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Journal Article

Safe and Secure Software Updates Over The Air for Electronic Brake Control Systems

2016-09-18
2016-01-1145
Vehicle manufacturers are suffering from increasing expenses for fixing software issues. This fact is mainly driving their desire to use mobile communication channels for doing Software Updates Over The Air (SOTA). Software updates today are typically done at vehicle service stations by connecting the vehicles’ electronic network via the On Board Diagnostic (OBD) interface to a service computer. These operations are done under the control of trained technicians. SOTA means that the update process must get handled by the driver. Two critical aspects need to get considered when doing SOTA at Electronic Brake Control (EBC) systems. Both will determine the acceptance of SOTA by legal authorities and by the passengers: The safety and security of the vehicle The availability of the vehicle for the passengers The security aspect includes the necessity to protect the vehicle and the manufacturers IP from unwanted attacks.
Journal Article

Review of Prior Studies of Fuel Effects on Vehicle Emissions

2009-04-20
2009-01-1181
A literature review was conducted to survey recent research on the effects of fuel properties on exhaust emissions from gasoline and diesel vehicles, on-road and off-road. Most of the literature has been published in SAE papers, although data have also been reported in other journals and government reports. A full report and database are available from the Coordinating Research Council (www.crcao.org). The review identified areas of agreement and disagreement in the literature and evaluated the adequacy of experimental design and analysis of results. Areas where additional research would be helpful in defining fuel effects are also identified. In many of the research programs carried out to evaluate the effect of new blendstocks, the fuel components were splash blended in fully formulated fuels. This approach makes it extremely difficult to determine the exact cause of the emissions benefit or debit.
Journal Article

Optimal Use of E85 in a Turbocharged Direct Injection Engine

2009-04-20
2009-01-1490
Ford Motor Company is introducing “EcoBoost” gasoline turbocharged direct injection (GTDI) engine technology in the 2010 Lincoln MKS. A logical enhancement of EcoBoost technology is the use of E85 for knock mitigation. The subject of this paper is the optimal use of E85 by using two fuel systems in the same EcoBoost engine: port fuel injection (PFI) of gasoline and direct injection (DI) of E85. Gasoline PFI is used for starting and light-medium load operation, while E85 DI is used only as required during high load operation to avoid knock. Direct injection of E85 (a commercially available blend of ∼85% ethanol and ∼15% gasoline) is extremely effective in suppressing knock, due to ethanol's high inherent octane and its high heat of vaporization, which results in substantial cooling of the charge. As a result, the compression ratio (CR) can be increased and higher boost levels can be used.
Journal Article

Development and Testing of an Innovative Oil Condition Sensor

2009-04-20
2009-01-1466
In order to detect degradation of engine oil lubricant, bench testing along with a number of diesel-powered Ford trucks were instruments and tested. The purpose of the bench testing was primarily to determine performance aspects such as repeatability, hysteresis effects and so on. Vehicle testing was conducted by designing and installing a separate oil reservoir along with a circulation system which was mounted in the vicinity of the oil pan. An innovative oil sensor was directly installed on the reservoir which can measure five (5) independent oil parameters (viscosity, density, permittivity, conductance, temperature). In addition, the concept is capable of detecting the oil level continuously during normal engine operation. The sensing system consists of an ultrasonic transducer for the oil level detection as well as a Tuning Fork mechanical resonator for the oil condition measurement.
Journal Article

Empirical Modeling of Transient Emissions and Transient Response for Transient Optimization

2009-04-20
2009-01-1508
Empirical models for engine-out oxides of Nitrogen (NOx) and smoke emissions have been developed for the purpose of minimizing transient emissions while maintaining transient response. Three major issues have been addressed: data acquisition, data processing and modeling method. Real and virtual transient parameters have been identified for acquisition. Accounting for the phase shift between transient engine events and transient emission measurements has been shown to be very important to the quality of model predictions. Several methods have been employed to account for the transient transport delays and sensor lags which constitute the phase shift. Finally several different empirical modeling methods have been used to determine the most suitable modeling method for transient emissions. These modeling methods include several kinds of neural networks, global regression and localized regression.
Journal Article

Development and Advances of a V-Flow FC Stack for FCX Clarity

2009-04-20
2009-01-1010
Honda has succeeded in developing the new fuel cell (FC) vehicle designed into a dynamic, full-cabin sedan, the FCX Clarity, originating from the new V Flow FC platform. The key technology is V Flow FC Stack, featuring V Flow cell structure in which the fuel gases run from top to bottom vertically through the wave flow-channels. According to this unique structure, the fuel cell stack sits longitudinally along the center tunnel, and a Vertebral layout has emerged. The Vertebral layout results in Volume efficient package and low-floor platform. The V Flow FC stack has achieved a high output of 100kW and improved the output density with 50% by volume and 67% by mass, compared to the previous 2005 model. The V Flow cell structure utilizes gravity for water drainage and reduces the channel depth creating thinner cells. The wave-shaped vertical gas flow channel provides horizontal and more efficient coolant flow distribution allowing the reduction of the number of cooling layer.
Journal Article

Identification and Robust Control of LPG Fuel Supply System

2009-04-20
2009-01-1025
This paper proposes a new returnless LPG fuel supply system designed to increase the efficiency of current LPG engines. With a conventional engine fuel supply system, the fuel pump is driven at a certain speed to pressurize the fuel to an excessive level, and excess fuel that is discharged from the fuel pump but not injected from the injector is returned to the fuel tank via a pressure regulator and a return line. This arrangement keeps the pressure in the fuel supply line at a constant level. Accordingly, during engine idling, fuel cut-off or other times when very little or no fuel is injected from the injector, nearly all the fuel discharged from the fuel pump is returned to the fuel tank via the pressure regulator and return line. Therefore, the energy (electric power) applied to drive the fuel pump is wastefully consumed. Moreover, returning a large amount of excess fuel to the fuel tank can raise the fuel temperature in the tank, causing the fuel to evaporate.
Journal Article

Advanced Control System of Variable Compression Ratio (VCR) Engine with Dual Piston Mechanism

2009-04-20
2009-01-1063
A dual piston Variable Compression Ratio (VCR) engine has been newly developed. This compact VCR system uses the inertia force and hydraulic pressure accompanying the reciprocating motion of the piston to raise and lower the outer piston and switches the compression ratio in two stages. For the torque characteristic enhancement and the knocking prevention when the compression ratio is being switched, it is necessary to carry out engine controls based on accurate compression ratio judgment. In order to accurately judge compression ratio switching timing, a control system employing the Hidden Markov Model (HMM) was used to analyze vibration generated during the compression ratio switching. Also, in order to realize smooth torque characteristics, an ignition timing control system that separately controls each cylinder and simultaneously performs knocking control was constructed.
Journal Article

Active Heat Sink for Automotive Electronics

2009-04-20
2009-01-0965
This paper reports an active heat sink (AHS) that allows high-density electronic components to operate at a stable temperature over a broad range of ambient conditions. AHS receives heat at high flux and transfers it at reduced flux to environment, coolant fluid (e.g., air or engine coolant), or structures. Temperature of the heat load can be controlled electronically. Target applications for AHS include thermal management of the new class of high-power electronics being developed for electric hybrid vehicles. AHS also enables precise control over junction temperature (and, thus, light color) of high-power light-emitting diodes (LED) used for solid-state headlights and allows for compact air-cooled heat sinks. Depending on the configuration, AHS thermal resistance can be as low as 0.1 degC/W. AHS physics, engineering design, and performance simulations are presented.
Journal Article

Herschel Heaters Control Modeling and Correlation

2009-07-12
2009-01-2348
Herschel and Planck satellites have recently undergone the thermal vacuum and thermal balance (TVTB) test which was performed in the ESA-ESTEC Large Space Simulator for Herschel and in Centre Spatial de Liège (CSL) for Planck. One of the specific targets of the Herschel test was the verification of the thermal stability of two HIFI units (required to be better than 3.10−4 °C/s) and of the Star Tracker mounting plate (required to be better than 2.5.10−3 °C/s), with particular attention on the performance of the relevant feedback control loops. Control system design and model predictions are presented and compared against the test results. Further discussion on the requirement verification is provided.
Journal Article

Analyses of Several Space Radiation-Mitigating Materials: Computational and Experimental Results

2009-07-12
2009-01-2338
Long-term exposure to the space radiation environment poses deleterious effects to both humans and space systems. The major sources of the radiation effects come from high energy galactic cosmic radiation and solar proton events. In this paper we investigate the radiation-mitigation properties of several shielding materials for possible use in spacecraft design, surface habitats, surface rovers, spacesuits, and temporary shelters. A discussion of the space radiation environment is presented in detail. Parametric radiation shielding analyses are presented using the NASA HZETRN 2005 code and are compared with ground-based experimental test results using the Loma Linda University Proton Therapy facility.
Journal Article

Effect of Illumination Angle on the Performance of Dusted Thermal Control Surfaces in a Simulated Lunar Environment

2009-07-12
2009-01-2420
JSC-1A lunar simulant has been applied to AZ93 and AgFEP thermal control surfaces on aluminum substrates in a simulated lunar environment. The temperature of these surfaces was monitored as they were heated with a solar simulator using varying angles of incidence and cooled in a 30 K coldbox. Thermal modeling was used to determine the solar absorptivity (a) and infrared emissivity (e) of the thermal control surfaces in both their clean and dusted states. It was found that even a sub-monolayer of dust can significantly raise the α of either type of surface. A full monolayer can increase the α/ε ratio by a factor of 3–4 over a clean surface. Little angular dependence of the α of pristine thermal control surfaces for both AZ93 and AgFEP was observed, at least until 30° from the surface. The dusted surfaces showed the most angular dependence of α when the incidence angle was in the range of 25° to 35°.
Journal Article

Hollow Fiber Space Suit Water Membrane Evaporator Development for Lunar Missions

2009-07-12
2009-01-2371
The Space Suit Water Membrane Evaporator (SWME) is a baseline heat rejection technology that was selected to develop the Constellation Program lunar suit. The Hollow Fiber (HoFi) SWME is being considered for service in the Constellation Space Suit Element Portable Life Support Subsystem to provide cooling to the thermal loop via water evaporation to the vacuum of space. Previous work [1] described the test methodology and planning that are entailed in comparing the test performance of three commercially available HoFi materials as alternatives to the sheet membrane prototype for SWME: (1) porous hydrophobic polypropylene, (2) porous hydrophobic polysulfone, and (3) ion exchange through nonporous hydrophilic-modified Nafion®.
Journal Article

Results of Multifunctional Condensing Heat Exchanger for Water Recovery Applications

2009-07-12
2009-01-2383
Humidity control within confined spaces is of great importance for current NASA environmental control systems and future exploration applications. The engineered multifunction surfaces (MFS) developed by ORBITEC is a technology that produces hydrophilic and antimicrobial surface properties on a variety of substrate materials. These properties combined with capillary geometry create the basis for a passive condensing heat exchanger (CHX) for applications in reduced gravity environments, eliminating the need for mechanical separators and particulate-based coatings. The technology may also be used to produce hydrophilic and biocidal surface properties on a range of materials for a variety of applications where bacteria and biofilms proliferate, and surface wetting is beneficial.
Journal Article

Mars Science Laboratory Mechanically Pumped Fluid Loop for Thermal Control - Design, Implementation, and Testing

2009-07-12
2009-01-2437
The Mars Science Laboratory (MSL) mission to land a large rover on Mars is being prepared for Launch in 2011. A Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) on the rover provides an electrical power of 110 W for use in the rover and the science payload. Unlike the solar arrays, MMRTG provides a constant electrical power during both day and night for all seasons (year around) and latitudes. The MMRTG dissipates about 2000 W of waste heat to produce the desired electrical power. One of the challenges for MSL Rover is the thermal management of the large amount of MMRTG waste heat. During operations on the surface of Mars this heat can be harnessed to maintain the rover and the science payload within their allowable limits during nights and winters without the use of electrical survival heaters. A mechanically pumped fluid loop heat rejection and recovery system (HRS) is used to pick up some of this waste heat and supply it to the rover and payload.
Journal Article

Standardization of Graphics for Service Information and Translation Expense Reduction

2009-10-06
2009-01-2857
The cost of human natural language translation of Service Information, Assembly Instructions, Training Materials, Operator Manuals and other similar documents is a major expense for manufacturers. One translation avoidance method involves replacing most of a document’s text with still and/or animated graphics. While the graphics with minimum text concept has savings potential, clarity of communication must be maintained for widespread application of this technique. The necessary clarity should be achieved if standards are established for the symbols and graphical conventions used. This paper provides an example of a repair procedure documented using the graphics with minimum text paradigm, describes many of the anticipated standards and provides an update on the progress towards achieving a standard development project.
Journal Article

Fuel Economy Benefits of a Flywheel & CVT Based Mechanical Hybrid for City Bus and Commercial Vehicle Applications

2009-10-06
2009-01-2868
Hybrid drivetrain systems are becoming increasingly prevalent in Automotive and Commercial Vehicle applications and have also been introduced for the 2009 Formula1 motorsport season. The F1 development has the clear intent of directing technical development in motorsport to impact the key issue of fuel efficiency in mainstream vehicles. In order to promote all technical developments, the type of system (electrical, mechanical, hydraulic, etc) for the F1 application has not been specified. A significant outcome of this action is renewed interest and development of mechanical hybrid systems comprising a high speed composite flywheel and a full-toroidal traction drive Continuously Variable Transmission (CVT). A flywheel based mechanical hybrid has few system components, low system costs, low weight and dispenses with the energy state changes of electrical systems producing a highly efficient and power dense hybrid system.
Journal Article

Current and New Approaches for Brake Noise Evaluation and Rating

2009-10-11
2009-01-3037
Predominant brake noise evaluation and rating was developed many years ago and no longer fulfills the need of modern development work. An extended description of a noisy brake event (European expert group guideline EKB 3006) and a standardized test data exchange format, allowing the comparison of different source test results (EKB 3008) are presented. Today's noise rating systems are described and compared by selected examples. The paper proposes an open 4 level noise rating system (EKB 3007). It starts with simple occurrence statistics, noise rating based on sound levels, situational noise rating including duration and finally based on the human perception, described by psychoacoustics.
Journal Article

Real Time Implementation of DOC-DPF Models on a Production-Intent ECU for Controls and Diagnostics of a PM Emission Control System

2009-10-06
2009-01-2904
This paper describes the joint development by Tenneco and Pi Shurlok of a complete diesel engine aftertreatment system for controlling particulate matter emissions. The system consists of a DOC, DPF, sensors, controller and an exhaust fuel injection system to allow active DPF regeneration. The mechanical components were designed for flow uniformity, low backpressure and component durability. The overall package is intended as a complete PM control system solution for OEMs, which does not require any significant additions to the OEM's engine control strategies and minimizes integration complexity. Thus, to make it easier to adapt to different engine platforms, ranging from small off-road vehicle engines to large locomotive engines, model-based control algorithms were developed in preference to map-based controls.
Journal Article

Brake Timing Measurements for a Tractor-Semitrailer Under Emergency Braking

2009-10-06
2009-01-2918
The timing and associated levels of braking between initial brake pedal application and actual maximum braking at the wheels for a tractor-semitrailer are important parameters in understanding vehicle performance and response. This paper presents detailed brake timing information obtained from full scale instrumented testing of a tractor-semitrailer under various conditions of load and speed. Brake timing at steer, drive and semitrailer brake positions is analyzed for each of the tested conditions. The study further seeks to compare the full scale test data to predicted response from detailed heavy truck computer vehicle dynamics simulation models available in commercial software packages in order to validate the model's brake timing parameters. The brake timing data was collected during several days of full scale instrumented testing of a tractor-semitrailer performed at the Transportation Research Center, in East Liberty, Ohio.
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