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In this study, we propose a method of measuring and analyzing the load on bolted joints used in a machine under off-road vehicle operation. Working load measurement under actual machine operation and the results of its analysis are shown as load frequency diagrams. An example of the measurement analysis of a load (three types of load: axial force, bending moment, and torsional torque) added to a bolted joint shank during actual machine operation is shown. In this paper, we describe how to apply the results of load analysis to the load condition at the design and experimental development stages.

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 realtime 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.

The Two-Stroke engine revival is seen as a way to reduce the size and weight of engines. IFP has been one of the first engine research centres involved since the early eighties in this promising way of a new generation of highly efficient engines. Since this date, a large number of car manufacturers and research laboratories around the world have engaged research and development efforts in this new field. In these conditions, it was essential for IFP to examine the different research works, technological choices, and new ideas. The systematic study of the patents published since 1981 and their statistical analysis represent an interesting tool to follow the main trends of the research in this domain. More than 4200 patents were selected as relevant for this study.

For every export oriented automobile manufacturer it is necessary to have an exact knowledge of the operating profiles of his vehicles. Only with this know-how is it possible to find the best design to meet the requirements of marketing, manufacturing, finance and economy Typical for this design concept is our Kadett: World-wide road tests with comprehensive data acquisition and data evaluation have been conducted to determine the operating profiles for various countries and continents (Europe, United States, Australia, South Africa, Brasil). The achieved results serve as an experimental basis for Single-and Multiaxial Real-Time Service Load Simulations of components, subsystems or complete vehicles in consideration of an optimum fatigue life prediction and an economical test management. Finally the importance of the test correlation between road and laboratory tests as a world-wide task in automotive industry will be shown.

The purpose of this paper is to review and summarize recent trends around the world regarding diesel vehicles, the health effects associated with diesel particulate, and the actions taken by governments to reduce these emissions. Further, the paper will summarize manufacturer efforts to develop control technologies for diesel particulate.

Most of the major industrialized areas of the world have been experiencing serious motor vehicle pollution problems over the last decade. The motor vehicle pollution control programs which have have been developed to deal with the effects have led to tremendous advances in gasoline car control technologies. Similar technologies are under intensive development for diesel cars and trucks. Several developing countries are now experiencing similar air pollution problems. This paper surveys the most recent data regarding adverse environmental impacts resulting from motor vehicles, reviews technologies developed to address these problems, and summarizes the current status around the world.

An international standard for nonroad engines has been developed that comprises gaseous and particulate emissions measurement procedures, smoke testing, test cycles, and an engine family and group concept. Through a joint effort of industry and government agencies, ISO 8178 has become the basis for emissions legislation in the USA, the European Union and Japan and of the International Maritime Organization. The ultimate goal of worldwide harmonization for the worldwide engine industry has been reached, but much effort is still needed to maintain the level of harmonization achieved today. The validity of ISO 8178 has been demonstrated on a round robin test with three engines of 19 to 170 kW circulated around 28 test laboratories. Test-to-test repeatability was generally lower than 10 %. Lab-to-lab variability was less than 10 % for NOx and particulates, and over 25 % for HC and CO. The equivalence of partial flow and full flow dilution systems for particulates has been proven.

This paper reviews the trend in worldwide exhaust emission regulations for heavy-duty diesel engines and common key technologies that must be developed and applied in order to meet these regulations. The common key technologies are intake and exhaust system with turbocharger and intercooler, electronically controlled high-pressure fuel injection system, exhaust gas recirculation, and exhaust gas after-treatment devices. This paper also introduces test results of common key technologies, concepts for low-emission heavy-duty diesel engines, and the possibilities for meeting future exhaust emission legislation is described.

Abstract Autonomous vehicles (AVs) rely heavily upon their perception subsystems to “see” the environment in which they operate. Unfortunately, the effect of variable weather conditions presents a significant challenge to object detection algorithms, and thus, it is imperative to test the vehicle extensively in all conditions which it may experience. However, the development of robust AV subsystems requires repeatable, controlled testing—while real weather is unpredictable and cannot be scheduled. Real-world testing in adverse conditions is an expensive and time-consuming task, often requiring access to specialist facilities. Simulation is commonly relied upon as a substitute, with increasingly visually realistic representations of the real world being developed.

The current test methods are insufficient to evaluate and ensure the safety and reliability of vehicle system for all possible dynamic situations including the worst cases such as rollover, spin-out and so on. Although the known NHTSA J-turn and Fish-hook steering maneuvers are applied for the vehicle performance assessment, they are not enough to predict other possible worst case scenarios. Therefore, it is crucial to search for the various worst cases including the existing severe steering maneuvers. This paper includes the procedure to search for other useful worst case based upon the existing worst case scenarios in terms of rollover and its application in simulation basis. The human steering angle is selected as a design variable and optimized to maximize the index function to be expressed in terms of vehicle roll angle. The obtained scenarios were enough to generate the worse cases than NHTSA ones.

One of the key premises of the ISO 26262 functional safety standard is the development of an appropriate Technical Safety Concept for the item under development. This is specified in detail in Part 4 of the standard - Product development at the system level. The Technical safety requirements and the technical safety concept form the basis for deriving the hardware and software safety requirements that are then used by engineering teams for developing a safe product. Just like any other form of product development, making multiple revisions of the requirements are highly undesirable. This is primarily due to cost increases, chances of having inconsistencies within work products and its impact on the overall project schedule. Good technical safety requirements are in fact the foundation for an effective functional safety implementation.

This Report presents general information on over 50 alloys in which nickel either predominates or is a significant alloying element. It covers primarily wrought materials, and is not necessarily all inclusive. Values given are in most cases average or nominal, and if more precise values are required the producer(s) should be contacted. This report does not cover the so-called "superalloys," or the iron base stainless steels. Refer to SAE J467, Special Purpose Alloys, and SAE J405, Chemical Compositions of SAE Wrought Stainless Steels, respectively, for data on these alloys.

This paper deals with the problem of complex engine part analysis. It presents an original approach based on the use of X-ray Computed Tomography scan digitizing method. In comparison with classical digitizing method, Computed Tomography method proves to be the only solution in the case of complex parts with internal areas. A validation example for which the precision of the method is estimated, is proposed. At last, the potential of the method is illustrated through the complex example of an engine head cooling circuit for which a computational CFD calculation is made.

The sparking behavior in an internal combustion engine affects the fuel efficiency, engine-out emissions, and general drivability of a vehicle. As emissions regulations become progressively stringent, combustion strategies, including exhaust gas recirculation (EGR), lean-burn, and turbocharging are receiving increasing attention as models of higher efficiency advanced combustion engines with reduced emissions levels. Because these new strategies affect the working environment of the spark plug, ongoing research strives to understand the influence of external factors on the spark ignition process. Due to the short time and length scales involved and the harsh environment, experimental quantification of the deposited energy from the sparking event is difficult to obtain. In this paper, we present the results of x-ray radiography measurements of spark ignition plasma generated by a conventional spark plug.

The salient features of modern gasoline direct injection include cavitation, flash boiling, and plume/plume interaction, depending on the operating conditions. These complex phenomena make the prediction of the spray behavior particularly difficult. The present investigation combines mass-based experimental diagnostics with an advanced, in-house modeling capability in order to provide a multi-faceted study of the Engine Combustion Network’s Spray G injector. First, x-ray tomography is used to distinguish the actual injector geometry from the nominal geometry used in past works. The actual geometry is used as the basis of multidimensional CFD simulations which are compared to x-ray radiography measurements for validation under cold conditions. The influence of nozzle diameter and corner radius are of particular interest. Next, the model is used to simulate flash-boiling conditions, in order to understand how the cold flow behavior corresponds to flashing performance.

Cavitation plays a significant role in high pressure diesel injectors. However, cavitation is difficult to measure under realistic conditions. X-ray phase contrast imaging has been used in the past to study the internal geometry of fuel injectors and the structure of diesel sprays. In this paper we extend the technique to make in-situ measurements of cavitation inside unmodified diesel injectors at pressures of up to 1200 bar through the steel nozzle wall. A cerium contrast agent was added to a diesel surrogate, and the changes in x-ray intensity caused by changes in the fluid density due to cavitation were measured. Without the need to modify the injector for optical access, realistic injection and ambient pressures can be obtained and the effects of realistic nozzle geometries can be investigated. A range of single and multi-hole injectors were studied, both sharp-edged and hydro-ground. Cavitation was observed to increase with higher rail pressures.

The experimental XA-100 is a 5-passenger 4-door Chevrolet Corsica that has been retrofitted with an electric-motor propulsion system, batteries, and an on-board engine/alternator system. The XA-100 is designed 1) to travel on around-town and short freeway commute trips on battery power alone with zero exhaust emissions (zero-emissions vehicle (ZEV)) and 2) to travel as an ultra-low-emissions vehicle (ULEV) on long distance trips using an on-board engine/alternator (i.e., an auxiliary power unit (APU)) for electric power. In all other respects (e.g., performance, handling, user interface), the XA-100 is designed to retain the characteristics of the conventional Corsica to the greatest degree possible. The XA-100 was developed as a result of research sponsored in part by the California Energy Commission (CEC), with labor donated by members of the Electric Auto Association (EAA) and faculty, staff and students of Stanford University.

HID as lightsource in the automotive world has been proven as the most efficient way to satisfy the main user's requirements on a headlighting bulb: Realize a broad beam pattern with superior performance on visibility, safety and comfort on the one hand, and the fulfillment of long lifetime requirements on the other hand. In the second step, the logical integration of functions and the improvement of automotive system requests such as size and EMC has to be covered. An integrated bulb with starter is the appropriate way to combine these features: Optimized fine tuning between the entire lightsource and the starter to reach optimal electrical and EMI performance on the one side on the other side combined with very compact sizes leads to an automotive source perfectly suiting to the modern trends in headlighting applications.

From mohair plush to woolens, to patterns and now synthetics - that's the growth of automotive fabrics. The 1956 models have gig-finished woolen system broadcloths, tweeds made with spun yarns, Jacquards with spun and filaments, dobby patterns on both woolen and worsted systems and a wide use of boucle or novelty yarns. Fabric designing has become a highly specialized art, attuned always to the stylists' demands. Abrasion, dye stability and light fastness, durability, shrinkage and stretch, cost, spotting and water repellency are all important factors. Where physical requirements are about the same from all automobile manufacturers, they greatly vary in interpretations of results. Where do we go from here? There are synthetics yet untried; some may be blended with natural fibers. By taking the textile supplier more into their confidence, automobile builders would help chart the course ahead.

In the current Ford Pro-Trailer Backup Assist (TBA) system, trailer hitch angle is determined utilizing the reverse camera of the vehicle. In addition to being sensitive to environmental factors such as lighting conditions and occlusion, the vision-based approach is difficult to be applied to gooseneck or fifth wheel trailers. In this paper, a yaw rate based hitch angle observer is proposed as an alternative sensing solution for TBA. Based on the kinematic model of the vehicle-trailer, an instantaneous hitch angle is first derived by utilizing vehicle yaw rate, trailer yaw rate, vehicle velocity and vehicle/trailer parameters provided by the TBA system. Due to signal errors and parameter uncertainties, this instantaneous hitch angle may be noisy, especially at lower vehicle speed.