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This paper presents our efforts to formalize the knowledge domain of nondestructive quality control of automotive composite components with organic (resin) matrices and to develop a prototype knowledge-based system, called NICC for Nondestructive Inspection of Composite Components, to help in the quality assurance of individual components. Geometric and bonding characteristics of parts and assemblies are taken into account, as opposed to the better understood evaluation of test specimens. The reasoning process was divided in two stages: in the first stage all flaws that might be present in the given part are characterized; in the second stage appropriate nondestructive testing procedures are specified to detect each of the possible flaws. The use of nondestructive techniques in the inspection of composites is fairly recent and hence, the knowledge required to develop an expert system is still very scattered and not fully covered in the literature.

The pulleys employed in automotive accessory drive systems very often consist of a two piece assembly; a multitude of fastening techniques are used in completing the assembly. There are numerous assembly methods and a variety of distinct pulley configurations dictated by the various automobile manufacturers in accordance with individual accessory drive needs. An expert system is being developed to evaluate the merit of multiple assembly alternatives for a specific pulley application. The expert system provides a consistent evaluation tool for assembly alternatives, balancing the influence of product cost, strength and quality considerations. The knowledge-based system is implemented in an expert system shell called AGNESS (A Generalized Network-based Expert System Shell). The expert system judges the acceptability of various pulley assembly techniques, assigning a high “merit value” to the better designs and proportionately lower values to less desirable designs.

Since the end of W.W.II, many countries have embarked on various to develop a national automobile industry to spur the economic growth of the country, to meet the rising domestic demand for automobiles, and to compete in the world markets. Can these countries achieve these objectives and at the same time retain their national independence in the automobile industry from the domination of the foreign multinational automobile manufacturers? This paper addresses these questions by examining first, the records of Latin America (Argentina, Brazil, Mexico), South Korea and Taiwan in Asia Pacific Region; it then attempts to determine to what extent their experiences may be transferrable to the Chinese automobile industry which is currently undergoing modernization. For the purpose of this paper, the automobile industry encompasses only passenger vehicles.

Designing trucks for good ride characteristics is a challenge to the engineer, given the many design constraints imposed by requirements for transport productivity and efficiency. The objective of this lecture is to explain why trucks ride as they do, and the basic mechanisms involved. The response of primary interest is the vibration to which the driver is exposed in the cab. Whole-body vibration tolerance curves give an indication of how those vibrations are perceived at the seat; however, ride studies have shown that visual and hand/foot vibrations are also important to the perception of ride in trucks. The ride environment of the truck driver is the product of the applied excitation and the response properties of the truck. The major excitation sources are road roughness, the rotating tire/wheel assemblies, the driveline, and the engine.

This paper summarizes the results of Phase 1, Concept Definition, of the AATD program and identifies the reasons such a new test device is needed. The following areas are addressed: 1) injury priority from accident data; 2) current dummy design, use, and potential improvements; and 3) technical characteristics and design concepts for a new AATD, its data processing, and its certification systems.

A cylindrical combustion bomb with dynamic charging system and electro-hydraulic sampling valve is used to study the effects of turbulence on hydrocarbon (HC) emissions from a quench layer and from artificial crevices. The turbulence level is varied by changing the delay time between induction of combustible charge and ignition. Propane-air mixtures were studied over an initial pressure range of 150 to 500 kPa and equivalence ratios of 0.7 to 1.4. Sampling valve experiments show that quench-layer fuel hydrocarbons are extensively oxidized within 5 ms of flame arrival under laminar conditions and that turbulence further reduces the already low level. Upper limit estimates of the residual wall layer HC concentration show that residual quench layer hydrocarbons are only a small fraction of the exhaust HC emission.

Secondary injection in a diesel engine is defined as the introduction of additional fuel into the combustion chamber after the end of the main injection. It is usually caused by residual pressure waves in the high-pressure pipe line connecting the pump and injector. When these waves exceed the injector opening pressure, secondary injection occurs. Tests revealed that the U.S. Army TACOM single-cylinder engine used in this investigation, fitted with an American Bosch injection system, had secondary injection within the normal engine operating region. The pump spill ports and delivery valve were redesigned to eliminate secondary injection, in accordance with previously reported work. Comparative tests of both the conventional and modified injection systems were run on the same engine, and the effects of secondary injection on engine power, economy, and exhaust emissions were determined.

Lap-shoulder belt effectiveness has been indicated by many authors, however there is minimal information on the more severe injuries to lap-shoulder belted car occupants. This paper presents details of 15 lap-shoulder belted occupants in frontal collisions and 24 lap-shoulder belted occupants in side impact collisions. Case descriptions of these crashes are presented, each including vehicle, environmental and injury details.

Properties of the human neck which may influence a person's susceptibility to “whiplash” injury during lateral impact have been studied in 96 normal subjects. Subjects were chosen on the basis of age, sex, and stature and data were grouped into six primary categories based on sex (F, M) and age (18-24, 35-44, 62-74). The data include: measures of head, neck and body anthropometry in standing and simulated automotive seating positions, three-dimensional range of motion of the head and neck, head/neck response to low-level acceleration, and both stretch reflex time and voluntary isometric muscle force in the lateral direction. Reflex times are found to vary from about 30 to 70 ms with young and middle aged persons having faster times than older persons, and females having faster times than males. Muscle strength decreases with age and males are, on the average, stronger than females.

Although over 800 references to child and infant anthropometry are in the literature, most have limited validity and application to current populations. Functional measures required by industry and government for federal safety standards for design of dummies, child products, furniture, or protective devices such as restraint systems have either been incomplete, inadequate, or nonexistent. Some of the limitations influencing validity of existing data have been outlined for the potential user. As a start toward obtaining necessary functional anthropometric data, The University of Michigan is currently conducting a study sponsored by the U.S. Consumer Product Safety Commission to obtain valid nationwide measurements on a representative U.S. population from birth to age 12 years. In this study some 41 measurements, including many functional measures, as well as seated and supine whole-body centers of gravity, are being taken utilizing a new automated anthropometric minicomputer system.

After-injection is the introduction of additional fuel to the combustion chamber after the end of the main injection. It is a persistent diesel fuel injection problem which usually results in reduced engine power and economy and increased emissions. After-injection is caused by uncontrolled pressure transients at the injector after the opening of the pump spill port. These pressure transients are related to the wave propagation phenomena in the high-pressure pipeline connecting the pump and injector. Use of experimental trial-and-error methods in attempts to control this phenomenon has met with limited success. The analytical control method described in another paper is used to determine design means by which after-injection may be controlled. Further investigation and evaluation of two design changes which release the injection system excess elastic energy in a controlled manner are considered herein. One design change is the addition of a control valve in the pump delivery chamber.

The increasing requirements imposed on diesel engine manufacturers have required the study of fuel injection system faults and the development of means to eliminate them. Until now, improved injection system characteristics have been obtained by experimental trial-and-error procedures. These procedures, however, have proved to be inconvenient, tedious, and have had limited success in eliminating system faults such as after-injection. This is mainly because the transient nature of the injection process requires a more thorough study of the system time-varying parameters. In this paper the residual transients which cause after-injection are analytically investigated. The control of these transients required specification of some system parameter. The rapidly varying nature of the system pressures and flows prevented the use of these variables as control parameters.

Based on a review of existing theoretical and empirical knowledge of the mechanics of pneumatic tires and tire/vehicle systems, a requirement is defined for experimental data relating the shear forces developed at the tire-road interface to the kinematic variables of influence. Test equipment to satisfy this requirement consists of two complementary pieces of apparatus: a laboratory facility which is a modified version of the B. F. Goodrich flat-bed tester, and a mobile device which consists of a three-component (Fx, Fy, Mz) strain-gage dynamometer mounted on a heavy duty highway tractor. The latter provides a capability for testing at speeds up to 70 mph, normal loads up to 2000 lb, tire sideslip angles up to 18 deg, and steady state or programmed variations in longitudinal tire slip from fully locked (100% slip) to 30% overdriven (-30% slip). Representative samples of tire mechanics data obtained using the new equipment are presented and discussed.

Possible mechanisms for smoke formation in the diesel engine are discussed. Emphasis is placed on the effects of some engine and fuel factors on carbon formation during the course of combustion, including cetane number, fuel volatility, air charge temperature, and after-injection. The tests were made with a single-cylinder, open chamber research engine, with three fuels, covering a wide range of inlet air temperatures and pressures. There is evidence that smoke intensity increased with increase in the cetaine number of the fuels with inlet air temperatures near atmospheric. Increase in the air charge temperature caused an increase in smoke intensity for volatile fuels and had an opposite effect on less volatile fuels for the open chamber engine used. The smoke intensity was found to increase dramatically with after-injection, with all other parameters kept constant. The concept that flame cooling is the main cause for smoke formation is examined.

Cycle-to-cycle variation of pressure is a common problem in all spark-ignition engines. To examine the suspected influence of mixture-motion on this variation, a study was performed in a constant volume cylindrical bomb in which a jet of propane-air mixture was directed at the initial flame kernel. The rate of pressure rise of the jet-influenced combustion was compared to the rate for combustion in a quiescent mixture. The flame area, obtained using a spark schlieren photographic technique, and the calculated combustion rate were correlated with the pressure rate. The major results were: the rate of pressure rise increased approximately linearly with mixture jet velocity; and the width of the mixture-jet had an effect on the rate of pressure rise. A jet profile width slightly greather than the spark-gap produced the highest rate of pressure rise.

The object of this research was to learn more about the effects of mixture motion upon ignition in spark ignited piston engines, and to determine how variations in mixture velocity alter the combustion process. To provide effective means for producing and measuring the mixture velocity, all tests were made in a constant volume bomb, using mixtures of propane and air. The effects of mixture motion on the lean spark ignition limit, rate of pressure rise, and burning time were determined for mixture ratios ranging from stoichiometric to the lean limit. The mixture pressures corresponded to those in Otto cycle engines at the time of spark occurrence. The results reveal that a mixture velocity of 50 fps, relative to the spark plug, requires an enrichment of 17% with respect to the stagnant lean limit. Increases in mixture velocity were found to greatly increase the rate of pressure rise during combustion. This effect was more pronounced for lean mixtures than for stoichiometric mixtures.

The conventional ignition system utilizing an induction coil produces a spark consisting of a capacitive or high energy rate component and an inductive or low energy rate component. Predominant among conflicting arguments reported in the literature is the argument that the high energy rate component is the more effective for ignition of combustible mixtures. An investigation was conducted to measure the effect of the rate of energy release upon minimum spark ignition energy with electrode spacings greater than the quench distances reported in the literature. Lean, quiescent, propane-air mixtures were studied in a constant volume bomb. Results indicate that the minimum ignition energy decreased as the instantaneous peak power or peak rate of energy release was increased.

APPLICATION of nuclear energy for civilian automotive uses has possibilities, these authors say. Nuclear power for automotive applications, they feel, is technically feasible now where size and weight are not prime considerations; where size and weight are major parameters, discoveries of new materials for construction of nuclear-power reactors must be made. New materials are needed for reactor fuels, heat extractants, neutron reflectors, reactor construction materials, controls, and radiation shields which must have unique nuclear properties in addition to conventional engineering properties. This paper presents nuclear automotive propulsion devices in terms of technologies now available. The necessary radiation-shielding mass and weight requirements are presented for an ideal point-source nuclear-heat-power engine.

THIS paper reports work begun in 1935 at the instigation of the Murray Corp. of America. Methods used in studying the relations between the automobile seat cushion and its function in transporting passengers with greater comfort and less fatigue are described. Constructed for this purpose was a piece of apparatus called the Universal Test Seat, whose dimensions were completely adjustable with arrangements to vary the distribution of the supporting pressure in any manner which seemed most comfortable to the passenger. The authors describe tests made by use of this apparatus, present summaries of some of the results recorded and conclude that, to give the passenger the maximum comfort and least fatigue, the following mechanical objectives should be attained by the cushion: 1. To support the passenger over a large area to get the smallest unit pressure on the flesh; 2.