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The WorldSID dummy can be equipped with both a pubic and a sacroiliac joint (S-I joint) loadcell. Although a pubic force criterion and the associated injury risk curve are currently available and used in regulation (ECE95, FMVSS214), as of today injury mechanisms, injury criteria, and injury assessment reference values are not available for the sacroiliac joint itself. The aim of this study was to investigate the sacroiliac joint injury mechanism. Three configurations were identified from full-scale car crashes conducted with the WorldSID 50th percentile male where the force passing through the pubis in all three tests was approximately 1500 N while the sacroiliac Fy / Mx peak values were 4500 N / 50 Nm, 2400 N / 130 Nm, and 5300 N / 150 Nm, respectively. These tests were reproduced using a 150 kg guided probe impacting Post Mortem Human Subjects (PMHS) at 8 m/s, 5.4 m/s and 7.5 m/s.

Future Automotive Systems Technology Simulator (FASTSim) is a free and open-source tool developed by National Renewable Energy Lab (NREL). Among the attractive capabilities of the FASTSim is that it can perform computationally efficient fuel economy simulations of automotive vehicles with reasonable accuracy for standard or arbitrary drive cycles. The modeling capability includes vehicles with various types of powertrains such as: conventional vehicles (CVs), hybrid-electric vehicles (HEVs), plugin hybrid electric vehicles (PHEVs) and battery-only electric vehicles (BEVs). The public version of FASTSim available from NREL is implemented in Excel, which achieves the goal of good accessibility to a broad audience, but has some limitations, including: i) bottleneck in computations when importing arbitrary drive cycles, ii) slower computations in general than other scripting or programming languages, and iii) less portable to integration with other applications and/or other platforms.

A new 4.0 liter V8 engine, 1UZ-FE, has been developed for the luxury sedan, LEXUS LS400. The engine has 4 camshafts and 32 valves, and weighs only 195 kg (430 lbs) having many light alloy components and carefully designed configurations. The appropriate engine displacement and high technology adopted throughout from design to manufacturing process enable the LS400 to run powerfully with excellent fuel economy and a pleasant sounds. It develops 250HP at 5600 rpm and 260ft-lbs of torque at 4400 rpm, and its fuel economy figure, well exceeds the EPA's tax charge level of 22.5mpg. These figures have been achieved through the newest technologies applied to every part of the design, such as: Well studied intake and exhaust systems, centrally located spark plug in the TOYOTA original four-valve combustion chamber, which has a narrow valve including angle, and low friction components like aluminum alloy valve lifters and well balanced moving parts.

Many efforts have been made to understand the mechanism of whiplash injury. Recently, the cervical facet joint capsules have been focused on as a potential site of injury. An experimental approach has been taken to analyze the vertebral motion and to estimate joint capsule stretch that was thought to be a potential cause of pain. The purpose of this study is to analyze the kinematics of the cervical facet joint using a human FE model in order to better understand the injury mechanism. The Total Human Model for Safety (THUMS) was used to visually analyze the local and global kinematics of the spine. Soft tissues in the neck were newly modeled and introduced into THUMS for estimating the loading level in rear impacts. The model was first validated against human test data in the literature by comparing vertebrae motion as well as head and neck responses. Joint capsule strain was estimated from a maximum principal strain output from the elements representing the capsule tissues.

This paper analyzed the mechanisms of injury in high speed, right-lateral impacts of stock car auto racing, and interaction of the occupant and the seat system for the purpose of reducing the risk of injury, primarily rib fractures. Many safety improvements have been made to stock car racing recently, including the Head and Neck Support devices (HANS®), the 6-point restraint harnesses, and the implementation of the SAFER Barrier. These improvements have contributed greatly to mitigating injury during the race crash event. However, there is still potential to improve the seat structure and the understanding of the interaction between the driver and the seat in the continuation of making racing safety improvements. This is particularly true in the case of right-lateral impacts where the primary interaction is between the seat supports and the driver and where the chest is the primary region of injury.

Recently, the role of ECU(Electronic Control Unit) on vehicles has been becoming more important year by year in order to meet the requirements for safety and the environmental matters. Particularly, the ECU of Engine Management Systems has been becoming indispensable in order to realize high performance, low fuel consumption and low exhaust emission. Therefore, the size of software has also been increasing, and been becoming more complex and complicated. As the ECU software size becomes large and complex, the verification and validation of the software by using the current development method has been becoming more difficult. Especially it has been becoming more difficult to validate the Real-time property of the software. The Real-time property means whether the execution of the software is in time for the deadline which is decided on the software design.

Electric drive vehicles (EDV) have the potential to greatly reduce greenhouse gas (GHG) emissions and thus, there are many policies in place to encourage the purchase and use of gasoline-hybrid, battery, plug-in hybrid, and fuel cell electric vehicles. But not all vehicles are the same, and households use vehicles in very different ways. What if policies took these differences into consideration with the goal of further reducing GHG emissions? This paper attempts to answer two questions: i) are there certain households that, by switching from a conventional vehicle to an EDV, would result in a comparatively large GHG reduction (as compared to other households making that switch), and, if so, ii) how large is the difference in GHG reductions? The paper considers over 65,000 actual GPS trip traces (generated by one-second interval recording of the speed of approximately 2,900 vehicles) collected by the 2013 California Household Travel Survey (CHTS).

Posterior translation of the tibia with respect to the femur can stretch the posterior cruciate ligament (PCL). Fifteen millimeters of relative displacement between the femur and tibia is known as the Injury Assessment Reference Value (IARV) for the PCL injury. Since the anterior protuberance of the tibial plateau can be the first site of contact when the knee is flexed, the knee bolster is generally designed with an inclined surface so as not to directly load the projection in frontal crashes. It should be noted, however, that the initial flexion angle of the occupant knee can vary among individuals and the knee flexion angle can change due to the occupant motion. The behavior of the tibial protuberance related to the knee flexion angle has not been described yet. The instantaneous angle of the knee joint at the timing of restraining the knee should be known to manage the geometry and functions of knee restraint devices.

Previous studies have investigated the impacts of biofuel usage on the performance, drivability and durability of modern diesel engines and exhaust after-treatment systems including test work with different types, concentrations and mixtures of bio fuel components. During this earlier work vehicle fuel filter blocking issues were encountered during a field trial using various types of EN 14214 compliant Fatty Acid Methyl Ester (FAME) blended into EN 590 diesel. This paper summarises a subsequent literature review that was carried out looking into potential causes of this filter blocking and further work that was then carried out to expand on the findings. From this, a laboratory study was carried out to assess the increase in fuel filter blocking tendency (FBT) when various FAMEs from mixed sources were blended into EN 590 diesel at different concentrations, including levels above those currently allowed in the European market.

Whinning gear noise(final gear noise), one of the causes for automobile interior noise is due to the exciting force of final gear kit and as a general countermeasure for this problem, a reduction of resonance level in transfer system and better meshing of gears have been utilized. However,vibration characteristics of final gear unit have not been considered much in this case. Authors have executed impacting test on final gear unit and confirmed its vibration characteristics. Based on this fact,vibration model consisting of bearings and gears spring system was constructed to evaluate vibration characteristics of final gear unit along with the results obtained from final gear unit of front engine,rear drive passenger car.

This paper describes development of a numerical simulation method for the FMVSS 201 testing. This method considers not only deformation but also fracture of plastic materials. a simplified calculation method for predicting the load during impact of absorbing plastic materials was introduced from the numerical simulation results. By applying this simplified calculator method trial and error in development would be reduced.

Plugin hybrid electric vehicles (PHEVs) have several attractive features in terms of reduction of greenhouse gas (GHG) emissions. Compared to conventional vehicles (CVs) that only have an internal combustion engine (ICE), PHEVs have better energy efficiency like regular hybrids (HEVs), allow for electrifying an appreciable portion of traveled miles, and have no range anxiety issues like battery-only electric vehicles (BEVs). However, in terms of criteria emissions (e.g., NOx, NMOG, HC), it is unclear if PHEVs are any better than HEVs or CVs. Unlike GHG emissions, criteria emissions are not continuously emitted in proportional quantities to fossil fuel consumption. Rather, the amount and type of criteria emissions is a rather complex function of many factors, including type of fuel, ICE temperature, speed and torque, catalyst temperature, as well as the ICE controls (e.g., fuel-to-air ratio, valve and ignition timing).

The demand for thermal comfort in the passenger vehicle compartment is infinite. As a result, technologically sophisticated options and features continue to be upgraded both in the hardware and software sectors. The personalization of comfort became a priority and led to improvements in automatic room temperature control techniques. Furthermore, the demand is rising not only for thermal comfort but also for cabin air quality improvement. Also, contributions to improve mileage and fuel consumption are a new request at the present time. This paper introduces the latest thermal comfort technologies in temperature and airflow controls as well as air quality improvement features. In addition, this paper introduces fuel consumption reduction technology employed by the A/C configuration of the TOYOTA HYBRID SYSTEM.

Traffic accidents in the United States were analyzed using FARS and NASS data. When classified according to vehicle body type and collision type, fatalities were most common in the case of (1) passenger car to passenger car frontal impacts, (2) passenger car to passenger car side impacts, (3) passenger car to LTV side impacts, (4) passenger car to truck frontal impacts, and (5) passenger car to LTV frontal impacts. Among these collisions, it was clearly confirmed that the occupants of a passenger car have a strong tendency to suffer injury when “the passenger car has a frontal impact with a heavier passenger car,” “the passenger car has a frontal impact with an LTV/SUV, truck,” and “the passenger car is side impacted by an LTV/SUV,” or the like. These examples should be recognized as clear cases of incompatibility. This paper will describe an approach which aim at improving compatibility. However, around 60% of occupants who suffer fatal injuries are not wearing a seat belt.

A computational and experimental study has been carried out to assess the high load efficiency and emissions potential of a combustion system designed to operate on low octane gasoline (or naphtha). The “naphtha engine” concept utilizes spark ignition at low load, HCCI at intermediate load, and compression ignition at high load; this paper focuses on high load (compression ignition) operation. Experiments were carried out in a single cylinder diesel engine with compression ratio of 16 and a common rail injector/fuel delivery system. Three fuels were examined: a light naphtha (RON∼59, CN∼34), heavy naphtha (RON∼66, CN∼31), and heavy naphtha additized with cetane improver (CN∼40). With single fuel injection near top dead center (TDC) (diesel-like combustion), excessive combustion noise is generated as the load increases. This noise limits the maximum power, in agreement with the CFD predictions. The noise-limited maximum power increases somewhat with the use of single pilot injection.

It is important for vehicle concept planning to estimate fuel economy and the influence of vehicle vibration using virtual engine specifications and a virtual vehicle frame. In our former study, we showed the 1D physical power plant model with electrical starter, battery that can predict combustion transient torque, combustion heat energy and fuel efficiency. The simulation result agreed with measured data. For idling stop system, the noise and vibration during start up is important factor for salability of the vehicle. In this paper, as an application of the 1D physical power plant model (engine model), we will show the result of analysis that is starter shaft resonance and the effect on the engine mount vibration of restarting from idle stop. First, an engine model for 3.5L 6cyl NA engine was developed by energy-based model using VHDL-AMS. Here, VHDL-AMS is modeling language registered in IEC international standard (IEC61691-6) to realize multi physics on 1D simulation.

Approximately 20% of traffic fatalities in United States 2012 were caused by rollover accidents. Mostly injured parts were head, chest, backbone and arms. In order to clarify the injury mechanism of rollover accidents, kinematics of six kinds of Anthropomorphic Test Devices (ATD) and Post Mortem Human Subjects (PMHS) in the rolling compartment, whose body size is 50th percentile male (AM50), were researched by Zhang et al.(2014) using rollover buck testing system. It was clarified from the research that flexibility of the backbone and thoracic vertebra affected to occupant’s kinematics. On the other hand, the kinematics research of body size except AM50 will be needed in order to decrease traffic fatalities. There were few reports about the researches of occupant kinematics using FE models of body sizes except AM50.

Behavior of sprays formed by slit nozzle as well as swirl nozzles with the spray cone angle in the range of 40° ∼110 ° were studied in a constant volume N2 gas chamber. The fuels used are iso-pentane, n-heptane, benzene and gasoline. The ambient pressure and temperature were raised up to 1.0 MPa and 465 K, respectively. The injection pressure was mainly set at 8 MPa. Spray penetrates at an almost constant speed for a while after injection start and begins to decelerate at a certain point. This point was judged as breakup point, based on a momentum theory on spray motion, the observation of spray inside and the analysis of the spray front reacceleration which occurs under highly volatile condition.

In recent years, the slip lock-up mechanism has been adopted widely, because of its fuel efficiency and its ability to improve NVH. This necessitates that the automatic transmission fluid (ATF) used in automatic transmissions with slip lock-up clutches requires anti-shudder performance characteristics. The test methods used to evaluate the anti-shudder performance of an ATF can be classified roughly into two types. One is specified to measure whether a μ-V slope of the ATF is positive or negative, the other is the evaluation of the shudder occurrence in the practical vehicle. The former are μ-V property tests from MERCON® V, ATF+4®, and JASO M349-98, the latter is the vehicle test from DEXRON®-III. Additionally, in the evaluation of the μ-V property, there are two tests using the modified SAE No.2 friction machine and the modified low velocity friction apparatus (LVFA).

Driveshafts are composed of a transmission side joint, wheel side joint, and shaft which connect the two joints. The Rzeppa type constant velocity joint (CVJ) is usually selected as the wheel side joint of a drive shaft for front wheel drive automobiles. Due to recent needs of fuel efficiency and lighter weight for vehicles, it is necessary to reduce the joint size and improve the efficiency of a CVJ. In order to reduce the weight, solving tribology details for long life under high contact pressure is an important issue for developing a CVJ. It is difficult to understand the characteristics of a contact surface, such as relative slip velocity or spin behavior, because the outer race, inner race, cage, and balls, act complicatedly and exchange loads at many points. Meanwhile, after joint endurance tests, ball spalling marks at pole of the ball are sometimes observed.