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Honda has developed a new next-generation 3.5 L V6 gasoline engine using our latest Earth Dreams Technology. The overall design objective for the engine was to reduce CO₂ emissions and provide driving exhilaration. The Earth Dreams Technology concept is to increase fuel economy while reducing emissions. To achieve this and provide an exhilarating driving experience, 3-stage Variable Valve Timing and Lift Electronic Control (VTEC) was combined with the Variable Cylinder Management (VCM) system. This valve train technology in conjunction with Direct Injection (DI), resulted in dramatic improvements in output (a 3.3% increase) and combined mode fuel economy (20% reduction). Helping to achieve Midsize Luxury Sedan level NV, a new mount system was developed to reduce engine vibrations during three-cylinder-mode operation. In this paper, we will explain the 3-stage VTEC with VCM + DI system, friction reducing technology, and the structure and benefit of the new engine mount system.

Considerable improvements can be obtained in battery performance for hybrid electric vehicles (HEVs) by employing an electrochemistry-transport model based on a multi-physics modeling framework and ultrafast numerical algorithms. One important advantage of this approach over the lumped equivalent circuit (or look-up table) approach is the ability of the former to adapt to changes in design and control. In this work, we present mathematical and numerical details of our approach, and demonstrate the robustness of this battery model in simulation of short-pulse charge/discharge characteristic of HEV driving cycles under room and low temperatures.

A simulation tool has been developed for predicting steering effort of a vehicle during steering power-assist system failure. The vehicle system is modeled with the inclusion of a system-level vehicle model and a steering system model that are linked together through the steering moment at the kingpin and front road wheel angle. A driver model has also been designed to provide closed-loop steering angular input to make the car follow a certain target path. The simulation model is correlated well with actual vehicle tests under various steering input and lateral acceleration conditions. Also illustrated are some examples of comparison between measured and simulated sensitivity study for selected factors.

Vehicle-to-Vehicle (V2V) safety application research based on short range real-time communication has been researched for over a decade. Examples of V2V applications include Electronic Emergency Brake Light, Do Not Pass Warning, Lane Departure Warning, and Intersection Movement Assist. It is hoped that these applications, whether present as warning or intervention, will help reduce the incidence of traffic collisions, fatalities, injuries, and property damage. The safety benefits of these applications will likely depend on many factors, such as usability, market penetration, driver acceptance, and reliability. Some applications, such as DNPW and IMA, require a longer communication range to be effective. In addition, Dedicated Short Range Communications (DSRC) may be required to communicate without direct line of sight. The signal needs to overcome shadowing effects of other vehicles and buildings that are in the way.

A series of eight sled tests was conducted using Hybrid III dummies and cadavers in order to examine the influence of foot placement on the brake pedal in frontal collisions. The brake pedal in the sled runs was fixed in a fully depressed position and the occupants' muscles were not tensed. The cadaver limbs and the Hybrid III lower extremities with 45° ankle and soft joint-stop were extensively instrumented to determine response during the crash event. Brake pedal reaction forces were measured using a six-axis load cell and high speed film was used for kinematic analysis of the crashes. Four right foot positions were identified from previous simulation studies as those orientations most likely to induce injury. In each test, the left foot was positioned on a simulated footrest, acting as a control variable that produced repeatable results in all dummy tests. Each of the different right foot orientations resulted in different loads and motions of the right leg and foot.

An Articulated Total Body frontal crash simulation was created with the dummy's right foot placed on the brake pedal. This study examined how interaction of the driver's foot with the brake pedal influenced the behavior of the lower extremities in frontal collisions. Braking parameters considered in the study included foot position on the pedal, whether or not the occupant's muscles were tensed and if the brake pedal was rigid or was allowed to depress. Two basic foot positions were identified as most likely to induce injury of the lower limb. One represented a foot that was pivoted about the heel from the gas pedal to the brake pedal. The other position replicated a foot that was lifted from the gas pedal to the brake pedal, resulting in an initial gap between the heel and floor. Both positions resulted in different loads and behavior of the foot, indicating that driver pre-impact position is a contributing factor to one's injury risk.

The cost of fuel and the desire for fuel efficiency continue to drive automobile manufacturers to invest in and to prioritize vehicle designs and performance. There has long been a fundamental understanding that aerodynamic efficiency (drag) has an effect on this phenomenon. The focus of this paper is to demonstrate how emergent aerodynamic performance calculation tools can be efficiently and effectively utilized for realizing improvements to vehicle performance, thereby enhancing customer satisfaction and societal acceptance. These tools include Computational Fluid Dynamic analysis (CFD) which further includes visualization techniques, shape deformation, DOE, and optimization methods, among others.

Today's fuel cell powered vehicles typically utilize compressed hydrogen storage systems with a nominal working pressure of either 35MPa or 70Mpa. This coexistence of working pressures has, in a large part, developed in isolation, in that automakers have primarily considered vehicle side issues when choosing the storage system pressure. This study looks at hydrogen fueling from a holistic perspective by considering both vehicle side and station side issues with the goal to determine an optimum hydrogen working pressure. The approach utilized is to first conduct a data driven study of vehicle fueling at different working pressures and ambient temperatures to determine the vehicle and thermodynamic considerations of hydrogen fueling. This data is then contrasted with the hydrogen station hardware required to perform fueling at these temperatures and pressures.

Crucial specifications of an engine are spread widely in various subsystems, such as cooling system, intake and exhaust system, combustion system, etc. Well-informed design decision and optimized design solution cannot be reached without considering interactions among subsystems. Even though significant progresses on CAE technologies have been made to address physical and chemical phenomena in each subsystem, there are few studies in literature to model an engine with a reasonable coverage of subsystems in an integrated fashion. The necessity of such approach is justified from two aspects. Firstly, modifications in one subsystem could result in changes in other subsystems. Secondly, frequently due to experimental constraints or availability of prototypes which is the case for new engine design, boundary conditions for a subsystem of interest can only be obtained from integrated numerical simulations with other subsystems.

Improvement of engine cycle thermal efficiency is an effective way to increase engine torque and to reduce fuel consumption simultaneously. However, the extent of the improvement is limited by engine knock, which is more evident at low engine speeds when combustion flame propagation is relatively slow. To prevent engine damage due to knock, the spark ignition timing of a gasoline engine is usually controlled by a knock sensor. Therefore, an engine's ignition timing cannot be set freely to achieve best engine performance and fuel economy. Whether ignition timings for a multi-cylinder engine are the same or can be set differently for each cylinder, it is not desirable for each cylinder has big deviation from the median with respect to knock tendency. It is apparent that effective measures to improve engine knock toughness should address both uniformity of all cylinders of a multi-cylinder engine and improvement of median knock toughness.

Currently, car bodies require further weight reduction in order to support increasing fuel economy requirements. An efficient way for light weight body design is to include body member size as a design variable in addition to part thickness. However it is currently difficult for finite element (FE) models to change member size even using current morphing techniques. To break through this challenge, a hybrid modeling approach was developed which combines shell and beam element representations of body structural members. The original member shell element thickness was decreased by 40%. Then the stiffness reduction caused by this change is offset by beam elements incorporated inside these members. These beams can represent the stiffness change due to new cross sectional dimensions or orientations without changing the original shell elements, thus avoiding modeling instabilities that can occur from morphing.

The objectives of a new generation of light trucks required the development of a new platform chassis, using advances in packaging, manufacturing efficiency, mass reduction, fuel efficiency, noise and vibration toughness, and ride comfort, while maintaining the vehicle's fun-to-drive character. This paper outlines the chassis component and packaging integration, light weight material application with structural optimization, as well as technical concepts executed to improve performance. Key component focus points are axles and bearings, wheels, tires, suspensions, brakes, engine cradles and sub-frames, steering systems, mechanical controls, and fuel and exhaust systems.

This paper describes the new Honda R&D Americas Scale Model Wind Tunnel (SWT). To help address Honda's ongoing need to improve fuel economy, reduce the driving force of a vehicle, and decrease product development time, the wind tunnel was developed and implemented to achieve high accuracy aerodynamic predictions for product development and a significantly improved capability for vehicle aerodynamics research. The SWT can accommodate model scales up to 50%. The ¾-open jet test section has a top speed of 250 km/h, a 5-belt moving ground plane with a long center belt for proper wake simulation, a test section designed specifically for very low static pressure gradient, three separate dynamic pressure measurement systems for state-of-the-art blockage corrections, and an overhead traverse for specialized measurement activities. This paper describes the decision process that led to the SWT, key commissioning results, and performance validation results with models installed.

Test-driving is a specialized art. Automotive manufactures, parts suppliers, and tire manufacturers employ test drivers to evaluate their products in a variety of circumstances. But Honda and some other firms prefer the automotive engineer test his own product. This gives direct feedback and provides a better “feel” for how the vehicle reacts. It produces a better car and a better engineer. Some Formula One teams send their race engineers to a racing school. Test drivers can be trained at commercial racing schools. These effectively teach students to drive at high speeds near the limit of the vehicle. The test driver must have the skills to perform a test with minimal danger to the driver and the vehicle. But the demands of a test driver are not the same as a racing car driver, though many test drivers also race. The test driver must evaluate the vehicle as well as drive fast. The test driver must faithfully execute a test plan while observing vehicle behavior.

Thermodynamic analysis of equilibrium products and heat requirements is conducted for C8H18 (octane), CH4O (methanol), C2H6O (ethanol) and C3H8 (propane) at specified temperature and pressure. The equilibrium calculation utilizes the NASA equilibrium code by Gordon and MacBride. The temperature range is from 600 to 1700 K, and the pressure is set at 1 bar. The equilibrium calculation shows that the adiabatic temperatures are generally below 1300 K, except for C2H6O and C3H8 at their respective partial oxidation conditions considered in this paper. Calculation also shows that the presence of H2O in the reactant mixture yields high conversion of H2 at temperature above 1200 K, and above which the H2 mole fraction is relatively independent of the mixture temperature. Negligible C(graphite) is predicted for conditions with temperature above 1200 K.

Currently, a number of automobile OEMs have been equipped motorized seatbelt systems with volume-production vehicles. Since the current systems are generally initiated by the activation of the automatic collision brakes, or the brake assist systems; the benefit of those systems is limited solely in pre-crash phase. To enhance the effectiveness of the system, we attempted to develop a motorized seatbelt system which enables to control retracing force according to various situations during driving. The present system enables to accomplish both the occupants' comfort and protection performance throughout their driving from when it is buckled to when unbuckled and stored, or during both routine and sport driving, as well as pre-crash phase. Moreover, it was confirmed that lateral occupants' excursion during driving was reduced by up to 50% with the present system.

Vehicle-to-Grid (V2G) technology is expected to play a role in addressing the imbalance between periods of peak demand and peak supply on the electricity grid. V2G technology enables two-way power flow between the grid and the high-power, high-capacity propulsion batteries in an electrified vehicle. That is, V2G allows the vehicle to store electricity during peak supply periods, and then discharge it back into the grid during peak demand periods. The authors have performed an architectural design and a modeling and simulation study for a bi-directional wireless charging system for V2G applications. This research activity aims to adapt an existing SAE J2954 compatible uni-directional system design to enable bi-directional wireless power transfer with minimum impact to system cost, while maintaining full compatibility with the requirements of SAE J2954.

To address challenges related to refueling with compressed hydrogen, a simple, analytical method has been developed that allows a hydrogen station to directly and accurately calculate an end-of-fill temperature in a hydrogen tank and thereby maximize the fill quantity and minimize the refueling time. This is referred to as the MC Fueling Method, where MC represents total heat capacity. The MC Method incorporates a set of thermodynamic parameters for the tank system that are used by the station in a simple analytical equation along with measured values of dispensed hydrogen temperature and pressure at the station. These parameters can be communicated to the hydrogen station either directly from the vehicle or from a database that is accessible by the station. Because the MC Method is based on direct measurements of actual thermodynamic conditions at the station, and quantified thermodynamic behavior of the tank system, highly accurate tank filling results can be achieved.

Recreational Off-Highway Vehicles (ROVs), since their introduction onto the market in the late-1990s, have been related to over 300 fatalities with the majority occurring in vehicle rollover. In recent years several organizations made attempts to improve ROV safety. This paper is intended to evaluate ejection mitigation measures considered by the ROV manufacturers. Evaluated countermeasures include two types of occupant restraints (three and four point) and two structural barriers (torso bar, door with net). The Rollover protection structure (ROPS) provided by the manufacturer was attached to a Dynamic Rollover Test System (DRoTS), and a full factorial series of roll/drop/catch tests was performed. The ROV buck was equipped with two Hybrid III dummies, a 5th percentile female and a 95th percentile male. Additionally, occupant and vehicle kinematics were recorded using optoelectronic stereophotogrammetric camera system.