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Soft suspension springs are an essential requirement to absorb irregularities in road surfaces without transmitting excessive acceleration forces to the vehicle. Passive attitude control systems compensate for suspension height changes due to static load variations but leave a problem of excessive body motion in response to lateral and longitudinal acceleration. In this paper a system of active ride is described which retains the advantages of a soft suspension, yet controls body pitch and roll due to braking and cornering forces. Handling quality is enhanced by precise control of front to rear roll stiffness. Computed and experimental data is presented to establish fulfilment of the design objectives.

One class of ceramic materials that is being considered for application in diesel environment is the densified silicon carbide. The composition, microstructure, physical and mechanical properties of several members of this family of materials will be discussed along with illustrations of the current state of the art of component complexity.

A procedure to analyze and design adiabatic diesel engine components is developed. The analytical basis for the procedure is presented. An experimental study of related thermal boundary conditions in the combustion chamber is conducted. Mean effective gas temperatures as high as 2200°F are measured. A new adiabatic diesel piston, using a ceramic top, is designed and demonstrated using the procedure. Initial engine testing of the piston is encouraging, with full design power being achieved. The piston is considered the critical component in the overall development of an adiabatic diesel engine.

Some truck equipment manufacturers now offer a “Major Overhaul Program” to the users of digger derrick trucks. This program involves a complete tear down of the existing equipment and body; the rebuilding and remounting of the unit on a new truck chassis. This is followed by complete testing and finish work. The results produce a digger derrick truck in mint condition, under warranty, at a considerable savings when compared to a new unit.

This paper discusses the development of the Road Profilometer which is a Chevrolet 20 Series Van instrumented with transducers and data acquisition equipment to measure and record the magnitudes of frequencies present in road surfaces. The information collected provides data for vehicle structural and suspension system development. The transducers include two non-contacting, vertical displacement transducers mounted on each side of the vehicle and two vertically orientated accelerometers placed directly above the displacement transducers. The vertical displacement optical transducers utilize lasers for illuminating the road surface. Vehicle speed and distance data is accumulated from a non-contacting optical transducer employing an optical correlation technique. Data acquisition, digitizing and encoding, and recording of data on a digital tape recorder is controlled by a microcomputer.

The contemporary turbocharged aftercooled diesel engine is providing the world with one of the most efficient and dependable powerplants known to mankind. An adiabatic turbocompound diesel engine is analyzed in this paper to demonstrate that the contemporary diesel cycle without a cooling system could be the beginning of a new era in continued diesel engine efficiency, reliability and durability. The problems with the diesel cooling system encountered in service are presented. The consequence of an adiabatic turbocompound engine without any cooling system is treated for engine performance.

Non-contact inspection of highly specialized manufactured parts is no longer a philosophical topic of discussion with automotive engineers, but an absolute must for development of our products survival. Device and form of non-contact inspection systems has reached out of the research and development laboratories as diversified in approach as the application required of it by the inventive human mind. Challenges presented by the uniqueness of the individual inspection problem, and the systems available to solve that problem, are the two most prominent considerations facing todays quality engineers and manufacturing process engineers in the automotive industry.

The rising cost of new equipment has forced the user to consider methods of maintaining an updated fleet. The rebuilding of existing aerial device equipment has been performed with great success at substantial savings.

Contact and collision accidents of automobiles are spatial, and measurements of the path and its dispersion of the automobile and evaluation of operating performance from these measurements are important. There is residual path measuring equipment but there is a demand for more modern equipment. The author has developed equipment to automatically measure the position of an automobile by triangulation using laser beams and to process the data using a computer. This article will explain this equipment and give the results of some experiments in which this equipment was used to test automobile control as application examples.

Single cylinder SI engine tests were conducted with low octane primary reference fuel (PRF) blends and methanol. The investigated parameters were equivalence ratio, and PRF octane number ranging from 100 to 53 blended with weight percentages of methanol to 75 percent. In order to evaluate the performance of these different fuels, knock intensity, efficiency and emissions were considered. The results indicate that even a 53 octane number PRF blended with methanol displays some performance advantages over pure isooctane. This is best detected from the observed efficiency increase for all of the PRF blends except the 91 octane PRF blend. The improved efficiency is also higher than that of pure methanol.

The two year design-development program for the sonic carburetor is reviewed. Use of the sonic nozzle as an air flow meter, and the design criteria to achieve low unchoke points is discussed. The relation between sonic flow and improved fuel atomization and A/F ratio distribution to the engine is also discussed. Unchoke data and A/F distribution data are presented, and the tradeoffs between low unchoke points and good A/F distribution are explained. Conclusions are drawn relative to the overall benefits of the sonic carburetor.

Examples are given of apparatus and techniques developed or used by NASA-Lewis to make steady-state or dynamic measurements of gas temperature, pressure, and velocity and of the temperature, tip clearance, and vibration of the blades of high-speed fans or turbines.

Results of selected NASA research programs on rolling-element and fluid-film bearings, gears, and elastohydrodynamic lubrication are reported. Advances in rolling-element bearing material technology, which have resulted in a significant improvement in fatigue life, and which make possible new applications for rolling bearings, are discussed. Research on whirl-resistant, fluid-film bearings, suitable for very high-speed applications, is discussed. An improved method for predicting gear pitting life is reported. An improved formula for calculating the thickness of elastohydrodynamic films (the existence of which help to define the operating regime of concentrated contact mechanisms such as bearings, gears, and cams) is described.

This paper describes the development and content of the NASA-developed structural analysis computer program called NASTRAN. This program is in extensive use in the automotive industry as well as the aerospace and helicopter industries, and has become a standard of reference among finite element programs.

The NASA-Lewis Research Center (LeRC) has conducted, and has sponsored with industry and universities, extensive research into many of the technology areas related to gas turbine propulsion systems. This aerospace-related technology has been developed at both the component and systems level, and may have significant potential for application to the automotive gas turbine engine. This paper summarizes this technology and lists the associated references. The technology areas included are: system steady-state and transient performance prediction techniques, compressor and turbine design and performance prediction programs and effects of geometry, combustor technology and advanced concepts, and ceramic coatings and materials technology.

The paper introduces a session that reviews some NASA-derived technology that may be useful in the automotive industry. Several examples in the paper illustrate aerospace technology already at work in that industry. Services offered by NASA to facilitate access to its technology are described.

This paper describes a method for determining the effect of proposed geometric, material property, or manufacturing process changes on component fatigue life. The method integrates the application of field load data acquisition, analytical stress analyses, cyclic material properties, and strain based fatigue concepts. Fatigue life is then used as a major design change acceptability criterion. One of the key steps in this qualification process is the use of NASTRAN, a finite element stress analysis program developed by NASA.

This paper comprises a review of the scope and objectives of the Department of Energy's Electric and Hybrid Vehicle Program. Current status is outlined as of February 1978 for the demonstration and technology development efforts, including both vehicle and battery developments. Performance specifications are noted for the first 200-400 vehicle demonstration in 1978 and for the near-term Department of Energy integrated electric vehicle development. Although competitive success of electric and hybrid vehicles is questionable for the next decade, eventual commercial acceptance of such vehicles as a major petroleum conservation tool is predicted.

Two aspects of electric vehicle development in the UK are discussed; vehicle chassis, hardware and battery development and operational experience. Electric delivery vans of the one to two ton payload range in the Lucas and Chloride programmes are discussed. The improving prospects for molten sodium sulphur battery in large vans and buses is examined. The GLC ‘London Goes Electric’ scheme for placing up to 62 vehicles in service in Central London is covered in addition to the Electricity Council trial of 60 Enfield city cars.

The effect of soaking temperature on exhaust emissions has been studied using a variety of automobiles representing three different emission control levels and testing them at ambients of 20°C down to -30°C(60°F to -22°F). It was found that emissions of the three gaseous pollutants demonstrated a mild power relationship with ambient (soaking) temperatures. All regulated pollutants and fuel consumption were higher at -30°C than at 20°C: hydrocarbons (HC) - 3.5 to 9.2 times; carbon monoxide (CO) - 2.4 to 6.4 times; oxides of nitrogen (NOx) - only 1.1 to 1.4 times; and fuel consumption 1.2 to 1.8 times higher. Analysis of the data has indicated that HC and CO emissions from the cold start phase of the Federal test were the most sensitive to soaking temperature. With NOx emissions the soaking temperature sensitivity was fairly constant throughout the three phases of the Federal test.