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This paper reports on the injuries to the head, neck and thorax of fifteen child surrogates, subjected to varying levels of sudden acceleration. Measured response data in the child surrogate tests and in matched tests with a three-year-old child test dummy are compared to the observed child surrogates injury levels to develop preliminary tolerance data for the child surrogate. The data are compared with already published data in the literature.

Available methodologies for model bias identification are mainly regression-based approaches, such as Gaussian process, Bayesian inference-based models and so on. Accuracy and efficiency of these methodologies may degrade for characterizing the model bias when more system inputs are considered in the prediction model due to the curse of dimensionality for regression-based approaches. This paper proposes a copula-based approach for model bias identification without suffering the curse of dimensionality. The main idea is to build general statistical relationships between the model bias and the model prediction including all system inputs using copulas so that possible model bias distributions can be effectively identified at any new design configurations of the system. Two engineering case studies whose dimensionalities range from medium to high will be employed to demonstrate the effectiveness of the copula-based approach.

This paper reports the analytical procedure developed for a simulation of knee impact during a barrier crash using a hybrid III dummy lower torso. A finite element model of the instrument panel was generated. The dummy was seated in mid-seat position and was imparted an initial velocity so that the knee velocity at impact corresponded to the secondary impact velocity during a barrier crash. The procedure provided a reasonably accurate simulation of the dummy kinematics. This simulation can be used for understanding the knee bolster energy management system. The methodology developed has been used to simulate impact on knee for an occupant belted or unbelted in a frontal crash. The influence of the vehicle interior on both the dummy kinematics and the impact locations was incorporated into the model. No assumptions have been made for the knee impact locations, eliminating the need to assume knee velocity vectors.

A flow network method was developed to predict the underhood temperature distribution of an automobile. The method involves the solution of simplified energy and momentum equations of the air flow in control volumes defined by subdividing the air space between the surfaces of the underhood components and the front-end geometry. The control volumes are interconnected by ducts with branches and bends to form a flow network. Conservation of mass and momentum with appropriate pressure-loss coefficients leads to a system of algebraic equations to be solved for the flow rates through each volume. The computed flow rates are transferred to a thermal model to calculate the temperatures of the air and the major vehicle components that affect the underhood environment. The method was applied to a 1986 3.0L Taurus and compared with vehicle experiments conducted in a windtunnel.

There have been many articles published in the last decade or so concerning the components of an electronic stability control (ESC) system, as well as numerous statistical studies that attempt to predict the effectiveness of such systems relative to crash involvement. The literature however is free from papers that discuss how engineers might develop such systems in order to achieve desired steering, handling, and stability performance. This task is complicated by the fact that stability control systems are very complex and their designs and what they can do have changed considerably over the years. These systems also differ from manufacturer to manufacturer and from vehicle to vehicle in a given maker of automobiles. In terms of ESC hardware, differences can include all the components as well as the addition or absence of roll rate sensors or active steering gears to name a few.

European legislation covering noise, smoke emission and industrial pollution, all seeking to improve the environment are not addressed in this paper, which takes only exhaust emission and fuel complexity as its subjects. It describes how this complexity can inhibit the development capacity, thus restricting the model offering of a major european automobile manufacturer. The paper concludes that general benefit would be derived from genuine pan european emission legislation, particularly if that legislation was established at levels of control that allowed the development and use of modern engine technology.

The pumping system used in a step ratio automatic transmission can consume up to 20% of the total power required to operate a typical automotive transmission through the EPA city cycle. As such, it represents an area manufacturers have focused their efforts towards in their quest to obtain improved transmission efficiency. This paper will discuss the history of automatic transmission pumps that develop up to 300 psi along with a description of the factors used to size pumps and establish pump flow requirements. The various types of pumps used in current automatic transmissions will be described with a discussion of their characteristics including a comparison based upon observations of their performance. Specific attention will be focused on comparing the volumetric efficiency, mechanical efficiency, overall efficiency, pumping torque and discharge flow.

This paper describes a comprehensive methodology for the simulation of vehicle body panel buckling in an electrophoretic coat (electro-coat or e-coat) and/or paint oven environment. The simulation couples computational heat transfer analysis and structural analysis. Heat transfer analysis is used to predict temperature distribution throughout a vehicle body in curing ovens. The vehicle body temperature profile from the heat transfer analysis is applied as an input for a structural analysis to predict buckling. This study is focused on the radiant section of the curing ovens. The radiant section of the oven has the largest temperature gradients within the body structure. This methodology couples a fully transient thermal analysis to simulate the structure through the electro-coat and paint curing environments with a structural, buckling analysis.

Model characteristics of a finite element deformable featureless headform with one to four layers of solid elements for the headform skin are studied using both the LS-DYNA3D and FCRASH codes. The models use a viscoelastic material law whose constitutive parameters are established through comparisons of drop test simulations at various impact velocities with the test data. Results indicate that the one-layer model has a significant distinct characteristic from the other (2-to-4-layer) models, thus requiring different parametric values. Similar observation is also noticed in simulating drop tests with one and two layers of solid elements for the headform skin using PAM-CRASH. When using the same parametric values for the viscoelastic material, both the LS-DYNA3D and FCRASH simulations yield the same results under identical impact conditions and, thereby, exhibit a “functional equivalency” between these two codes.

A number of advancements have been made in the coulometric sulfur trace instrumental technique for the real-time measurement of engine oil economy. These advancements include modification of the coulometric cell to improve reliability and reproducibility. The instrument has been interfaced with a microcomputer for instrument control as well as data acquisition, storage, and analysis. Studies were undertaken which demonstrate sufficient sensitivity and linearity for determination of engine oil economy at levels better than 10,000 miles/quart. Applications to steady-state engine oil consumption mapping and to instantaneous oil consumption during transient engine cycling are described. These instruments are being produced by an outside supplier for use in various company locations in both the engine production and engine research environments.

The long term visual appearance of exterior chrome-plated parts is highly dependent on part design and supplier performance. The use of numerous complex designs coupled with the pressures of competition has caused a statistically high percentage of parts to be manufactured which do not fully meet customer expectations. A coordinated approach to improve supplier performance and simplification of part designs was required. A task force was established to address these issues in 1980 and desirable results were achieved.

The SAE Large Male and Small Female Dummy Task Group has recommended a change to the Hybrid III dummy hip joint. This change was made because of a non-biofidelic interference in the current design that can influence chest accelerations. The modifications include a new femur casting shaft design and the addition of an elastomeric stop to the top of the casting. Static testing and Hyge sled tests were done to evaluate the modifications. Based on the results, the new design satisfied the requirements set by the SAE task group and reduced the influence of hip joint characteristics on chest accelerations.

In this paper, we present the results of a series of experiments to determine the exhaust particulate size distributions from a number of diesel, gasoline and compressed natural gas (CNG) fuelled vehicles. The results show that all three types of vehicle produce significant populations of particulates under certain operating conditions. Particulates produced by gasoline and CNG engines tend to be smaller than for diesel engines. At low loads, there is a significant particulate distribution for diesel engines but much lower particulate numbers for both gasoline and CNG vehicles. Under these conditions, the gasoline particulate distribution has little structure but the CNG distribution is clearly bimodal. At higher loads, the number of particulates produced by diesel vehicles increases by an order of magnitude from idle and both the CNG and gasoline distributions are comparable in peak height. The diesel vehicle produces a much larger particulate volume than gasoline or CNG.

For many years, carmakers have developed unique system designs to gain a competitive advantage using some unique technology or an optimization of a design to cut costs or improve quality. This leads to continual increase in complexity, long development times and high development costs. A common platform, based on an "open architecture,'' provides a solution for many of the problems associated with the conventional automotive approach to electrical/electronic system designs. The PC industry is a prime example of how an open architecture can provide benefits to the consumer, manufacturers of software and hardware components, as well as complete system integrators. The PC, based on the initial IBM computer developed in the early eighties, has become a de facto standard that has survived 20 years of fast and dramatic changes in the fundamental technologies used within the platform.

This paper discusses steps for identifying, evaluating and recommending a quantifiable design metric or metrics for Side Airbag (SAB) development. Three functionally related and desirable attributes of a SAB are assumed at the onset, namely, effective SAB coverage, load distribution and efficient energy management at a controlled force level. The third attribute however contradicts the “banana shaped” force-displacement response that characterizes the ineffective energy management reality of most production SAB. In this study, an estimated ATD to SAB interaction energy is used to size and recommend desired force-deformation characteristic of a robust energy management SAB. The study was conducted in the following three phases and corresponding objectives: Phase 1 is a SAB assessment metric identification and estimation, using a uniform block attached to a horizontal impact machine.

While testing vehicles for crash, particularly the offset frontal crash mode, new devices and techniques are needed to enhance the ability to measure rotations of certain vehicle components and dummy parts (or joints). The reason for this new demand is that the capabilities of existing techniques or devices in measuring rotations of small masses in confined areas are limited. Examples of the desired measurements are the rotations of dummy's feet and tibias as well as the rotations of the vehicle's toe-board during intrusion. These measurements help to understand dummy's ankle loads as a result of different intrusion rates. Furthermore, having these measurements is very beneficial to the validation of the computer models used in simulating the behavior of dummy's lower extremities in high intrusion crashes. Recent research demonstrated the use of an angular rate sensor, based on magnetohydrodynamic principles, on Hybrid-III dummies and cadavers.

The purpose of this paper is to describe the growth and the trends of automotive convenience products. These products contributed to make the driving experience more pleasurable. Electronics have contributed to this growth since the sixties, and its contribution and prospects will be the prime focus of this paper. With the continuing advance of electronic products in the consumer and industrial sectors, the consumer wants' and expectations are changing, especially with the “Baby Boom” generation. More new convenience features will be developed by the prudent use of electronics. The development of these future products require a thorough understanding of consumer wants and needs through market research, careful adaptation of the emerging technology to avoid gimmickry, and dedicated application of engineering know how to design package efficient, cost effective and reliable products.

The increasing importance of safety performance in all aspects of motor vehicle design, development, manufacture and marketing makes it necessary for professionals working in these areas to be more aware of safety considerations. The background material and concepts presented in this book will be useful as a basis to aid in the understanding of future developments in this fascinating area.

Automotive vehicle body electrophoretic (e-coat) and paint application has a high degree of complexity and expense in vehicle assembly. These steps involve coating and painting the vehicle body. Each step has multiple coatings and a curing process of the body in an oven. Two types of heating methods, radiation and convection, are used in the ovens to cure coatings and paints during the process. During heating stage in the oven, the vehicle body has large thermal stresses due to thermal expansion. These stresses may cause permanent deformation and weld/joint failure. Body panel deformation and joint failure can be predicted by using structural analysis with component surface temperature distribution. The prediction will avoid late and costly changes to the vehicle design. The temperature profiles on the vehicle components are the key boundary conditions used to perform structure analysis.

This paper describes the development and key features of a bar code based, computerized gas cylinder inventory and record keeping system developed by Ford Motor Company's Gas Standards Laboratory. The paper will demonstrate how bar code technology is being utilized to track compressed gas cylinders efficiently and accurately. It will also describe the link between bar code technology and a data base that was developed using a fourth generation computer language. The implementation of this bar code/data base system has significantly increased data accessibility, improved data quality, reduced training time and increased the efficiency and flexibility of the data reporting process.