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A new blow molding process has been developed which yields Class “A” paintable surfaces on BEXLOY® exterior body panels directly out of the mold. The process is the result of three years of research and involves a thermocycling technique which maintains the surface of the part at a temperature above the plastic flow point. This enables the material to exactly replicate the mold surface thus eliminating surface defects such as die lines, pits, and waviness. This technology offers reduced finishing costs and greater design freedom for the use of BEXLOY Thermoplastic Resins in large Class “A” exterior body panels.

This paper presents the methodology of the investigative techniques for examining vehicular fires. Discussion illustrating the mechanical “finger prints” that show the investigating team the mechanism of fire spread is presented. The common causes of vehicular fires and examples of each are discussed. The techniques used by the forensic chemist in determining incendiary fires and the use of specialized equipment in the investigation are illustrated. Tests are discussed to show the theories postulated in the investigative stages of the vehicle examination. Lastly, the interdisciplinary team approach to the investigation is discussed showing the validity of “forensic” engineering and chemistry in examining vehicle fires.

There have been documented cases of rollover accidents wherein the driver was ejected while wearing the single loop lap/shoulder harness. Three actual incidents will be discussed here. In two of the three cases the vehicle was photographed at the accident scene with the latchplate still in the buckle, whereas in the other case, the evidence of the seatbelt having been latched was found some time after the accident. Rollover accidents are second to frontal collisions in severe injury causation. It is an accepted fact that retention in the vehicle is necessary for an occupant to have a chance at mitigating the injuries associated with a rollover event. It is also the purpose of the seatbelts to restrain the occupant and prevent ejection in this kind of vehicle accident. In this paper, the design of the seatbelt retractor will be analyzed to determine its role in the retention of occupants in a rollover collision.

The purpose of this study is to attempt to quantify the differences between CRASH3 generated velocity change (ΔV) as used in the National Automotive Sampling System - Crashworthiness Data System (NASS-CDS) and measured velocities in actual frontal crash tests. An appropriate factor is then applied to ΔV in NASS to estimate an adjusted ΔV distribution based on these differences. A substantial change to the velocity distribution in NASS-CDS will have a significant bearing on the estimates of lives and injuries affected by any changes to the impact velocity for the frontal crash test in FMVSS No. 208 or other rulemaking decisions.

Magnesium die casting alloys have the mechanical properties of metals, yet are lightweight like plastics and offer the designer a wide variety of applications. Plastics have previously been considered the most cost effective material for components that have limited mechanical requirements. Also, plastics' past history of being lightweight and easy to manufacture has made them attractive. However, in many instances, using magnesium instead of plastics offers a less expensive part that is much stronger, stiffer, just as lightweight and often easier to manufacture.

In several European countries, unprotected road users form a significant proportion of road accident casualties. The Research Institute for Road Vehicles TNO has started a long-term research program on pedestrian and cyclist safety. Up to now, 38 full-scale dummy tests with simulated vehicle fronts and real passenger cars were performed. Furthermore, 3D mathematical model simulations were conducted with the MADYMO Crash Victim Simulation (CVS) package. A part of the program is presented in this paper. The influence of vehicle geometry and speed on pedestrian and cyclist kinematics in a lateral impact is shown, as well as the influence of bicycle mass and speed. The results of cyclist and pedestrian tests will be compared with each other.

Aeration rate in engine oil is one of the most important data in developing lubrication system of the internal combustion engine. Several methods were reported to measure oil aeration, but none of them can measure aeration rate in real time at in-vehicle tests. The present study developed oil aeration meter that is able to measure oil aeration in real time without sampling oil out of engine. And the meter is very compact in size and the response time of the meter is fast enough, thus the meter can be applied to in-vehicle tests. The meter measures density, pressure and temperature of the air-oil mixture, and those variables are measured with high precision, thus the oil aeration meter having uncertainty less than 1% could be developed. The oil aeration meter is successfully being applied to develop the lubrication system of engine.

The majority of all highway-type vehicle (cars, trucks, vans, buses, camping trailers, etc.) fire deaths result from fires caused by collisions or overturns. However, more than one third of these deaths resulted from fires that did not follow a collision or overturn. Compared to vehicle fire deaths from collisions or overturns, vehicle fire deaths resulting from non-collision, non-overturn fires are less likely to occur on highways or road properties, more likely to originate in the passenger area and more likely to have victims who are under 5 years of age or 65 or older.

The National Automotive Sampling System (NASS) Crashworthiness Data System (CDS) contains a wealth of field accident data. As the size of the database continues to grow, the statistical significance of the data increases and trends can be observed. Numerous papers contain analysis and graphs of particular aspects of the data, but they are usually included in a supporting role to the main topic of the paper, and are extremely difficult to locate in a focused document search. The purpose of this paper is to provide an updated, comprehensive resource to reference when looking for commonly sought-after accident statistics. Charts include accident distributions by Delta-V and impact direction with corresponding injury severity rates. Rollover data is also analyzed, as well as historical trends for injury severity, belt usage, and air bag availability.

Virtual prototyping has been widely used in the industry and academy as a system performance prediction tool before production. Particularly for the analysis of vehicle ride comfort, the quarter car model is popular since it requires only the essential and least amount of input data. However, the assumption of point contact between the tire and road may sometimes be misleading, especially in rough road applications or low pressure tires for all terrain vehicles (ATV). To have a realistic prediction at the early design stage when little information is available, the quarter car model is modified in this research by allowing the tire to leave off the ground and considering variable tire patch contact. These features are important when designing ATVs used in versatile environments and with low pressure tires. Inclination of distributed tire springs and constant division road profile are implemented to facilitate fidelity and efficiency in simulation.

Rollover crashes have continued to be a source of extensive research into determining both vehicle performance, and occupant restraint capabilities. Prior research has utilized various test procedures, including the FMVSS 208 dolly fixture, as a basis for evaluating vehicle and restraint performance. This research, using 2001 Nissan Pathfinder sport utility vehicles (SUVs), was conducted to update the status of passenger vehicle rollover testing, and evaluate dynamic test repeatability with a new test procedure. A series of eight rollover tests was conducted using these SUV vehicles, mounted on a modified FMVSS 208 rollover dolly fixture, with instrumented dummies in both front seat positions. This test protocol involved launching the vehicles horizontally, after snubbing the dolly fixture, and having the leading-side tires contact curbing for a trip mechanism.

The evaluation of a rollover accident requires the assessment of a large amount of information in order to completely analyze the accident and determine the vehicle dynamics throughout its roll sequence. This information includes the physical evidence available through examination of the accident site, the vehicle and any photographs or documentation of the accident scene. Many times there is a lack of scene data available complicating a thorough evaluation of the vehicle path and roll distance during the rollover. Inspection of the vehicle reveals the minimum number of rolls the vehicle experienced during the rollover event, leaving the roll distance traveled as one of the many unknown variables. This paper compares the roll distance, roll speed and number of rolls for dolly testing and real world rollovers. An evaluation of the roll distance and number of rolls for passenger cars, light trucks and sport utility vehicles is compiled and compared to one another.

The primary description of crash severity in most accident databases is vehicle delta-V. Delta-V has been traditionally estimated through accident reconstruction techniques using computer codes, e.g. Crash3 and WinSmash. Unfortunately, delta-V is notoriously difficult to estimate in many types of collisions including sideswipes, collisions with narrow objects, angled side impacts, and rollovers. Indeed, approximately 40% of all delta-V estimates for inspected vehicles in the National Automotive Sampling System / Crashworthiness Data System (NASS/CDS) 2001 are reported as unknown. The Event Data Recorders (EDRs), now being installed as standard equipment by several automakers, have the potential to provide an independent measurement of crash severity which avoids many of the difficulties of accident reconstruction techniques. This paper evaluates the feasibility of replacing delta-V estimates from accident reconstruction with the delta-V recorded by EDRs.

Trajectories of ice shed from two variants of a business jet were computed to show that a change in fuselage length did not increase the risk of ice ingestion by the engine. A droplet trajectory code modified for solid ice shapes, was used in the analysis. This method could help reduce icing flight tests when minor modifications are made to an aircraft.

The optimization of aerodynamic drag represents an important research area for the fuel consumption reduction of heavy duty commercial vehicles. Today's design of tractor-trailers is significantly influenced by legal conditions regarding the vehicle dimensions and the provision of a maximum transportation volume. These boundary conditions lead to brick-shaped trailer outer geometries, especially at the rear ends. That is the reason why the investigations of aerodynamic optimization of commercial vehicle trailers are predominantly restricted to detail measures up to now. The present publication treats the aerodynamic characteristics of general modifications on the outer contour of long-distance haulage trailers in regard of reducing the drag resistance and, thus, potentially also the fuel consumption in highway traffic. A new approach for the realization of a variable outer contour of trailers provides the possibility to adjust the rear end to an aerodynamically optimized shape.

Rotational motion of the head as a mechanism for brain injury was proposed back in the 1940s. Since then a multitude of research studies by various institutions were conducted to confirm/reject this hypothesis. Most of the studies were conducted on animals and concluded that rotational kinematics experienced by the animal's head may cause axonal deformations large enough to induce their functional deficit. Other studies utilized physical and mathematical models of human and animal heads to derive brain injury criteria based on deformation/pressure histories computed from their models.

Head trauma continues to be the most frequent cause of life threatening injury to racing drivers and protecting the driver's head is of prime importance. A head protection system must ensure that any loads or accelerations imparted to the head do not exceed those which may cause injury. The FIA commissioned the Transport Research Laboratory (TRL) in the UK to develop an advanced protective helmet and to propose an improved standard to which Formula-One protective helmets must comply. Throughout the project, TRL worked closely with the FIA Research Group, Carbon Fibre Technologies-UK, Bell Sports Europe and Snell-USA. During a preliminary phase, the performance of current motorsport helmets was evaluated with regard to both laboratory test and simulated accident conditions. Based on this work, provisional performance criteria were agreed for the improved helmet design.

This paper introduces vehicle test method, data processing and result parameters of an objective evaluation method to quantify on-center handling at freeway driving. Vehicle test is conducted on a flat straight road with a low frequency sinusoidal steering angle input. The result consists of eleven parameters that describe relations of two quantities such as gain, non-linearity and lag time.

Door Closing Effort is one of the first impressions a potential customer has about a vehicle. The energy someone needs to give out to push and lock a side door vehicle is easily felt and can enhance the impression of a robust and high quality design vehicle. In other words, Door Closing Effort is one of the issues manufacturers shall look over in order to achieve perfect levels of Human Vehicle Integration (HVI). The aim of this paper is to present a case study of Side Door Closing Effort of a specific Hummer vehicle. It will be shown how door closing effort varies according to several parameters, and how to improve the design and/or production process in view of achieving better effort levels, considering the Hummer case as a background. Several variables that influence on the overall energy of this process have been evaluated, and the physical differences were weighted to demonstrate what really counts for reaching a comfortable level of Door Closing Effort.

Permanent magnet synchronous motors (PMSM) are widely used in the electric vehicles for their high power density and high energy efficiency. And the motor control system for electric vehicles is one of the most critical safety related systems in electric vehicles, because potential failures of this system can lead to serious harm to humans’ body, so normally a high automotive safety integrity level (ASIL) will be assigned to this system. In this paper, an ASIL-C motor control system based on a multicore microcontroller is presented. At the same time, due to the increasing number of connectivity on the vehicle, secure onboard communication conformed to the AUTOSAR standard is also implemented in the system to prevent external attacks.