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In motorcycles, the materials of frame have been switched from steel to aluminum for the purpose of reducing weight while improving the rigidity of chassis. It was made possible to use aluminum frames for a number of commodity categories, by the development of technology through new structural designs to make the most of the characteristics of aluminum, the advancement of computer simulation system and the progress in material and production engineering. As the result of adopting aluminum for the frame, much higher performance has been realized by achieving a 40% reduction in the developed frames consisting of extrusions and castings for sports-oriented motorcycles and by suppressing the increase in fuel consumption. For low-priced utility vehicles such as scooters, the manufacturing process has been simplified by the development of the die cast two-split module frame.

International Truck has launched a solution using telematics technology to deliver advanced applications and services to the commercial trucking industry. As the company moved from strategy to execution we discovered a number of “transformations” that needed to occur in order for all parties (International, our customers, dealers, and partners) to maximize potential benefits. This paper describes this journey and the impact technology can have on a traditional manufacturing company's ability to differentiate its products.

For the major automakers to make the decision for a paradigm shift to hydrogen as a transportation fuel in the future, they need to be assured of the development of the infrastructure to accelerate their initiative. A hydrogen infrastructure must be in put in place to meet the demand for hydrogen fuel by fuel cell vehicles. In the absence of an adequate hydrogen-refueling infrastructure, Quantum Fuel Systems Technologies Worldwide, Inc. has developed modular, portable, and transportable hydrogen refueling systems to support early introduction fuel cell vehicles when and where needed. This paper describes selected hydrogen refueling systems and their application.

California's experience with fuel methanol holds lessons for infrastructure development efforts for other alternative fuels and suggests strategic approaches for developing future infrastructure to serve dedicated vehicles: 1. Vehicle/engine capability to utilize “dedicated” (neat) fuels in a fuel-flexible mode; this requires large investments to meet initially small markets. 2. “Strategic dispersal”, placing stations along primary transportation corridors and in “target areas” determined by proximity to alternative fuel fleets; adopted in the California Enery Commission's M85 network. 3. Massive infrastructure development effort, coupled with the financial depth to persist until fuel throughput reaches economically sustainable levels. This approach may be unstable if tied solely to the fortunes of a single company. 4. “Strategic concentration,” the development of a dense fueling network in delimited areas, allowing the incremental deployment of dedicated fuel vehicles.

The importance of the automotive test facility has increased significantly due in large part to continuous pressure on manufactures to shorten product development cycles. Test facilities are no longer used only for regulatory testing, or development testing in which the effects of small design changes (A-to-B testing) are determined; automotive manufacturers are beginning to use these facilities for final design validation, which has traditionally required on road testing. A host of resources have gone into the design and construction of facilities with the capability to simulate nearly any environment of practical importance to the automotive industry. As a result, there are now a number of test facilities, and specifically wind tunnels, in which engineers can test most aspects of a vehicle's performance in real-world environments.

This paper discusses the change in vehicle parameters when moving from a conventional internal combustion engine (ICE) to an electric motor. In particular, the paper discusses the impact on the wheel end bearings, which must handle higher GAWRs (gross axle weight ratings) at lower center of gravity heights on electric vehicles. These changes require bearings to handle higher loads. Typically, larger loads increase the bearing size and with it, the mounting interface dimensions for auxiliary components. In this paper, The Timken Company demonstrates an alternative bearing design that can handle higher electric vehicle GAWRs but allows for continuity in the surrounding brake corner components - potentially saving OEMs significant design costs and delays. This solution focuses on the mid- and large-size SUV market where bearing capacity could be a limiting factor for electric vehicle variants - driving significant wheel end brake corner design changes to accommodate the larger bearings.

The design of integrated modular avionics (IMA) for next-generation aircraft is a significant challenge for the industry in terms of complexity, time-to-market, certification and design effort. Because of those constraints, traditional hand-coding may no longer be a cost-effective option, especially for DO-178C Design Assurance Level (DAL) A Safety-critical applications. While the use of Commercial Off-The-Shelf (COTS) HMI-modeling tools could be a more efficient option, its introduction in an existing environment may result in high risk and effort. This paper presents the approach for the evaluation of the SCADE Display tool for a primary flight display (PFD) application. In this evaluation, a subset of a previously developed PFD was re-modeled with SCADE Display. The creation of the model served as an evaluation of the usability and the flexibility of the tool. The integration of the generated code on an existing platform was evaluated.

The aim of this paper is to present and discuss a case study on how an Original Equipment Manufacturer's technical design center translates and integrates legislative environmental requirements into their product range. The integration of these environmental requirements during the conceptual design phase, where the significant proportion of resources is committed, is of utmost importance. Additionally, with increasing levels of product development being conducted by the first-tier suppliers, there is greater emphasis on the Original Equipment Manufacturer, who controls the product specifications, for translating and filtering the environmental requirements down the supply chain. A Requirements Management based model addressing environmental issues is described.

When preparing inventory models, it is desirable to obtain representative distance-specific emissions factors that truthfully represent the vehicle activity on a particular road (facility) type. Unfortunately, emissions values are often measured using only one test schedule, which represents a single average speed and a specific type of activity. This paper investigated the accuracy of predicting the emissions for a test schedule based on measurements from a different test schedule for the case of a medium heavy-duty truck. First, the traditional Speed Correction Factor (SCF) approach was examined, followed by the use of a power-based model derived from continuous data, followed by an artificial neural network (ANN) approach. The SCF modeling used distance-averaged emissions and cycle-averaged vehicle speed to predict distance-averaged NOx. The power-based modeling was based on linear and polynomial correlations between continuous axle power and NOx.

Any broadly surfaced impact imparts to the head a force by which it is accelerated. If the impact is directed at the center of mass of a freely movable object, the resulting motion is a translation acceleration. If the impact is directed eccentrically, the result is a combined translational and rotational acceleration. The magnitude of the rotational acceleration is related to the degree of eccentricity of the acting force. The magnitude of the translational acceleration is related to the distance between the point of fixation and the center of gravity of the head. The distinction between the two types of acceleration is important in view of the different physical processes they initiate in the brain. Pure translational acceleration creates pressure gradients, while pure rotational acceleration produces rotation of the skull relative to the brain. Both processes are the effects of mass inertia of the brain.

The motion of occupants under the conditions of traffic accidents can be described in more or less extensive simulation models. For the evaluation of loadings on occupants, it is indispensable to include all exterior forces (e.g. seat forces) which have influence on motion behaviour, as well as contact models which describe contact forces during impact (e.g. against the steering wheel). In component tests, seat belt material, steering wheel and seat were examined; force/deflection characteristics were derived from these experimental results. Utilization of these dynamic charateristics in simulation models results in a realistic description of the motion of the occupant. In this way, mechanical loads on the occupant can also be evaluated, this enabling the assessment of risk of injury.

A methodology is presented for developing two tools for design guidance of joints in car bodies. The first tool rapidly predicts the performance characteristics of a given joint. The second finds a joint design that meets given performance targets and satisfies packaging and manufacturing constraints. These tools translate the design parameters defining the geometry of a joint into performance characteristics of that joint and vice-versa. The methodology is demonstrated on a joint of an actual car.

E-spring is an optimized trend of springs for vehicle suspension systems. Experimental and transmissibility analyses of laminated fibrous composite E-springs are conducted. The mechanical and frequency-response-based properties of these springs are investigated experimentally at both of the structural and constitutional levels. Thermoplastic-based and thermoset-based fibrous composite structures of the E-springs are modified at micro-scale with various additives and consequently they are compared. The experimental results reveal that additives of micrometer-sized particles of E-glass fibers as well as mineral clay to an ISO-phthalic polyester resin of the composite E-spring can demonstrate superior characteristics. The transmissibility analysis of laminated fibrous composite E-springs reveals superior frequency ratio.

Automatic transmission fluids can oxidize with use, causing marginal transmission performance and eventual transmission malfunction. Periodic fluid changes are presently recommended to alleviate this problem. Fluid oxidation is promoted in current transmissions because they breathe air freely through a vent tube. To reduce fluid oxidation, and thereby improve fluid and transmission durability, a one-way check valve, called the Transmission Air Breathing Suppressor (TABS), was designed to restrict the intake of air into the transmission and to replace the conventional vent tube. The effectiveness of the TABS valve in reducing fluid oxidation was determined in high temperature transmission cycling tests and in taxicab tests. Fluid oxidation results with the TABS valve-equipped transmissions were compared to those with normally-vented transmissions. By reducing the amount of oxygen in the transmission gas, the TABS valve nearly eliminated fluid oxidation.

The American motorist's demand for optimum vehicle performance and reliability has brought about increased emphasis on automatic transmission cooling systems, to meet higher power to weight ratios as well as increased operating range requirements. To provide a reliable, economical cooling system, engineers have incorporated air cooling on many automatic transmissions. When integral with the torque converter, air cooling is direct in action and independent of the engine cooling system. This paper reviews the evolution of air cooling, examines transmission cooling objectives, and discusses the considerations involved in design. The qualification tests for proper evaluation of a cooling system are reviewed.

Due to the multitude of external design constraints, such as increasing fuel economy standards, and the increasing number of global vehicle programs, developers of automotive transmission controls have had to cope with increasing levels of system complexity while at the same time being forced by the marketplace to improve system quality, reduce development costs, and improve time to market. General Motors Powertrain (GMPT) chose to meet these challenges through General Motors Company's Road-to-Lab-to-Math (RLM) strategy, particularly the Math-based method of a virtual vehicle simulation environment called System Simulation. The use of System Simulation to develop transmission control algorithms has enabled GMPT to improve product quality and reduce development times and costs associated with the dependence on physical prototypes. Additionally, System Simulation has facilitated the reuse of GMPT controls development assets, improving overall controls development efficiency.

Concerning the automotive transmission, the power loss reduction can be achieved by substituting the tapered roller bearings and reducing operating temperature. With SKF's low friction tapered roller bearings, it is possible to reduce frictional torque by 30% on a manual transmission (MT) with lower fuel consumption and lower operating temperature. Lower fuel consumption and CO₂ emission are both special drivers for transmission's future generation powertrains. This paper presents the results obtained for a MT with the SKF's E2 bearings as a proposal for the current differential bearings.

Breather assembly is mounted on transmission to maintain the pressure equilibrium inside transmission. Breather allows the transmission to breathe air when the air inside transmission expands or contracts due to heating and cooling of lubricating oil during vehicle running. Breather allows the hot air to escape and cool air to enter into the transmission to prevent overheating issue. Failure of breather assembly can lead to pressure buildup inside transmission and further leading to leakage from transmission oil seals. Oil leakage through the breather assembly is governed by parameters such as opening pressure, location and orientation of breather etc. The transmission undergoes different operating conditions of input speed, load, temperature, inclination etc. Also, breather assembly is designed and positioned in such a way that there is no leakage through breather due to oil splash inside the transmission.

For several years flat cables for the use in the automotive wiring harnesses have been attracting attention. Less weight, less space and higher automation degree are the key factors, which promise a benefit from the introduction of the new technology. The well defined electromagnetic properties are also often mentioned as an advantage of flat cables, because of the precise and constant routing in the car. Although it is true, that statistical error due to an unfavorable position of the cables in the harness is reduced, on the other hand the systematical error due to it's geometry is strongly enhanced. Since basic parameters like impedance or crosstalk characteristics are not specified for the cable types for CAN-transmission used in automotive, it is difficult to qualify a selected wiring system in the early development phase of a car model.

Transmission fault monitors must take into account failures from both hardware and software. Hardware failures, which, result due to a complete loss of function or through wear over time, are a predictable and expected failure source. Software faults, however, are unpredictable, since the fault is always present, and simply needs the right set of circumstances to occur. In automatic transmission systems, where there are no hydraulic or mechanical interfaces to prevent improper engagement of the various friction elements, the need for reliable and predictable software becomes paramount to avoid conditions where the transmission fails to transmit torque to the driving axles. In addition, the monitor must take the necessary measures to avoid false positive detection of an impending transmission tie-up.