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This paper has utilized a specially created subset of the data contained within the National Accident Sampling Study (NASS) for an updated and expanded analysis of the relationship between Delta V and injury. The data presented embrace over 20,000 accidents of passenger cars, light trucks and utility vehicles involved in accidents between 1980 and 1991. These unique accidents have been extracted from the massive amount of available information contained within the NASS data in order that the variables which have the greatest information content for our subject can be studied and analyzed. Some of the variables which were extracted and studied include Delta V, Principle Direction of Force, restraint system type and use, injuries, vehicle weight and type as well as the occupant variables of age and sex which are believed to influence human tolerance to injury.

The relationship between thermal stability of gasoline additives and their effect on engine combustion chamber deposits (CCDs) has been explored using a wide range of candidate gasoline additive chemistries. Although a weak correlation may be observed between thermal stability and total CCDs, the data scatter is far too great to permit the relative CCD performance of additives to be predicted from thermogravimetric analysis (TGA) properties alone. It is concluded that TGA alone is too simple a measure to reflect the true complexity of deposit formation in a combustion chamber and that correlations with CCDs degrade further when TGAs are determined from UWG samples extracted from additivated gasolines.

A fired multi-cylinder laboratory dynamometer engine test has been developed for measuring the effect of engine oil on fuel consumption with high statistical confidence. The range of test conditions employed encompasses both the hydrodynamic and boundary lubrication regimes so that frictional, as well as viscometric effects can be detected. The effects of viscosity and SAE viscosity grade for Newtonian and non-Newtonian test lubricants, and the effect of viscosity index improver molecular weight within an SAE grade have been studied. The results obtained are largely explained by the rheological properties of the test fluids. The relationship between the performance of non-Newtonian and Newtonian oils has been found to be dependent on engine type, presumably due to engineering characteristics which affect the shear stresses and temperatures imposed upon the lubricant.

The objective of the work was to conduct a parametric study using the major combustion system variables to investigate the parameters controlling the nitric oxide and fuel economy trade-off, identify the major basic in-cylinder physical processes responsible, and relate these processes to the hardware features. The study was conducted using a multizone, fuel and air jet mixing model with a temperature and concentration dependent fuel reaction rate, and nitric oxide kinetics. The effect of engine variables on the relationship between nitric oxide emissions and work during the valve closed part of the engine cycle was studied by systematically changing twelve engine variables. Selected parameter variations were also repeated experimentally using a single cylinder engine.

In the past there has been much data presented indicating a shift toward increasing the small car population would adversely affect occupants. Obviously in an unequal two-vehicle collision, the small car is at a disadvantage. In the available data presented relative to two-vehicle collisions only, however, the unadjusted fatality rates show that a small car is much safer than a large car. Although this result is obtained because of the preponderance of young people in small cars, ever after adjusting the results to account for expected age distribution of the driving population the small-small collision is slightly less severe than the large-large collision. Small cars, in this study, are cars weighing less than 3500 lb. This analysis shows optimism for the future, and it appears that occupants are at an advantage if involved in two-vehicle collisions while in small cars.

The paper describes the use of Road octane number equations to predict the antiknock performance of motor gasoline under a wide variety of operating conditions. It then goes on to describe how reference fuels can be used to determine the octane requirement of engines in terms of Research octane number, Motor octane number and front-end quality and how the information can be used to calculate what proportion of any given market will be satisfied by gasolines of known inspection properties. Brief mention is also made of the relationship between calculated values of car satisfaction and observed levels of customer satisfaction and the effects of lead, aromatics and olefins on road antiknock performance. Future octane quality is discussed and the need for close co-operation between the oil industry, the motor industry and the legislators is identified.

This paper summarizes the published information on the relationship between oil viscosity and engine performance that may be of use in developing a new engine oil viscosity classification system. The specific engine performance factors and associated variables considered are wear, oil consumption, fuel economy, hot starting, cold starting, low temperature pumpability, noise, and shear stability.

The friction performance and thermal resistance of paper-based wet friction materials used for automotive automatic transmissions are influenced by the material structure formed as a result of the combination of porosity and resiliency. In our previous papers, the effects of porosity on the frictional performance and the thermal resistance were characterized by Stribeck Diagrams based on continuous sliding test data, and were also discussed with reference to torque curves and temperature measurements by an SAE No. 2 friction tester. In this paper, the effects of porosity on the mechanical strength and the fatigue of paper-based friction materials were studied for practical paper-based materials. The mechanical strength like shear strength, etc. of the material tends to decrease as the porosity increases. The fatigue life of the material, when the repeated compression and shear force are applied at the same time, was also discussed.

Measurement using a three-dimensional anemometric-tester was made for the gas flow inside the cylinder of a two-stroke engine while the shape of the transfer port was modified. The relationship between port shape and engine performance was investigated for various factors that characterize the flow in cylinder. In this paper, we focused mainly on two engine running conditions: the maximum output at 11750 rpm and the output at 10000 rpm. As a result, we found that the maximum output is most related to the tangential inclination angles of the main transfer port, and the inner vent radius of the main transfer duct.

This paper discusses the primary roles of product planners and product designers with the intent of demonstrating their differences and inter-relationships in the design process. Descriptions of planning and design functions are followed by illustrations of the major points of inter-action between the two groups. Emphasis is placed on the complimentary contributions each makes to the process.

With rising customer expectations, driver comfort will become more and more important for car manufacturers in distinguishing themselves from others. This is a challenge, since it is difficult to predict comfort, especially in early design stages. Today, comfort can only be assessed and tested very late in the design a construction process (often using prototypes). Potentially, biomechanic software solutions provide a solution for early comfort testing. Hence, the application of this solution will decrease cost and development time. However, before one is able to create such a software solution, one must have insight into the relationship between mechanical parameters and comfort. This relationship was investigated through a series of experiments in a driving simulator. Both mechanical parameters and comfort were measured. The results showed that seat pressure measurements can be used to quantify driver comfort.

Tire mark striations are discussed often in the literature pertaining to accident reconstruction. The discussions in the literature contain many consistencies, but also contain disagreements. In this article, the literature is first summarized, and then the differences in the mechanism in which striations are deposited and interpretation of this evidence are explored. In previous work, it was demonstrated that the specific characteristics of tire mark striations offer a glimpse into the steering and driving actions of the driver. An equation was developed that relates longitudinal tire slip (braking) to the angle of tire mark striations [1]. The longitudinal slip equation was derived from the classic equation for tire slip and also geometrically. In this study, the equation for longitudinal slip is re-derived from equations that model tire forces.

The paper investigates and proves that measurement of the near field sound and sidewall vibration are comparable to the tire far field noise and thus may be used to reasonably evaluate tire noise characteristics. Other conclusions of the research include: Any two of the three quantities of A-weighted sidewall acceleration near field sound, and peak pass-by sound may be related by a constant for a given road surface and that vibration normal to the surface of the tire is coherent with the tire near field sound.

Rollover accidents account for a large number of serious to fatal injuries annually. In the past, these injuries were often the result of unrestrained occupant ejection. Subsequent to mandatory belt use laws, a larger percentage of these injuries occur inside the vehicle, and the head and neck areas sustain a substantial number of these injuries. Rollovers have been characterized as violent events, roof crush as the natural consequence of such violence. Further, head and neck injury have been thus considered unavoidable, even with occupant use of the production restraints. This paper will describe the relationship between the three dimensional extent (severity) of roof crush and the equivalent drop test contact velocity as derived from physical experiments and tests. The drop test contact velocity is directly related to the cumulative change of velocity experienced by a vehicle as a result of roof contact deformation during a rollover accident by validated computer simulations.

Linear analysis and corresponding vehicle tests have been used since the late 1950's to help understand the directional response of automobiles and commercial vehicles. This work is now well accepted, and linear terms such as understeer gradient and response time are descriptors routinely used to characterize vehicle performance in the linear range. This paper assesses the use of various levels of complexity in linear models. It verifies that, for steady state measures such as understeer gradient, all important effects can be handled quasistatically and a two degree of freedom model is adequate. The paper then illustrates situations in which the roll degree of freedom can be important for transient calculations, and assesses the changes in calculated transient results deriving from the addition to the model of time lags in lateral tire force buildup.

DISPARITY between the factors of automobile and highway design that are far advanced and the factors that lag far behind constitutes the cause of many of our transportation difficulties, according to the author. The paper therefore aims to show the demand for safety and its economic advantage to the automotive industry and to indicate some of the principles necessary for its accomplishment. After stating that the automobile manufacturers should take a far-sighted view of the situation, take positive steps toward safety and cash in on the demand that is growing and that cannot be stopped by denying its existence, the author considers and comments upon some of the characteristics of automobiles that undoubtedly are partly responsible for accident potentialities. Visibility from the driver's seat is considered in detail, together with devices that assist visibility. The other driver's viewpoint also is considered.