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Operator/crew comfort inside a combat vehicle has not had the attention and priority it truly deserves. Inside combat vehicles accommodation is often cramped and surfaces are hard and unfriendly that could easily cause injury to the occupant. Adding excessive heat to this scenario only increases the chance for failure to perform, injury or possible loss of life. The field manual 90-30, Desert Operations, states, “highest known ambient temperature recorded in a desert was 136deg F, lower temperatures than this produced internal tank temperatures approaching 160 deg F in the Sahara Desert during the Second World War”. It is a fact that a weapon is only as good as its operator. An alert operator at his or her peak efficiency tends to perform better. The effect of heat on a combat vehicle crew can be considered a continuum ranging from discomfort to heat casualty (exhaustion and heat stroke).

This paper reports on the utilization and problems encountered using a gas turbine engine as the power source for an aircraft mounted auxiliary power system. The information presented is based on a year’s operation of the Boeing 727 by two major airlines, American and United.

Driver Assistance Systems (DAS) like e.g. distance control systems are more and more evolving in a variety of cars, and the goal is mainly to support the driver in his driving task in order to improve convenience. The strategic approach to DAS at BMW is outlined and resulting system functions are explained. The paper shows the specific design and implementation of systems that interact with the vehicle dynamics on the same level as the driver. Special emphasis is given to their interaction with the driver. Therefore the Human Machine Interaction is one of the focus points within the development process. BMW ensures the mode awareness of the driver by presenting the relevant information in optimized displays within the vehicle.

A comparison is being undertaken of the performance of five identical vehicles, using alternative fuels, by the Public Works Department of Victoria. The comparison is being made in normal vehicle duty in service, over 60,000 km, and by laboratory testing. Problems encountered in vehicle conversion to alternative fuels, and in installing instrumentation, and in normal operation are described. Laboratory test results of vehicle efficiency and emissions are presented and compared. The fuels considered are petrol, diesel fuel, Liquified Petroleum Gas (LPG), and Compressed Natural Gas (CNG). An Electric powered vehicle is proposed for this trial and is described. Initial conclusions indicate favourable cost reduction in using LPG or diesel fuel compared with Petrol and CNG.

There are many steps involved in preparing a payload for a mission into space on the Space Shuttle. Operations at the John F. Kennedy Space Center (KSC) are the last of those steps for the hardware before the payload is launched. To demonstrate those operations that deal with Life Science Payloads, this paper will discuss KSC processing of the Space Transportation System (STS) -58 Spacelab Life Sciences-2 (SLS-2) mission which was launched on the Space Shuttle Columbia, October 18, 1993 and landed at Edward's Air Force Base (EAFB) on November 1, 1993.

An air suspension has been developed to meet the needs of the Class 8 truck market of the 1980's. This design was developed to satisfy a list of objectives that conform to present and future requirements for a tandem axle rear suspension. Throughout the development program, exhaustive tests were conducted to assure successful performance and minimize the possibility of last minute tooling changes. Dual anti-sway bars contribute significantly to the dynamic performance characteristics of this suspension and, along with the full air springing, represent its most significant performance features.

In order for the supersonic transport to be economically feasible, the cost of the fuel should be essentially equivalent to ASTM type A and type A-1 prices. A survey was conducted to determine the properties of commercial kerosene. Physical and chemical properties of commercial kerosene are presented with special emphasis on thermal stability characteristics. The results of the survey indicated that some of the commercial aviation kerosene fuel being supplied to the commercial subsonic jets of today may be satisfactory for use in the supersonic transport.

A semi-technical history of automotive headlighting in the United States written as an audio-visual presentation. Not fully illustrated.

Kettering University's entry in the 2003 Clean Snowmobile Challenge entails the installation of a fuel injected four-stroke engine into a conventional snowmobile chassis. Exhaust emissions are minimized through the use of a catalytic converter and an electronically controlled closed-loop fuel injection system, which also maximizes fuel economy. Noise emissions are minimized by the use of a specifically designed engine silencing system and several chassis treatments. Emissions tests run during the SAE collegiate design event revealed that a snowmobile designed by Kettering University produces lower unburned hydrocarbon (1.5 to 7 times less), carbon monoxide (1.5 to 7 times less), and oxides of nitrogen (and 5 to 23 times less) levels than the average automobile driven in Yellowstone National Park. The Kettering University entry also boasted acceleration performance better than the late-model 500 cc two-stroke snowmobile used as a control snowmobile in the Clean Snowmobile testing.

Kettering University's entry in the 2002 Clean Snowmobile Challenge involves the installation of a fuel injected four-stroke engine into a conventional snowmobile chassis. Exhaust emissions are minimized through the use of a catalytic converter and an electronically controlled closed-loop fuel injection system, which also maximizes fuel economy. Noise emissions are minimized by the use of a specifically designed engine silencing system and several chassis treatments. Emissions tests run during the SAE collegiate design event revealed that a snowmobile designed by Kettering University produces lower unburned hydrocarbon (1.5 to 7 times less), carbon monoxide (1.5 to 7 times less), and oxides of nitrogen (and 5 to 23 times less) levels than the average automobile driven in Yellowstone National Park. The Kettering University entry also boasted acceleration performance better than the late-model 500 cc two-stroke snowmobile used as a control snowmobile in the Clean Snowmobile testing.

Electronics components are estimated to be between 9 to 15 % of a total vehicle cost, and this trend will remain strong for the next years. The amount of electronics content in a vehicle has grown steadily since 1970's, and as a result, development challenges such as testing and validation are a key aspect of its overall development costs. Testing costs can amount easily to US$ 500 k in medium complex automotive parts of a vehicle (e.g. instrument cluster) depending on a specific OEM customer demand, and this on top of limited regional laboratory capacity can also lead to increased testing time. The goal of this paper is to outline key aspects of electronics in vehicle components testing, including overall costs and timing, and propose a lean approach to optimize such costs & timing. The key aspects of such optimization include not only resources, but also laboratories and upfront OEM customer planning.

Traditional methods for optimizing an Electrical Distribution System have always been less than ideal. Engineers are typically left with unsophisticated and manual spreadsheet tools. Any detailed feedback on critical metrics such as cost or weight typically relies on another organization and requires week or months. The resulting EDS is inevitably suboptimized, not due to a lack of engineering ability, but rather the tools available. To ensure that the EDS design is optimized from the outset, the design environment itself must be enhanced. There are four key attributes to this design environment. Automation is required to ensure that designs are synthesized rather than manually created. There are many benefits of this, but efficiency and repeatability are most important to this conversation. The ability to measure and assess the design must be available in the design, while the engineer is designing. The metrics used to measure must be easy to create and modify.

We study the NOx storage process in lean NOx traps using bench-flow experiments and simulated diesel exhaust. Given that formulation alone is an inadequate indicator of performance (due to the effects of manufacturing processes) a minimal set of experiments is always needed to compare the performance of LNTs. We define simple performance measures based on such a set of experiments that can be used to compare lean phase operations of various LNTs under various conditions concisely. Though the noble metal sites are essential for storage, the benefits of increasing noble metal loading start to wane beyond a certain limit. Our experiments suggest a possibility that a lean NOx reduction reaction may be occuring in LNTs. If this reaction is confirmed further in future experiments, its products need to be identified. The sorbent shifts the equilibrium between NO and NO2 towards NO.

This paper outlines field performance shortcomings historically observed in automotive instrument panels (I/Ps) and discusses the role materials play in these deficiencies. Additionally, specific material development requirements for a ten year instrument panel are discussed. While design and the placement of adjacent vehicle components, such as windshield glass, play key roles in affecting the durability of an I/P, functional and cosmetic performance in large part depend on the materials chosen for construction. Tradeoffs in short term performance (processability during manufacture) and long term performance (field weatherability) often exist for the chemical constituents comprising instrument panel assemblies. In order to obtain an optimal combination of properties, specific performance criteria must be identified and prioritized.

Disk type brakes and clutches are important components of many automotive and off-highway drivetrains. Wet brakes and clutches are becoming widely used for heavy duty applications where durability is important. Traditionally, brakes and clutches are designed to provide adequate torque capacity using simple and well known techniques, but other variables need to be considered. While the design analysis of brakes and clutches for energy capacity and chatter can be extremely complex, for most applications there are some relatively simple relationships that can be applied to obtain an adequate design.

Model-based development and autocoding have become common practice in the automotive industry over the past few years. The industry is using these methods to tackle a situation in which complexity is constantly growing and development times are constantly decreasing, while the safety requirements for the software stay the same or even increase. The debate is no longer whether these methods are useful, but rather on the conditions for achieving optimum results with them. From the experiences made during the last decade this paper shows some of the key factors helping to achieve success when introducing or extending the deployment of automatic code generation in a model-based design process.

A successful short-haul transport must satisfy customer and marketplace requirements and be attractive economically. This paper examines the marketplace in the late 1970 time period to determine the payload-range and other performance requirements for a wide-bodied twin-jet transport. Environmental and operating cost targets are established, and the size of the market is estimated. An “optimal” design is then described which essentially represents the best possible airplane using the technology available in the time period best suited to the customer and marketplace requirements. Design data are presented that show the sensitivities of the design to some of the primary configuration variables. Certain design compromises are considered that have to do with airframe commonality with the manufacturer's other transports.

The increasingly stringent requirements in relation to safety, fuel economy, emission reduction, and onboard diagnostics are pushing the automotive industry toward more innovative solutions and a rapid increase in microcontroller performance. This paper will list the key factors necessary to increase overall data throughput and provide the right features to satisfy the coming drivetrain requirements. The paper will address different aspects such as: microcontroller architecture, cores, memories, silicon technologies, assembly / packaging, and development tools. It will also present techniques to improve modularity, scalability and configurability that will offer a migration path to permit the evolution and even revolution of drivetrain electronics. Since quality and reliability requirements are among the most stringent of any application fields, the paper will outline the path to reach zero-defect products.

This paper highlights the installation requirements for textured spray control flaps fitted to heavy duty trucks. Tractor-trailer combinations operating on wet roads at highway speeds generate visibility impairing spray clouds. A key source of this fine droplet spray formation occurs when high velocity water thrown from truck tires impacts hard surfaces such as fuel tanks or conventional smooth surface flaps. Textured flaps absorb the tread throw impact returning the water to the road surface in large droplets. This paper addresses the placement of the flaps for optimizing spray control efficiency. Special focus is placed on the practical flap fitment behind the tractor steered and drive axles and the rear trailer axle. Moreover, the need for stronger flap support systems is addressed to accommodate the greater snow accumulations characteristic with textured spray control truck flaps.