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The large wind tunnel at the Technische Universität München was upgraded by integrating a modular single-belt system, which enables the simulation of moving ground conditions for ground vehicle testing. Central part of this system is its large belt that moves at a maximum speed of 50 m/s. This belt not only simulates the relative motion between the model vehicle under investigation and the floor, but also drives the model's wheels. Due to its size, the wind tunnel facility is suited for testing 40%-scaled models of typical passenger cars, which are held in place by a newly designed model support system consisting of five struts: One strut to support the body of the model and four struts to hold the model's wheels on top of the moving belt. Another crucial step in upgrading the wind tunnel was to install a boundary layer scoop system to reduce the thickness of the boundary layer approaching the moving belt.

Over the past 25 years Space Solar Dynamic component development has advanced to the point where it is considered a leading candidate power source technology for the evolutionary phases of the Space Station Freedom (SSF) program. Selection of SD power was based on studies and analyses which indicated significant savings in life cycle costs, launch mass and EVA requirements were possible when the system is compared to more conventional photovoltaic/battery power systems. However, like any new or untested system proposed for space applications a number of issues have been raised concerning performance of the components when integrated into a system in a vacuum environment. Issues associated with micro-gravity operation such as the behavior of the thermal energy storage materials are being addressed in other programs. A ground test of a 2 kWe solar dynamic system is being planned by the NASA Office of Aeronautics and Space Technology to address the integration issues.

Western Washington University has built two ground-up hybrid electric vehicles. The first vehicle, Viking 21, was utilized to test various systems before incorporating them into Viking 23 which is the vehicle discussed in this paper. The front wheels are driven by two brushless D.C. motors through a purpose built 4 speed transaxle incorporating a limited slip differential. The rear wheels are driven with a natural gas, fuel injected, four cylinder, 16 valve engine through a six speed gearbox and mechanical diodes at the rear wheel hubs. The body-chassis is made from sandwich construction carbon fiber composite. The NiCd battery is charged from a 720 Watt solar array covering the entire surface of the upper body's aerodynamic shell. The low weight (900 Kg), combined with a Cd of .275, yield a gasoline equivalent efficiency of more than 200 miles per gallon.

There exists a growing trend within our industry to move in the direction of a mass market air transport system with emphasis on greater efficiency of equipment, capital, and energy. While satisfying the essential needs of the market majority the mass market approach compromises the needs of the more service oriented market. Such compromises are changing the perception of the industry from service conscious to price conscious. It need not be either price or service - it can be both. Within resource limitations further specialization can produce satisfaction in both the lower fare mass market and the higher fare service market. In addition specialization carries with it the benefit for further product differentiation thus improving potential profitability in a highly competitive industry.

Used lube oil and transmission sump filters are not considered hazardous waste if they are disposed of according to Federal guidelines. The options for disposal after hot draining include incineration, landfilling, and recycling. Landfilling of filters increasingly have been banned by more and more states. The states are requiring that filters be recycled. The OEMs have acknowledged this governmental trend for life cycle recycling by their establishment of the Vehicle Recycling Partnership, one of the consortia of the United States Council on Automotive Research (USCAR). An all plastic transmission sump filter has been designed, developed, and is currently being manufactured for certain GM and Ford platforms. The use of a composite resin material and proprietary technology facilitates the effort to recycle. The recycled material may be used again when combined with virgin material to meet the OEM material specifications. Residual oil may also be recovered and reprocessed.

The stamping of thermoplastic sheet is gaining acceptance in the automobile industry. The process has been used in consumer product areas which are less demanding than automotive, but this has demonstrated process viability. As the process gains in acceptance, special materials are being developed for stamping of components which have properties required for specific applications. There are several variations of the basic process as related to the product, material, and equipment. The definite advantage of stamping is rapid cycle time. In-the-mold decorating and pre-decorated materials will provide further applications in trim components. Stamping of thermoplastic provides an additional tool for automotive engineers.

The term “Guided-light” applies to a new concept of internal light utilization applicable primarily to opaque-faced, “edge-lighted,” plastic panels. Manufacturing techniques based on this concept make possible the production of “one-piece” illuminable cockpit and control console panels that have unprecedented efficiency and “light-throw” yet retain the dimensions and conventional appearance of the “single panel” types. It is estimated that Guided-Light panels require less than 25% of the number of embedded lamps that are now used in state-of-the-art, embedded lamp, single panels. Some of the techniques of “guided-light” light distribution are related to those that have been developed for the Duo-Panel but others are unique. This paper lays the ground work for early industrial application to aero-space indicating instruments. Optical efficacy of candidate combinations of materials may be determined through use of the curves presented.

The Guideway Bus (GB) system is a kind of guideway transit system using conventional buses fitted with mechanical guidance equipment. This paper presents a general overview of the GB at the Asian-Pacific Exposition: FUKUOKA '89. This is the first commercial application under license of the Japanese authorities. This system consists of 4 vehicles, 4 stations, a 900 m long double-track guideway with only a single-track section between intermediate stations, a control center, and a maintenance yard. It is capable of carrying 975 pass./h/direction at the minimum headway of 4 minutes. The vehicles are diesel-engine buses, on which the driver operates both brake and accelerator, but does not steer the wheel except for driving in the yard. A vehicle protection subsystem has been developed for avoiding collision or deadlock on the single-track.

AN investigation of the accelerated oxidation method for predicting the gum stability of gasolines was made to determine the effects of oxygen pressure and of temperature on the observed induction periods. The data obtained on the effect of pressure indicated that there was a definite relation between the induction period at any pressure and the induction period at an air pressure of 1 atmosphere. The data obtained on the effect of temperature showed that the induction periods of different gasolines changed to a different extent with temperature, so that gasolines with the same induction period at any one temperature might have very different periods of stability at storage temperatures. Since temperature has a marked effect on the observed induction period and since the gasoline is at a lower temperature than that of the bath for a considerable period of time at the beginning of the experiment, a correction factor was applied to obtain true induction periods at the bath temperature.

The Homogeneous Charge Compression Ignition (HCCI) combustion progress has been characterized by means of high-speed fuel tracer Planar Laser Induced Fluorescence (PLIF) combined with simultaneous chemiluminescence imaging. Imaging has been conducted using a high-speed laser and detector system. The system can acquire a sequence of eight images within less than one crank angle. The engine was run at 1200 rpm on iso-octane or ethanol and a slight amount of acetone was added as a fuel tracer, providing a marker for the unburned areas. The PLIF sequences showed that, during the first stage of combustion, a well distributed decay of fuel concentration occurs. During the later parts of the combustion process the fuel concentration images present much more structure, with distinct edges between islands of unburned fuel and products.

The introduction of MultiAir technology [8] has had a strong impact on engine performance, fuel consumption, emissions and control. This technology, intended at first for gasoline engines and applied only on intake valves, is aiming at the reduction of engine breathing losses and, as a consequence, reduction of pollutant emissions and fuel consumption, together with an improvement of maximum intake efficiency. Further positive effects of MultiAir technology have been a significant improvement of Low End Torque, engine driveability (“fun-to-drive” index) and other operating conditions (e.g. idle control). Current development of MultiAir technology is focusing on a better management of hot EGR (Exhaust Gas Recirculation), still acting only on the intake side, although with specifically designed valve lift profiles. This application of MultiAir technology is pushing gasoline engines towards new levels of performance improvements.

For several years the NASA Langley Research Center has conducted in-depth research in supporting technology advancement for a concept which could complement the Space Shuttle operation and ensure the ability to transport people to and from earth orbit. The concept is called the HL-20 Lifting-Body and it has been defined as an option for future development as a Personnel Launch System (PLS). This paper will describe early lifting-body research, expected PLS mission requirements, the HL-20 concept design status, and those features which enhance aerodynamic and aerothermodynamic performance, operation efficiency, maintainability, reliability, and crew safety. The HL-20 concept evolved from early lifting-body research in the 60's and 70's and has been designed for the primary mission of changing the Space Station Freedom crew. It is sized to accommodate eight passengers plus a flight crew of two. The duration of the mission is 3 days.

There is a great deal of interest in new technologies to assist in reducing the CO2 output of passenger vehicles, as part of the drive to meet the limits agreed by the EU and the European Automobile Manufacturer's Association ACEA, itself a result of the Kyoto Protocol. For the internal combustion engine, the most promising of these include gasoline direct injection, downsizing and fully variable valve trains. While new types of spray-guided gasoline direct injection (GDI) combustion systems are finally set to yield the level of fuel consumption improvement which was originally promised for the so-called ‘first generation’ wall- and air-guided types of GDI, injectors for spray-guided combustion systems are not yet in production to help justify the added complication and cost of the NOx trap necessary with a stratified combustion concept.

This paper discusses the philosophy that guided the design of a 400 hp steering transmission used in the Marine Corps' new 50,000 lb amphibious personnel carrier. It describes in detail the design of the steer and brake section and the problems posed by utilizing an advanced design hydrostatic steer unit. It covers the design of the gearing, the housing, and the hydraulic control and lube system, and it gives information gathered during nearly a year of testing.

The historical status of the Head Up Display (HUD) as Primary Flight Instrument in both military and civil applications is reviewed. The rôle of the HUD in air carrier applications as a landing aid is considered in detail. An architecture is presented for a HUD suitable for CAT IIIB and CAT IIIC approaches, and for integration into the wider avionics system to provide full-time primary flight instrument benefits.

Head-up displays in modern fighter aircraft evolved from rustic gun sights into the complex flight information and weapons delivery presentation of today. During this evolution, symbology, display parameters, terminology and flight procedures and techniques changed significantly. Unfortunately this resulted in a proliferation of terms, symbols and methods of describing the various applications. Pilots today are using these new displays, the functions of which are often not intuitively obvious and which are described by literature that is sometimes confusing or incomplete. As a result, pilot opinions on the HUD and its use for aircraft control and navigation range from “I never use it” to “I wouldn't fly in weather without it.” If the HUD is to become a viable means of providing information in a full mission context, a reasonable standardization of terms is needed to identify and describe its various features and their use.

The potential of digital human modeling to improve the design of products and workspaces has been limited by the time-consuming manual manipulation of figures that is required to perform simulations. Moreover, the inaccuracies in posture and motion that result from manual procedures compromise the fidelity of the resulting analyses. This paper presents a new approach to the control of human figure models and the analysis of simulated tasks. The new methods are embodied in an algorithmic framework developed in the Human Motion Simulation (HUMOSIM) laboratory at the University of Michigan. The framework consists of an interconnected, hierarchical set of posture and motion modules that control aspects of human behavior, such as gaze or upper-extremity motion. Analysis modules, addressing issues such as shoulder stress and balance, are integrated into the framework.

The ESA HUYGENS probe is scheduled for launch as part of the CASSINI mission to the Saturnian system in 1997, due to arrive at TITAN in late 2004. The HUYGENS probe shall then perform a 2.5 h exploratory descent in TITAN's atmosphere. This descent phase will be preceded by a 3 mn Entry phase during which the velocity of the European probe will be reduced from 6 km/s down to around 400 m/s. This will be obtained by means of a 2.7 m diameter shield. This paper presents the general rationale used for the shield design, development and qualification.The following steps are described: choice of shield concept and materials verification of compliance of thermal protection materials with shield requirements development of new processes imposed by the mission specificities verification of interface compatibility between thermal protection materials and shield structure qualification of the thermal protection system and of the shield design to the entry mechanical loads and thermal fluxes.

The objective of the European Hydro-Gen project is to develop an innovative PEM Fuel Cell (PEMFC) energy system, based on high pressure gaseous hydrogen tanks. The developed system would result in a large increase in performance compared to the state of the art in terms of components, PEMFC stack and energy system, with an emphasis placed on cost reduction for on board applications in fuel cell electric vehicles. This is achieved by developing a low temperature (80°C) and low pressure (1.5 Bar abs) 30 kW PEMFC stack based on innovative core components, 700 bars H2 tanks with optimized weight and volume, and integrating the fuel cell drive train in a compact electric van Peugeot Partner Electric. The vehicle has a driving range of 300 km for a 350 bar fill-up, and overall performances comparable to those of the Partner Electric version. The efficiency of the FC stack alone is 56% at 1.5 bar abs. The energy consumption of the vehicle is around 1.2 MJ/km that is 1 kg of H2 per 100 km.

Aircraft have been equipped with Auxiliary Power Units (APUs) to provide compressed air and shaft power. The Hamilton Standard APU for the Lockheed TriStar airplane represents a new and different design concept that will result in major improvements in operating economy and reliability to the airline operators. Design and development stages of the APU are presented in this paper. The free-turbine engine design offers excellent full- or part-time economy and efficiency while operating at high engine-cycle pressure ratios. This APU also offers the concept of automatic paralleling of electrical equipment.