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The paper illustrates the high degree of correlation now attainable with practical vehicle test results, using a reduced-scale dynamometer. The techniques for achieving this state-of-the-art are described in relation to the parameters generally known to influence vehicle/laboratory correlation. As a result of the investigation, the following additional parameters are submitted: history of pad use, correct temperature/time simulation of the car by the machine, and rate of work input during a test. The simulation item is the subject of a special study in which the thermal conditions in a brake are examined on an analog computer by means of a 2 d.f. model. A discussion of the possible applications of the scale dynamometer leads to the conclusion that a machine could now be developed to provide meaningful data on linings for the use of friction material, brake, and vehicle manufacturers, as well as legislators.

Emission engineers are currently evaluating several catalyst substrate designs, such as monoliths and beads, for use in automotive converters. One of their problems is to design converters that provide adequate control of the engine exhaust emissions but that do not significantly increase back pressure. In this paper, the design tradeoffs between pressure drop and conversion efficiency are examined for monolith, bead, Raschig ring, and wire mesh catalyst substrates. It is shown that monolith substrates provide the best flexibility when designing converters to satisfy vehicle installation space and engine back pressure requirements. Bead substrates have higher potential conversion efficiencies than monoliths but are less adaptable to vehicle space requirements.

The paper briefly reviews the principle of a dynamometer that permits laboratory simulation of the road behavior of an actual passenger car, under all conditions. Also presented are the results obtained with United States Federal Motor Vehicle Safety Standard 105 on a passenger car making both road and simulator tests. These results show an excellent correlation with road testing. Furthermore, a comparison with road testing allows us to state that a better quality of testing is obtained with the simulator test bench.

Latest results with dual catalyst systems incorporating GEM nickel-copper alloy NOx reduction catalysts are reported. Progress in optimizing system design to provide rapid warmup, maintenance of operating temperature, and controlled carburetion to maximize NOx removal and minimize the risk of over-temperature is discussed. Results of vehicle durability tests of GEM catalysts run on dynamometers are also presented. Rapid warmup of the catalyst system can be obtained by keeping NOx reduction catalyst mass low and utilizing the ability of the reduction catalyst to oxidize CO, H2, and HC under net reducing conditions. This ability to oxidize CO, H2, and HC is also used to maintain system operating temperature. Carburetion is controlled to ±0.4 A/F with a four-barrel research carburetor, the design of which is described in detail.

The Federal Standards pertaining to the exhaust emission control of the 1976 model year automobiles presumably demand the catalytic conversion of the pollutants involved. Provided the air-fuel ratio is maintained at a stoichiometric value, some problems (for instance, fuel economy) can be solved. A closed-loop system was developed, consisting of an electronic fuel injection system and a special oxygen sensor, called the λ-sensor, in the exhaust manifold. First results on vehicles indicate that this control system offers an promising solution to the reduction of harmful contaminants. The closed-loop system can be used with a three-way catalytic converter or with a dual-bed system. It has not yet been investigated whether the durability of the two systems is adequate, apart from the general problems of the durability of each catalyst.

The use of a new tool for the evaluation of driver visibility requirements is described. The tool takes the form of a program written for an interactive computer graphics system. XYZ coordinates of window openings, visual obstructions, mirror systems and driver eye points are supplied as data. Polar coordinate line drawings are then generated on the graphics display simulating what a driver would see directly to the front and sides or indirectly to the rear through a rear view mirror. The program can be used to evaluate driver visibility in terms of forward and rearward visibility target areas in actual vehicles or in vehicle concepts (clay models, prototypes and car body drawings) which are sufficiently well developed to permit the specification of window coordinates.

This paper presents an analytical treatment of a mechanical-mathematical model of an air bag inflation process integrated with a model for the interaction between the air bag and a standing child dummy. The inflation model consists of a one-dimensional gas dynamics analysis of the flow system which delivers the gas to inflate the bag. The interaction model then provides a method for calculating the forces exerted by the inflating bag on the standing child. The results show that the unacceptably high contact forces recorded in standing-child air bag tests are due to impact of the unopened portion of the bag on the standing child. A single-membrane concept is thus suggested to reduce this impact severity.

This paper is a summation of various efforts to develop and improve passive restraints (air bags) for front-seat compact car occupants. The results of 140 system sled tests and of two full-scale crash tests with the system are presented. Several tests were conducted with offset and obliquely positioned occupants. Numerous other tests were also conducted to compare the 5th percentile female with the 50th and 95th percentile male.

The field of view required to see various classes of objects from automotive vehicles was investigated by Ford Motor Company in a series of research projects that included literature surveys, analytical studies, human factors tests and photographic road-traffic surveys. This study was concerned with field of view 360 degrees around the vehicle to the following classes of objects:

Presented in this paper is a discussion of the General Motors air cushion restraint system for the driver position. A discussion of the overall system operation and performance is followed by a detailed description of the components including the crash sensors, steering column, and air cushion module.

After a brief review of early steam car performance, the results of current research are summarized with emphasis on problems such as emissions, safety, cold-start delay, freezing, and choice of working fluid, control systems and fuel consumption. It is concluded that a Rankine cycle powerplant can meet 1976 federal standards for emission. Alternate fluids for steam engines are discussed, but water is still competitive, as is the piston engine.

International concern over air quality and the recognition that the internal combustion engine-powered passenger car is a contributor of atmospheric pollutants has imposed restrictive design criteria upon both the automobile manufacturer and the petroleum refiner. For the passenger car engine builder serving the American market, these criteria have been specified by the emission standards required by the Clean Air Amendments of 1970. On the other hand, gasolines for these low-emitting passenger cars have only recently been specified and their required quality and performance characteristics have not yet been completely spelled out. This paper discusses the influence of emission control requirements on future gasoline quality. Lead antiknocks, hydrocarbon composition, and gross physical properties are among the factors considered and an effort is made to quantify the effects of changes in these characteristics on emissions and to estimate their impact on the industry.

Born nearly a quarter of a century ago, the movement toward commercial use of the gas turbine engine in automotive vehicles has slowly progressed to the point of imminence in certain heavy-duty applications. Recently, interest in light-duty application to the passenger car has been stimulated by concern over exhaust emissions. This paper serves as an introduction to the vehicular gas turbine engine. It traces the developmental history of the engine for automotive use, provides some insight into the characteristics of the engine components and their function in the complete powerplant, and finally touches upon some recent activities in the gas turbine field. As an educational device, treatment of these topics is intended to be too comprehensive for the casual reader, yet sufficiently elementary that the gas turbine specialist is not challenged.

This paper gives a comprehensive analysis of tire tread wear utilizing new experimental and analytical techniques. An explanation of the mechanics of tread wear is postulated and related to tire traction. A differentiation between grip and friction is introduced as an important factor controlling wear and traction, and a quantitative definition and experimental technique for measuring road microtexture and its tread wear effectiveness is proposed. The paper introduces new concepts which provide a basis for quantitative determination of factors controlling tread wear and provide new methods for measuring and calculating tire force energy, road surface abrasiveness, tire wear energy, and severity. Good correlation between tread wear and measured values of tire force severity and tire wear severity are established. A potential method for predictions of tire tread wear on a computer is developed.

Light alloy wheels offer many advantages over steel wheels, particularly with regard to styling. A wheel, however, is a safety critical component and performs an arduous engineering function. The performance and safety of a wheel can be enhanced by casting in light alloy, a fact well known to racing car designers. To ensure that advantages of light alloy wheels are not marred by poor reliability requires scrupulous control of all aspects of production. GKN has evolved an approach that ensures this control by direct involvement at all stages of manufacture in its modern integrated-wheel facility.

A study was undertaken to determine the thermal stability, in the absence of poisons, of a PTX®-Type IIB monolithic oxidation catalyst and to demonstrate durability on a vehicle by actual road testing. Effective control of emissions of hydrocarbons and carbon monoxide for 50,000 miles was achieved in the absence of system or engine malfunctions. No increase in carbon monoxide emission and a gradual increase in hydrocarbon emission was seen over this period. The increase in hydrocarbon emission was compared to that observed for a series of catalysts, hydro-thermally aged in the laboratory, indicating that the gradual increase was due primarily to thermal effects. An analysis of the lead distribution in lead-free gasoline was made, indicating that with 0.05 grams per gallon maximum lead level (per EPA regulations) less than 0.03 grams per gallon would be valid for certification of automobiles.

The effects of lead and sulfur in gasoline on the activity of two platinum oxidation catalysts have been studied using engine dynamometer units. Under the steady-state conditions used, no poisoning due to sulfur was observed. Prolonged operations with lead up to 0.07 g/gal reduced the hydrocarbon (HC) conversion activity of the catalysts in proportion to time and lead concentration, but did not affect carbon monoxide (CO) conversions. The overall extent of lead poisoning was relatively minor, however. Catalysts exposed to the equivalent of 25,000 miles' operation with a fuel containing 0.07 g of lead/gal still met the original 1975 federal emissions standards of 3.4 g/mile of CO and 0.41 g/mile of HC when tested on an experimental vehicle. Exposure of platinum catalysts to exhaust from 20 gal of fuel containing 0.5 g of lead/gal caused an immediate drop in catalyst activity, but this loss was rapidly recovered when operations continued with a lead-free fuel.

“Fault tree” is a name given to a logic diagram that develops all of the subsystem and component faults and combinations of faults which can result in particular system symptoms or faults. This type of logic diagram can be extremely useful in all phases of automobile design and service. Applications are discussed to the following areas: 1. As a reliability tool for identifying and cataloging specific problems, to preclude their being incorporated in new designs. 2. As a diagnostic aid to maintenance personnel in systematically screening potential vehicle performance problems. 3. As an aid in assessing accident causation factors and the potential contribution of vehicle defects to accidents. Examples in each area are presented. Particular emphasis is placed on the value of such logic diagrams over conventional troubleshooting charts and manuals in aiding mechanics to pinpoint specific problems.

Improved vehicle safety and increased vehicle weight are closely related and critical parameters. The capability of analytically relating vehicle crashworthiness and weight variation is necessary in order to apply a systems engineering approach to the overall vehicle weight problem. This has been accomplished at AMF by the development and use of an on-line user-oriented computer program to obtain vehicle weight as a function of crashworthiness parameter variation. The results of a crashworthiness-weight tradeoff study performed for an optimized experimental safety vehicle (ESV) design are reported in this paper. The analytical model and computer program are presented and discussed.

Platinum, palladium, and copper-chromium oxidation catalysts for exhaust emission control were exposed to exhaust gases from a steady-state engine dynamometer test in which the amount of oil consumed per unit volume of catalyst was high. When unleaded gasoline (0.004 Pb g/gal, 0.004 P g/gal) was used, conventional SE oil caused somewhat greater loss of catalyst activity than an ashless and phosphorus-free (“clean”) oil. Chemical analysis of the catalyst indicated that phosphorus from the conventional oil was probably responsible for the difference. However, a test run with low-lead (0.5 Pb g/gal, 0.004 P g/gal) gasoline and “clean” oil caused much greater catalyst activity deterioration than either of the tests with unleaded gasoline.