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An overview of Space Station Freedom Thermal Control System (TCS) and Environmental Control and Life Support System (ECLSS) integration is presented for Stages 2-6. Particular attention is given to issues associated with integrating five distinct, functioning spacecraft with hardware not specifically designed for intermediate stages. Areas specifically addressed include integrated ECLSS temperature and humidity control performance, thermal load balancing, performance and verification requirements, interface verification procedures, TCS activation sequence, resource allocation and Space Shuttle integration.

Time Triggered CAN (TTCAN) is an extension of the well-known CAN protocol, introducing to CAN networks time triggered communication and a system wide global network time with high precision. Time Triggered CAN has been accepted as international standard ISOCD11898-4. The time triggered communication is built upon the unchanged standard CAN protocol. This allows a software implementation of the time triggered function of TTCAN, based on existing CAN ICs. The high precision global time however requires a hardware implementation. A hardware implementation also offers additional functions like time mark interrupts, a stopwatch, and a synchronization to external events, all independent of software latency times. The TTCAN testchip (TTCAN_TC) is a standalone TTCAN controller and has been produced as a solution to the hen/egg problem of hardware availability versus tool support and research.

Today, the DPF and SCR catalysts are combined sequentially in diesel exhaust systems. However, such sequential system configuration has several drawbacks: 1) large volume; 2) insufficient temperature for the SCR catalyst during cold start when DPF is placed in front of SCR; and 3) unfavorable conditions for passive soot regeneration if SCR is placed upstream of the DPF. The problems can potentially be solved by integrating the SCR catalyst into the particulate filter as one multifunctional unit. The study indicates that SCRonDPF based on Cu-zeolite type as SCR material can achieve the NOx conversion levels close to flow-through SCR catalysts for LDV (Light Duty Vehicles) using forced regenerations. Forced soot regeneration solves potential sulfur poisoning.

The evolution of computer technology has made CAE ( Computer Aided Engineering ) an integral part of the total vehicle development process. Particularly for crash development, up-front input is crucial in determining vehicle architecture, performing trade off studies and setting design targets. Detailed FEA ( Finite Element Analysis ), although more accurate, is not always suitable at this stage due to (1) the lack of Detailed design information and (2) the large amount of modelling and analysis efforts. Concept/Hybrid models, however, can provide important input to make early design decisions without a detailed design. This paper uses a concept model to illustrate the above mentioned point. The model contains, the interior structure of a pick-up truck, driver occupant, restraints, and a detailed steering column assembly. Correlation with a physical test demonstrates the reliability of the model. Several restraint parameters which influence occupant performance are identified.

A simulation approach is defined that integrates a military mission assessment tool (One Semi-Automated Forces) with a commercial automotive control/energy consumption development tool (Autonomie). The objective is to enable vehicle energy utilization and fuel consumption impact assessments relative to US Army mission effectiveness and commercial drive cycles. The approach to this integration will be described, along with its potential to meet its objectives.

The objective of this paper is to demonstrate the use of computer modeling and simulation as an effective analytical tool which can be integrated with representative data from user duty cycles and validated against response data measured on a vehicle. Computer modeling is an increasingly important design tool, but the necessity of real-world test data is often overlooked. This paper will present an example of the process, using the Logistics Vehicle System Replacement (LVSR). The project uses real-world proving ground data as inputs to the vehicle model, as well as instrumented vehicle test data to validate outputs of the vehicle model.

Two widely available engine and hybrid electric vehicle (HEV) simulation packages have been integrated to reduce fuel consumption and pollutant emissions for a hybrid electric sport utility vehicle. WAVE, a one-dimensional engine analysis tool available from Ricardo Software, was used to model a 2.5L 103 kW Detroit Diesel engine. This model was validated against engine performance and emissions data obtained from testing in a combustion laboratory. ADVISOR, an HEV simulation software developed by the National Renewable Energy Laboratory in partnership with the Department of Energy (DOE), was used to model a 2002 Ford Explorer that is being converted into an HEV by the Penn State University FutureTruck team. By integrating the output file from WAVE as the input engine data file for ADVISOR, one can predict the effect of changes in engine parameters on vehicle emissions, fuel consumption, and power requirements for specified drive cycles.

In this paper we show the benefits of integrating a sophisticated engine model into an engine software development process. The core goal is the simulation based tuning of engine control parameters. The work reported here is resulting out of a prolonged cooperation between Siemens VDO Automotive AG and the Institute of Industrial Information Technology, University of Karlsruhe (TH), Germany. The approach is based on a model of the variable energy conversion process within a Diesel engine. The model features phenomenological fuel spray and vaporization models as well as cylinder individual mechanical aspects and fully copes with multiple injection systems. To be useful for an industrial function development process it provides a flexible and modular structure and features computational efficiency - considering real-time capability. The model is matched with the behavior of an engine of interest and connected with a control function under development.

A continuous multi-component fuel evaporation model has been integrated with an improved G-equation combustion and detailed chemical kinetics model. The integrated code has been successfully used to simulate a gasoline direct injection engine. In the multi-component fuel model, the theory of continuous thermodynamics is used to model the properties and composition of multi-component fuels such as gasoline. In the improved G-equation combustion model a flamelet approach based on the G-equation is used that considers multi-component fuel effects. To precisely calculate the local and instantaneous residual which has a great effect on the laminar flame speed, a “transport equation residual” model is used. A Damkohler number criterion is used to determine the combustion mode in flame containing cells.

The heat release of the low temperature reactions (LTR or cool-flame) under Homogeneous Charge Compression Ignition (HCCI) combustion has been quantified for five candidate fuels in an optically accessible Rapid Compression Expansion Machine (RCEM). Two technical fuels (Naphthas) and three primary reference fuels (PRF), (n-heptane, PRF25 and PRF50) were examined. The Cetane Numbers (CN) of the fuels range from 35 to 56. Variation of the operating parameters has been performed, in regard to initial charge temperature of 383, 408, and 433K, exhaust gas recirculation (EGR) rate of 0%, 25%, and 50%, and equivalence ratio of 0.29, 0.38, 0.4, 0.53, 0.57, and 0.8. Pressure indication measurements, OH-chemiluminescence imaging, and passive spectroscopy were simultaneously implemented. In our previous work, an empirical, three-stage, Arrhenius-type ignition delay model, parameterized on shock tube data, was found to be applicable also in a transient, engine-relevant environment.

This paper presents preliminary results of a study aimed at specification, selection and preliminary design of subsystems required to transform maneuvering, reentry body technology into a piloted, high performance Spaceplane, potentially capable of operating throughout cislunar space. This study, under contract to the U.S. Air Force, is being conducted by SRI-International, Hamilton Standard and several other aerospace contractors. Potential Spaceplane applications include placement, support, servicing and retrieval of satellites, and a variety of other military missions. The emphasis in this paper is on key issues relating to integration of the crewman into the vehicle. Issues discussed include environmental control/life support, cabin and spacesuit pressure levels and methods of heat rejection. Human factors issues relating to displays and controls, and prevention of the bends are also presented.

Mini UAVs in the ≺20 kg category are widely operated by military and civilian organizations, usually for surveillance purposes, and many are electrically powered for low acoustic and infra-red observability. Despite recent improvements in Lithium Polymer battery technology, endurance is still usually limited to around 1 hour for fixed wing vehicles. For operational reasons, it is desirable to increase endurance and fuel cells can provide the high energy density necessary to do this. Many examples of PEMFC (Polymer Electrolyte Membrane Fuel Cell)-powered UAVs have been flown in recent years, all relying on a supply of hydrogen on board the UAV, giving the usual safety and weight concerns surrounding hydrogen storage.

This paper describes the integration of a Modal Energy and Emissions Model (MEEM) into a hybrid-electric vehicle simulation model, the PNGV System Analytic Toolkits (PSAT). PSAT is a forward-looking computer simulation model for advanced-technology vehicles. MEEM is a vehicle fuel-consumption and emissions model developed by one of the authors for internal-combustion-engine (ICE) -powered vehicles. MEEM engine simulation module uses a power-demand physical model based on a parameterized analytical representation of engine fuel and emissions production. One major advantage of MEEM is that it does not rely on steady-state engine maps, which are usually not available for most production vehicles; rather, it depends on a list of engine parameters that are calibrated based on regular vehicle dynamometer testing. The integrated PSAT-MEEM model can be used effectively to predict fuel consumption and emissions of various ICE-powered vehicles with both conventional and hybrid power trains.

This paper describes a general method for programming robot motions in an industrial environment. The purpose of this study was the off-line programming automation of riveting machines for Airbus (A320-A340) panels and sub-assemblies. Providing the initial and goal configuration of the robot on the Airbus part, the method determines a collision-free path taking into account CAD models of both the robot and Airbus parts. This method, based on the attractive potential field concept and the random motion technique, has been implemented on a robotic simulation software.

The demand for more security, economy, and comfort as well as for a reduced environmental impact increases the importance of electronic components for vehicles. The development of such systems is determined by the requirement of an improved functionality and co-requisite the demand for limited costs. In order to fulfil these demands and taking into consideration the increase of complexity and the melting together to a car wide web, Bosch is developing a structuring concept called CARTRONIC®. This concept is supposed to be open and neutral regarding automotive manufactures and suppliers. The analysis of vehicle control systems via this method is based on formal rules for structuring and modelling. The function-related aspect of CARTRONIC® was represented already at the SAE'98 World Congress. Furthermore the safety-related feature was introduced in more detail at the SAE'99 World Congress. The result of the analysis is an object structure of logical components with defined interfaces.

Torsional stiffness properties were developed for both a 53-foot box trailer and a 28-foot flatbed control trailer based on experimental measurements. In order to study the effect of torsional stiffness on the dynamics of a heavy truck vehicle dynamics computer model, static maneuvers were conducted comparing different torsional stiffness values to the original rigid vehicle model. Stiffness properties were first developed for a truck tractor model. It was found that the incorporation of a torsional stiffness model had only a minor effect on the overall tractor response for steady-state maneuvers up to 0.4 g lateral acceleration. The effect of torsional stiffness was also studied for the trailer portion of the existing model.

This paper describes a method of integrating an accelerator position sensor and an idle validation switch to optimize the coordination of these two functions in a vehicle throttle control system.

This paper describes an adaptive control strategy for improving the steering response of an automated vehicle steering controller. In order to achieve repeatable dynamic test results, precise steering inputs are necessary. This strategy provides the controller tuning parameters optimized for a particular vehicle's steering system. Having the capability to adaptively tune the steering controller for any vehicle installation provides an easy method for obtaining precise steering inputs for a wide range of vehicles, from small off-road utility vehicles to passenger vehicles to heavy trucks. The S.E.A. Ltd. Automated Steering Controller (ASC) is used exclusively in conducting this research. By recording the torque input to the steering system by the steering controller and the resulting steering angle during only a single test, the ASC is able to characterize the steering system of the test vehicle and create a computer model with appropriate parameters.

Ethanol can be converted into a 1:1:1 mixture of H2, CO, and CH4 at 300°C using a copper-nickel catalyst, a process known as “low-temperature ethanol reforming.” The hydrogen content of this mixture enables an engine to operate lean or with high levels of EGR, improving fuel economy and emissions. An onboard ethanol reformer- a catalyst module providing heat exchange with exhaust-was recently reported and shown to exhibit stable high conversion of ethanol driven by exhaust heat. This paper describes the successful integration and operation of a Ford 3.5L 3 TiVCT flex-fuel engine with a compact reformer and auxiliary hardware, fueled by E85. The system constitutes an integrated power system suitable for vehicle integration. The engine was operated on a mixture of E85 and reformate using a stoichiometric air-fuel ratio with internal EGR at a 12:1 compression ratio.

The electronics in the JCB Wheeled Loader represent an integration of the requirements of the operator, the needs for configuration on several models of loader in several languages, and the need for data collection and diagnostic capabilities. A number of challenging technologies are used in the electronics including a large custom LCD panel with backlighting, LED warning indicators, automatic 12V/24V operation, real-time clock recording of fault conditions, and CE approval. The Windows-based software tool allows settings to be altered and logged data to be viewed to monitor the operation of the loader and assist with diagnostics of faults.