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A simulation technology has been developed to enable prediction of galvanic corrosion in chassis parts where two different materials, iron and aluminum, come into contact with each other. When polarization curves representing a corrosive environment are input, this simulation technology calculates the corrosion current to flow and outputs the volume of aluminum corrosion to be formed near the iron-aluminum interface. The simulation makes it possible to predict the depth of corrosion that may occur in automobiles in the market.

Honda has developed an “Independent Left and Right Rear Toe Control System” that can achieve stable cornering performance and agile handling. We believe the issue that should be resolved in the next generation of ESC is the expansion of stability and agility into the general operation area. We examined how to accomplish this aim, and control of the independent rear toe angle was decided to be an appropriate method. In addition, a method for mounting the system without using a dedicated suspension was proposed. If left and right toe angles can be controlled independently, toe angle control and normal 4WS control become possible at the same time. In this paper, we will discuss the fundamental principle of independent toe angle control and the system configuration. Also, “INOMAMA Handling” (at driver's will) achieved by this system, as well as the fun and safe driving that are achieved as a result will be shown.

In this research, a three degree-of-freedom (DOF) rack-type electric-based power steering (EPS) model is developed. The model is coupled with a three DOF vehicle model and includes EPS maps as well as non-linear attributes such as vibration and friction characteristics of the steering system. The model is simulated using Matlab's Simulink. The vibration levels are quantified using on-vehicle straight-line test data where strain-gauge transducers are placed in the tie-rod ends. Full vehicle kinematic and compliance tests are used to verify the total steering system stiffness levels. Frequency response tests are used to adjust tire cornering stiffness levels as well as the tire dynamic characteristics such that vehicle static gain and yaw natural frequency are achieved. On-center discrete sinusoidal on-vehicle tests are used to further validate the model.

Recently vehicle development timeline is becoming shorter, so there is an urgent need to be able to develop vehicles with limited resources. This means the efficiency of the body structure development process must be improved. Specifically it is important to reduce the amount of design re-work required to meet performance targets as this can have a large influence on the body development time. In order to reduce the afore mentioned design re-work, we developed simple calculation models to apply a “V-Flow Development Process” to the preliminary stage design of the automobile body structure. The “V-Flow” advantages are as follows: (1) simple and easy to use, (2) defects are found at early stage, (3) avoids the downward flow of the defects. The advantage of preliminary stage design is that there is design flexibility since not many specifications have been determined yet.

The development and calibration of stress state-dependent failure criteria for advanced high-strength steel (AHSS) and aluminum alloys requires characterization under proportional loading conditions. Traditional tests to construct a forming limit diagram (FLD), such as Marciniak or Nakazima tests, are based upon identifying the onset of strain localization or a tensile instability (neck). However, the onset of localization is strongly dependent on the through-thickness strain gradient that can delay or suppress the formation of a tensile instability so that cracking may occur before localization. As a result, the material fracture limit becomes the effective forming limit in deformation modes with severe through-thickness strain gradients, and this is not considered in the traditional FLD. In this study, a novel bending test apparatus was developed based upon the VDA 238-100 specification to characterize fracture in plane strain bending using digital image correlation (DIC).

This study developed technology for simultaneously welding heterogeneous resin tubes in order to weld and integrate resin tubes with two different specifications (low temperature and high temperature). The aim of integration was cost and weight reduction. The cost reduction due to reducing the number of parts exceeded the increase in material cost due to a change to resin materials. Base material fracture of the resin tubes was set as the breaking format condition, and the welding parameters of the joint part rotations and the friction time between the joint part and the resin tubes were specified as the weld strength judgment standard. In addition, the fused thickness determined by observing the cross-section after welding was specified as the weld quality judgment standard. The range over which weld boundary peeling does not occur and weld strength is manifest was clarified by controlling the welding parameters and the fused thickness.

The SAE Fuel Cell Vehicle (FCV) Safety Working Group has been addressing FCV safety for over 9 years. The initial document, SAE J2578, was published in 2002. SAE J2578 has been valuable as a Recommended Practice for FCV development with regard to the identification of hazards and the definition of countermeasures to mitigate these hazards such that FCVs can be operated in the same manner as conventional gasoline internal combustion engine (ICE)-powered vehicles. SAE J2578 is currently being revised so that it will continue to be relevant as FCV development moves forward. For example, test methods were refined to verify the acceptability of hydrogen discharges when parking in residential garages and commercial structures and after crash tests prescribed by government regulation, and electrical requirements were updated to reflect the complexities of modern electrical circuits which interconnect both AC and DC circuits to improve efficiency and reduce cost.

The SAE FCV Safety Working Group has been addressing fuel cell vehicle (FCV) safety for over 8 years. The initial document, SAE J2578, was published in 2002. SAE J2578 has been valuable to FCV development with regard to the identification of hazards and the definition of countermeasures to mitigate these hazards such that FCVs can be operated in the same manner as conventional gasoline internal combustion engine (ICE)-powered vehicles. J2578 is currently being updated to clarify and update requirements so that it will continue to be relevant and useful in the future. An update to SAE J1766 for post-crash electrical safety was also published to reflect unique aspects of FCVs and to harmonize electrical requirements with international standards. In addition to revising SAE J2578 and J1766, the Working Group is also developing a new Technical Information Report (TIR) for vehicular hydrogen systems (SAE J2579).

More stringent heavy vehicle emissions legislation demands considerably higher performance for engine cooling systems. This paper presents a study of cooling airflow for a Freightliner Class 8 truck. The predicted radiator coolant inlet and charge-air-cooler outlet temperatures are in very good agreement with the measured data. The under hood flow behavior is described and potential areas of improvement leading to better cooling airflow performance are highlighted. The airflow simulation approach is based on the Lattice-Boltzmann Method (LBM) and is described in detail. It is shown that the presented simulation approach can provide accurate predictions of cooling airflow and coolant temperature across different fan speeds.

Heavy trucks are produced with a great variety of vehicle configurations, operate over a wide range of gross vehicle weight and sometimes function in extreme duty environments. Frontal crashes of heavy trucks can pose a threat to truck occupants when the vehicle strikes another large object such as bridge works, large natural features or another heavy-duty vehicle. Investigations of heavy truck frontal crashes indicate that the factors listed above all affect the outcome for the driver and the resulting damage to the truck Recently, a new chassis was introduced for on-highway heavy truck models that feature frontal airbag occupant protection. This introduction presented an opportunity to incorporate the knowledge gained from crash investigation into the process for developing the crash sensor's parameter settings.

The SAE FCV Safety Working Group has been addressing fuel cell vehicle (FCV) safety for over 7 years. The initial document, SAE J2578, was published in 2002. SAE J2578 has been valuable to the FCV development with regard to the identification of hazards and the definition of countermeasures to mitigate these hazards such that FCVs can be operated in the same manner as conventional gasoline IC-powered vehicles. The document is currently being updated to clarify and update requirements so that the document will continue to be relevant and useful in the future. In addition to developing draft revisions to SAE J2578, the working group has updated SAE J1766 and is developing a new recommended practice on vehicular hydrogen systems (SAE J2579). The documents are written from the standpoint of systems-level, performance-based requirements. A risk-based approach was used to identify potential electrical and fuel system hazards and provide criteria for acceptance.

The SAE Fuel Cell Vehicle (FCV) Safety Working Group has been addressing FCV safety for over 10 years. The initial document, SAE J2578, was published in 2002. SAE J2578 has been valuable as a Recommended Practice for FCV development with regard to the identification of hazards associated with the integration of hydrogen and electrical systems onto the vehicle and the definition of countermeasures to mitigate these hazards such that FCVs can be operated in the same manner as conventional gasoline internal combustion engine (ICE)-powered vehicles. An update to SAE J1766 for post-crash electrical safety was also published in 2008 to reflect unique aspects of FCVs and to harmonize electrical requirements with international standards. In addition to SAE J2578 and J1766, the SAE FCV Safety Working Group also developed a Technical Information Report (TIR) for vehicular hydrogen systems (SAE J2579).

The paper considers the implications of typical faults on the operation and control of a permanent magnet (PM) traction drive. The discussion is illustrated with analyses and test results taken from a vector controlled, imbedded magnet design of PM motor that has been prototyped for a future fuel cell powered mid size car. In particular the paper describes the outcome of an experimental investigation where a series of representative faults have been imposed on the prototype machine. The impact of the various faults and the subsequent fault control on the drive system are presented in terms of braking torque, and maximum current requirements.

A commercial vehicle's unexpected deviation from its current lane, often referred to simply as lane departure, can be a manifestation of any number of problems focused on either the vehicle (mechanical or electrical malfunction) or the driver (distraction or drowsiness). To address the topic of commercial vehicle lane departure, DaimlerChrysler Research, Freightliner and Odetics developed Lane Guidance™, a commercially available lane departure warning system. The Roll Advisor and Control (RA&C) Field Operational Test (FOT) as part of the United States Department of Transportation's Intelligent Vehicle Initiative (IVI) offered an excellent opportunity to evaluate the newly deployed Lane Guidance™ System with real world data. The goal of this evaluation was to understand the performance of the system under different environmental conditions such as rain, snow and night/daytime.

Sound Ergonomics is an important attribute and differentiator among trucks, because professional truck drivers spend many hours of their work time on the road driving. Ergonomics affects areas of driver safety, comfort, accommodation and performance. The purpose of this paper is to showcase the ergonomic principles, tools and process that were applied throughout the development cycle of Freightliner's new Medium Duty Truck: Business Class M2. An important centerpiece of the ergonomic process at Freightliner is RAMSIS, a 3-D Digital Human Modeling software. It allows effective evaluation of ergonomic issues in the CAD environment early on in the development cycle, thus reducing the risk of expensive re-designs at later stages in the vehicle development process. Several examples with RAMSIS will highlight the benefits of applying 3-D human modeling to the design process.

The purpose of this paper is to showcase the industrial design and ergonomic principles, tools and the processes that were concurrently applied throughout the development cycle of Thom”. Thomas Built Buses Engineering and Freightliner LLC Engineering groups worked interactively to optimize driver and passenger ergonomics, comfort and safety. Several examples are shown to highlight the benefits of applying 3-D human modeling to the design process. Resulting improvements of visibility, accommodation, and safety are shown.

Understanding external vehicle aerodynamics is an integral step in reducing overall vehicle fuel consumption. This is particularly true for long-haul commercial vehicles where an incremental decrease in drag can translate into significant fuel savings based on the number of miles traveled over the course of a truck's working life. The ability to critically analyze the air motion adjacent to commercial vehicles is a step toward understanding the overall affects of external aerodynamics on the entire vehicle. To achieve this understanding, the aerodynamics problem must be divided into manageable tasks that can each yield qualitative and quantitative results. A two-dimensional (2D) External Aerodynamics Tool (EAT) has been developed that enables computational fluid dynamics (CFD) simulations of commercial vehicles to be performed quickly and easily.

Recently public agencies have been promulgating idling bans in an effort to mitigate the environmental effects of heavy-duty truck idling. In order to make rational choices, regulators, manufacturers, and consumers will need to compare idling reduction strategies, such as truck stop electrification and auxiliary power units. Truck driver behaviors, such as idling time, idling location, and accessory use will significantly influence the cost-effectiveness of the various technology options. Truck driver attitudes toward idling and idling alternatives will influence adoption of the technologies. A pilot survey of 233 line-haul truck drivers was administered in Northern California as the first step in assessing truck driver behaviors and attitudes related to idling. Initial findings reveal that line-haul truck drivers idle primarily to power climate control.

EPA/DOE energy star program has effectively improved efficiency of home air conditioners by 25% with $25 billion annual saving due to the requirement of minimum SEER 10. The population of AC powered vehicles is estimated at around 180 million. The quantity may be even larger than that of home AC. Currently automotive AC seems t o work less efficiently with estimation for EER of 5 typically. If the Energy Star program could extend into automotive AC to promote energy efficiency, the result would be a significant energy saving valued at 3.38 billion gallons of gas ($5.4 billion) annually would be resulted. To find out what caused the situation, a contrastive study has been conducted on refrigerants thermal properties, system cycling performances etc. R134a used in automobiles may not be a key factor for such a negative result, but the AC compressors may be evidently a prominent consideration.

The fuel cell vehicle (FCV) has the potential to revolutionize the world's transportation systems. As choices are made on sources of fuel for FCVs it is important to consider the life-cycle implications of each option or system. This paper summarizes the methodology and results of a joint initiative to evaluate the life-cycle performance of 72 vehicle and fuel scenarios in 3 Canadian cities, comparing Proton Exchange Membrane (PEM) fuel cell vehicles and fuelling infrastructure with conventional and alternative fuel vehicles. The analysis is based on actual performance data of commercial and near-commercial technologies. The specific fuels investigated were gasoline, diesel, natural gas, methanol, hydrogen and electricity. The Pembina Institute's Life-Cycle Value Assessment (LCVA) methodology was used to compare the environmental, economic and social performance of each system.