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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.

A study was made of the deactivation of a pelletized base metal oxide catalyst which was evaluated in an eight-car fleet for accumulation of up to 18,000 miles in customer-type driving. The fleet test was carried out to determine the effects of two converter locations and four tetraethyl lead levels (0.06-3.17 g/gal) in the fuel on the effectiveness of the catalyst for the control of CO and HC emissions. Samples of the used catalysts were examined to ascertain the changes in BET surface area, size distribution and chemical composition of the contaminants deposited on the catalyst, and the patterns of penetration of lead contaminant. The major changes found in the used catalyst samples were correlated with the activity data obtained by the catalyst manufacturer on duplicate catalyst samples.

A method to stop jackknifing of all tractor-trailer vehicles by controlling the angle between the tractor and the trailer to a maximum of 15 deg of movement to either side is discussed. Most jackknifing occurs when the driver is forced into a unexpected lane change or into a panic stop to avoid an accident. Tests have proved that when a tractor-trailer is in a 25 deg or more angle, the vehicle is then in an “angle of no return” and a jackknife can occur. When road conditions are unfavorable, due to rain, ice, or snow, the jackknife will be more severe.

A simple jackknife restraint device which is integrated with the vehicle's normal braking system controls against the hazard of jackknifing in tractor/trailer operations. The device operates in conjunction with the vehicle's braking system, and the braking action restrains the vehicle from articulating into a dangerous jackknife attitude. The jackknife control mechanism, composed of four major parts, is described, and operation of the control is explained in terms of geometry of installation. Testing of the control is also discussed.

The conditions of road haulage in Europe are briefly examined, with particular reference to the main characteristics of vehicles, engines, and components used for the different applications. The importance of light and medium trucks in European haulage is stressed, taking into account the geographic characteristics, the existing road network, and the regulations presently in force. A typical range of light and medium trucks are then described as an illustration of the characteristics required. Future developments are considered with respect to foreseeable regulations for vehicles weights and dimensions, power-to-weight ratios, safety, and pollution requirements.

A digital computer simulation of an on-highway tandem axle tractor-trailer has been developed. The mathematical model is presented in state variable form and includes nonlinearities, such as suspension friction and shock absorber characteristics. The primary purpose of the simulation is the evaluation of suspension characteristics and their effect on truck ride. Comparisons showing good correlation between simulation and experimental results are presented for transient runs of the tractor-trailer over disturbances such as 2 X 4s and ramps.

Tuning techniques for controlling three principal modes of elastic vibration-vertical, torsional, and lateral-in the frame/body structure of a heavy-duty truck are discussed. The components involved in the solution of the shake problem are the frame/cargo-body structure, the cab mounting, and the powerplant mounting. The method followed in this experiment was a three-dimensional mathematical model analysis using a transfer matrix. The theoretical estimates showed appreciable correlation with the experimental results obtained by using a electrohydraulic shaker system. This technique, based upon a study of the effects of various components on the three modes of shake, was applied to production trucks and produced quite favorable results.

This paper describes the use of a road simulator by Fiat to determine the effects of vibration and loads imposed on various parts of a vehicle. The instrument has been effective in identifying vibration sources that induce fatigue or discomfort or which may cause inefficient operation or a breakdown. The laboratory tests include clear procedures for obtaining preliminary information or for tracing down existing conditions.

This paper describes a detailed theoretical and experimental study program of a 170-BHP (SAE net) Stirling engine, designed for a 1972 Ford Torino. The program was conducted by Ford Motor Company and N. V. Philips of Holland.