulement irrotationnel, Irrotational flow, Flujo irrotacional, Ecoulement tourbillonnaire, Vortex flow, Ecoulement turbulent, Turbulent flow, Etude expérimentale, Experimental study, Grille, Grids, Modélisation, Modelling, Structure turbulence, Turbulence structure, Estructura turbulencia, Tourbillon, Vortices, Vorticité, Vorticity, Véhicule routier, and Road vehicles

Recent results are presented from the application of a grid-free vortex method to the prediction of turbulent aerodynamic flows produced by road vehicles. The approach has the character of a large eddy simulation and incorporates a fast technique for evaluating the mutual interactions of several million vortex elements needed in describing the dynamically significant structure of the turbulent field. The simulations provide information about the unsteady evolution of the flow including forces, vortical structure and separation regions. Predicted mean velocity statistics are shown to compare favorably with physical experiments.

Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Aile, Wing, Ala, Automobile, Motor car, Automóvil, Condition stationnaire, Stationary condition, Condición estacionaria, Corps arête vive, Bluff body, Cuerpo arista viva, Ecoulement tourbillonnaire, Swirling flow, Flujo torbellinal, Effet sol, Ground effect, Efecto suelo, Frottement superficiel, Skin friction, Frotamiento superficial, Jeu mécanique, Mechanical clearance, Juego mecánico, Modélisation, Modeling, Modelización, Portance, Lift, Fuerza sustentación, Tourbillon, Vortex, Torbellino, Traînée aérodynamique, Aerodynamic drag, Arrastre aerodinámico, Véhicule routier, Road vehicle, and Vehículo caminero

Aerodynamic drag is comprised of pressure drag and skin friction only. The drag component associated with lift forces is contained within these two terms. In the case of a simple wing this drag component, called induced drag, is reasonably well defined as a function of lift, but for road vehicles the relationship is more complex. In this paper the drag due to lift, which will be called vortex drag, is investigated for a simple car-like shape at incidence in proximity to the ground. The vortex drag is derived from the parabolic relationship between drag and lift. The effects of ground clearance are considered for both moving a stationary ground simulations. The results are compared with data for other simple bodies.

Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Metaux. Metallurgie, Metals. Metallurgy, Assemblage et découpage thermique: aspects métallurgiques, Joining, thermal cutting: metallurgical aspects, Soudage, Welding, Condition opératoire, Operating conditions, Condición operatoria, Etude expérimentale, Experimental study, Estudio experimental, Experimentelle Untersuchung, Industrie automobile, Automobile industry, Industria automóvil, Autoindustrie, Industrie aérospatiale, Aerospace industry, Industria aeroespacial, Raumfahrtindustrie, Marqueur, Marker, Marcador, Modélisation, Modeling, Modelización, Soudage friction, Friction welding, Soldeo por fricción, Reibschweissen, Soudage par points, Spot welding, Soldadura punto, Visualisation, Visualization, and Visualización

Friction Stir Spot Welding (FSSW) has a strong potential to find applications in both the automotive and aerospace industries. At the present time, research efforts are taking place to gain a better understanding of the process, to explore different tool configurations, and to optimize the set of process parameters. In this regard, gaining an understanding of how the material flows under a given set of processing parameters is of particular importance for tool design and to validate numerical models aimed at simulating the process. In this paper, the results corresponding to an experimental study performed using markers are presented to provide insight about the material flow during the plunge phase of the fixed-position refill FSSW process.

Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Analyse performance, Performance analysis, Análisis eficacia, Automobile, Motor car, Automóvil, Direction véhicule, Vehicle direction, Dirección vehículo, Essai qualification, Prototype tests, Prueba calificación, Innovation, Innovación, Modélisation, Modeling, Modelización, Méthode élément fini, Finite element method, Método elemento finito, Roue, Wheel, Rueda, Système protection, Protection system, Sistema protección, Volant, Steering wheel, and Volante dirección

A steering wheel is an indispensable component in an automobile. Although the steering wheel was invented about one hundred years ago and its structure has since become more and more complex with numerous innovations, documented analysis on steering wheel performance is very limited. Today, a steering wheel is not only a wheel that controls where your car goes; it also plays an important role in a vehicle occupant protection system. Therefore, many requirements have to be met before a steering wheel goes into production. With the development of computational mechanics and increasing computer capability, it has become much easier to evaluate the steering wheel performance in a totally different way. Instead of running prototype tests, steering wheel designs can be modeled virtually in various scenarios using finite element analysis, thus facilitating the development cycle. The objective of this paper is to give an overview of the modeling, simulation and challenges faced in the analysis of steering wheels.

Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Constructions métalliques, Steel design, Tuyauteries, vannes, robinetteries, Pipings, valves, fittings, Analyse multirésolution, Multiresolution analysis, Análisis multiresolución, Automobile, Motor car, Automóvil, Canalisation, Pipe, Canalización, Conception assistée, Computer aided design, Concepción asistida, Conduite horizontale, Horizontal pipe, Conducto horizontal, Norme, Standards, Norma, Problème agencement, Layout problem, Problema disposición, Réalité virtuelle, Virtual reality, Realidad virtual, Théorie rayon, Ray theory, Teoría rayo, Traitement numérique, Digital processing, Tratamiento digital, Transmission multicanal, Multichannel transmission, Transmisión multicanal, Tube cathodique, Cathode tube, Tubo catódico, Tube horizontal, Horizontal tube, Tubo horizontal, Tuyauterie, Piping, and Cañería

Since February 1999, GM Design Center has used a 3 wall Virtual Reality (VR) Studio to evaluate new design themes and alternative ideas and concepts. This paper provides information on the major uses of VR at Design Center and technical details on the changes in the equipment and layout of the VR Studio as customer needs and software have evolved. We trace the development from stacked, standard analog horizontal Cathode Ray Tube (CRT) projectors to vertically mounted digital CRT's for higher resolution, and finally to the current use of Digital Light Processing (DLP) projectors mounted between the digital CRT's. This last combination has essentially provided two VR rooms in one physical space - one for high-resolution math evaluation using multi-pipe, multichannel software and the second for evaluating 2D sketches and single channel WindowsTM based CAD/CAE applications.

Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Architecture logiciel, Software architecture, Automobile, Motor car, Automóvil, Développement logiciel, Software development, Desarrollo logicial, Electronique automobile, Automotive electronics, Electrónica automóvil, Ingénierie système, Systems engineering, Système sécurité, Safety systems, Transmission mécanique, Mechanical drive, Transmisión mecánica, Unité contrôle, Control unit, and Unidad control

Automotive powertrain and safety systems under design today are highly complex, incorporating more than one CPU core, running with more than 100 MHz and consisting of several 10 million transistors. Software complexity increases similarly making new methodologies and tools mandatory to manage the overall system. The use of accurate virtual prototypes improves the quality of systems with respect to system architecture design and software development. This approach is demonstrated with the example of the PCP/GPTA subsystem for Infineon's AUDO-NG powertrain controllers.

Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines classiques de la physique (y compris les applications), Fundamental areas of phenomenology (including applications), Acoustique, Acoustics, Acoustique des structures et vibration, Structural acoustics and vibration, Mécanique des solides, Solid mechanics, Mécanique des structures et des milieux continus, Structural and continuum mechanics, Vibration, onde mécanique, stabilité dynamique (aéroélasticité, contrôle vibration...), Vibration, mechanical wave, dynamic stability (aeroelasticity, vibration control...), Sciences appliquees, Applied sciences, Informatique; automatique theorique; systemes, Computer science; control theory; systems, Automatique théorique. Systèmes, Control theory. Systems, Synthèse des systèmes de commande, Control system synthesis, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Acoustique structurale, Structural acoustics, Ruido transmitido estructura, Automobile, Motor car, Automóvil, Conception ingénierie, Engineering design, Concepción ingeniería, Large bande, Wide band, Banda ancha, Localisation, Localization, Localización, Marché, Markets, Mercado, Modélisation, Modeling, Modelización, Méthode optimisation, Optimization method, Método optimización, Méthode élément fini, Finite element method, Método elemento finito, Méthode élément frontière, Boundary element method, Método elemento frontera, Nervure, Rib, Nervadura, Optimisation, Optimization, Optimización, Plaque, Plate, Placa, Processus conception, Design process, Proceso concepcion, Rayonnement acoustique, Acoustic radiation, Radiación acústica, Synthèse commande, Control synthesis, Síntesis control, Vibration, and Vibración

The Noise, Vibration, Harshness (NVH) behavior is one of the predominant factors for market acceptance of vehicles. As to thin parts in the automobiles, the effect result of rib stiffening can significantly alter noise and vibration character of the plate. In this paper, the location and the dimensions of two cross stamped ribs in a plate have been optimized to minimize the radiated noise power under broad-band excitation. The objective of the study is to determine effective design methods for vibroacoustic optimization of the ribs in a plate. The reconstruction of the finite element model and the boundary model in the optimization iterations is one of key factors. Radiated sound power is calculated using a boundary element method, with a finite element solver ANSYS for the solution of the structural vibration.

Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines classiques de la physique (y compris les applications), Fundamental areas of phenomenology (including applications), Acoustique, Acoustics, Acoustique des structures et vibration, Structural acoustics and vibration, Sciences appliquees, Applied sciences, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Acoustique structurale, Structural acoustics, Ruido transmitido estructura, Aimant permanent, Permanent magnet, Imán permanente, Analyse modale, Modal analysis, Análisis modal, Appui élastique, Elastic support, Apoyo elástico, Automobile, Motor car, Automóvil, Coque mince, Thin shell, Cascarón delgado, Couche mince, Thin film, Capa fina, Distraction, Distracción, Divertissement, Entertainment, Electronique automobile, Automotive electronics, Electrónica automóvil, Etude expérimentale, Experimental study, Estudio experimental, Film plastique, Plastic film, Película plástica, Frottement interne, Internal friction, Frotamiento interno, Locuteur, Speaker, Locutor, Modification structure, Structure modification, Modificación estructural, Méthode potentiel, Potential method, Método potencial, Méthode élément fini, Finite element method, and Método elemento finito

One potential method by which to realize better acoustic in-car entertainment with a minimum of space is to adopt very thin Flat-Panel Speakers (FPSs), which use a combination of an array of coils printed on a flexible thin plastic film and permanent magnets. In the present report, the optimal panel material was investigated through experimental modal analysis. The optimal driving unit placement over the board was then determined using FEM based modal analyses. Finally, structural modifications to the sound radiating board in order to obtain a wider efficient frequency range were investigated experimentally. Among several design alternatives, satisfactory results were obtained by either dividing the sound radiating board into virtually independent sub-panels or adding resilient damping material supported by a restraining material.

Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Physique, Physics, Domaines classiques de la physique (y compris les applications), Fundamental areas of phenomenology (including applications), Acoustique, Acoustics, Acoustique des structures et vibration, Structural acoustics and vibration, Mécanique des solides, Solid mechanics, Mécanique des structures et des milieux continus, Structural and continuum mechanics, Vibration, onde mécanique, stabilité dynamique (aéroélasticité, contrôle vibration...), Vibration, mechanical wave, dynamic stability (aeroelasticity, vibration control...), Méthodes de mesure et d'essai, Measurement and testing methods, Sciences appliquees, Applied sciences, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Transmissions, Drives, Arbres, accouplements, embrayages, freins, Shafts, couplings, clutches, brakes, Acoustique structurale, Structural acoustics, Ruido transmitido estructura, Automobile, Motor car, Automóvil, Basse fréquence, Low frequency, Baja frecuencia, Catégorisation, Categorization, Categorización, Cavité, Cavity, Cavidad, Condition aux limites, Boundary condition, Condiciones límites, Condition opératoire, Operating conditions, Condición operatoria, Durabilité, Durability, Durabilidad, Freinage, Braking, Frenado, Mesure vibration, Vibration measurement, Mode vibration, Vibrational mode, Modo de vibración, Modèle dynamique, Dynamic model, Modelo dinámico, Modélisation, Modeling, Modelización, Moyenne fréquence, Medium frequency, Frecuencia media, Méthode élément fini, Finite element method, Método elemento finito, Nombre onde, Wave number, Número onda, Pneumatique, Tyre, Neumático, Roue, Wheel, Rueda, Vibration radiale, Radial vibration, Vibración radial, Vibromètre, Vibrometer, and Vibrómetro

The use of tire vibration modes to represent dynamics in tire models has grown significantly over the years. Initially used primarily in tire modal models to simulate low- to mid-frequency range structure-borne Noise, Vibration, and Harshness (NVH), the applications have broadened to higher frequency, air-borne NVH, and more recently to durability, ride, and braking performance simulations. The broadness and growing importance of these applications lend to having a unified understanding of tire modes and their significance to simulation quality. To this end, a naming convention using wave numbers is developed to identify and categorize modes of an unloaded tire. Background on measurement and predictive tools is presented. Finite element method models are used for interpreting the wave number concept to the 3-D mode shapes and to account for dynamics of the wheel and enclosed air cavity. The effect of tire construction changes on families of modes is discussed throughout. The intent is to simplify and improve identification and physical understanding of tire vibration modes, measurement and simulation techniques and quality, and communication among NVH specialists as well as non-NVH analysts.

Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Automobile, Motor car, Automóvil, Développement logiciel, Software development, Desarrollo logicial, Etude expérimentale, Experimental study, Estudio experimental, Génération automatique, Automatic generation, Generación automatica, Industrie automobile, Automobile industry, Industria automóvil, Main, Hand, Mano, Modélisation, Modeling, and Modelización

Currently in the automotive industry, most software source code is manually generated (i.e., hand written). This manually generated code is written to satisfy requirements that are generally specified or captured in an algorithm document. However, this process can be very error prone since errors can be introduced during the manual translation of the algorithm document to code. A better method would be to automatically generate code directly from the algorithm document. Therefore, the automotive industry is striving to model new and existing algorithms in an executable-modeling paradigm where code can be automatically generated. The advent of executable models together with automatic code generation should allow the translation of model to code to be error free, and this error-free status can be confirmed through testing. A three-stage process is presented to functionally verify the model, functionally verify the automatically-generated code, and structurally verify the code.

Mechanical engineering, Génie mécanique, Metallurgy, welding, Métallurgie, soudage, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Genie mecanique. Construction mecanique, Mechanical engineering. Machine design, Architecture basée modèle, Model driven architecture, Arquitectura basada modelo, Automobile, Motor car, Automóvil, Chassis, Bastidor, Châssis véhicule, Vehicle chassis, Chasis vehículo, Dynamique véhicule, Vehicle dynamics, Dinámica vehículo, Electronique automobile, Automotive electronics, Electrónica automóvil, Fiabilité, Reliability, Fiabilidad, Modélisation, Modeling, Modelización, Oscillation lacet, Yawing, Movimiento lazo, Pilotage ordinateur, Computer control, Control por ordenador, Roulis, Roll, Balanceo, Sécurité, Safety, Seguridad, Commande dynamique, dynamic control, and Comando dinámico

As the complexity of automotive chassis control systems increases with the introduction of technologies such as yaw and roll stability systems, processes for model-based development of chassis control systems becomes an essential part of ensuring overall vehicle safety, quality, and reliability. To facilitate such a model-based development process, a vehicle modeling framework intended for chassis control development has been created. This paper presents a design methodology centered on this modeling framework which has been applied to real world driving events and has demonstrated its capability to capture vehicle dynamic behavior for chassis control development applications.