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This paper identifies some significant relationships between vehicle characteristics, operating modes and the capability of the human operator associated with a remote control mission. These studies were primarily addressed to controlling a wheeled vehicle on the Lunar Surface, from an Earth Base. However, the information related to visual, motion, and sound cues to the operator, and modes of steering and velocity control of the vehicle, are general in nature and have potential Earth application. A significant improvement in the remote control of a vehicle is suggested by supplementing the visual cues with vehicle motion cues on the driving station (seat of pants) and sound cues related to work load or speed on the power train.

The first part of this paper defines lunar environmental factors which are pertinent to the design of a lunar surface mobility system. The second part discusses the design techniques required to solve the problems imposed by these environments. The definition of lunar environment includes only those data that are presently considered to be acceptable for the design of equipment for lunar use. The environmental factors defined are: extreme temperature range between lunar day and night, pressure, lunar gravity, surface characteristics (that is, terrain, soil), radiation, dust and micrometeorite impact. The effects of these environments upon the design and material selection for mobility system and subsystems are discussed. Specific examples of design techniques are demonstrated for the design of traction drive mechanisms, wheels, thermal control, and vehicle dynamics.

Rheological studies of an SAE 10W-40 motor oil were made over temperature and shear rate ranges typical of service. These include evaluations of both new and used oils. Determinations were made of the permanent viscosity changes during service, as well as the temporary non-Newtonian changes with shear. Data were taken at 60, 100, 210, and 250 F, which evaluated the oil from the initial first Newtonian to the second Newtonian regions. New oil viscosity measurements have little relation to the characteristics exhibited over most of the operating period between drains in an engine. Oils having similar initial viscosities can differ in service because of differences in formulation or service severity. It is evident that evaluation of the relatively “stable” used oil near or at the second Newtonian high shear rate region is the most informative. No convenient technique presently exists for such measurements on a large volume basis.

A good design requires knowledge of the inputs to the system as well as a means of evaluation of the result. For cross-country vehicle speed limits due to the vehicle's vibrational activity, the terrain profile becomes the important system input. A statistical technique for classification of this input has been developed and is presented as an analytical expression. With this definition and standard mathematical modeling techniques, a tool can be developed for aiding in the concept phase of the design process. Vehicle design trends for better cross-country speeds are discussed in terms of improving the ride comfort of a vehicle asevaluated in this way. Hardware examples of vehicle improvements are discussed.

This paper describes and illustrates the effect of three welding processes on the depth and hardness of the heat affected zone in low alloy steel castings. Also illustrated is an example of a production problem composite structure which highlights the importance of metal composition relative to the formation of excessive hardness in the heat affected zones. The summary includes recommendations for avoiding potential “built in” defects which can cause machining difficulties and/or possible component failure due to brittle fracture conditions.

The viscosity stability of polymer-thickened multigraded oils measured by the sonic oscillator failed to correlate with road test data when polymers of different chemical types were compared. A single cylinder Labeco CLR engine test procedure has been developed which correlates well with road tests and is independent of the chemical type of polymer used. Approximately 40 hr in the Labeco CLR engine are equivalent to 2000 miles of high speed driving.

The use of multigrade (V.I. improved) oils in automotive engines has increased significantly in recent years. However, the performance of these oils in terms of factors such as oil economy, wear, and noise, is not always equal to that of single grade oils. Although the initial viscosity of multigrade oils is related to both the base oil and the V.I. improver, the viscosity decreases with use, with the primary factors determining the magnitude of the change being the degree of shear and the characteristics and concentration of the V.I. improver used. This decrease in viscosity has been assumed to be the cause of the decreases in oil economy that may occur with oil use. However, viscosity changes are not believed to be the primary factor responsible since similar oil economy changes have also been observed for single grade oils. Nevertheless, the characteristics and concentration of the V.I. improver used can be a significant factor influencing oil economy.

The fundamental physical aspects of hypoid gears are defined, and derivations of complete basic formulae reviewed acquainting engineers with the problem’s relative simplicity. The formulae’s de-design applications are described; the reasons and results expected from basic design quantities being modified are discussed. The method is extended to the general case of any shaft angle Σ. Every type of bevel or hypoid gear design is available in specific detail — usually with applicable machine settings — from one set of formulae and one computer program.

Three new installations for the production of large steel slabs by the continuous casting process will come into production in the United States this year. This paper discusses the historical background of, and some of the metallurgical criteria used in, the design of these machines. The operating techniques used to assure quality finished products for various types of steel are also presented.

Once the basic drive gear parameters have been determined for an automotive rear axle, the mounting for these gears must be designed. The gears must be held in proper mesh under the various load conditions experienced in the axle to minimize gear misalignment and the resulting noise and fatigue problems in both the gears and the bearings. The basic types of successful gear mounting are reviewed, design consideration for the mounting components (carrier, case, bearings, etc.) and tests required to prove their design are discussed.

Direct casting of steels is an innovation in the steel industry. A twelve-month experience with this new method is the subject of this paper. Several steel specifications, among them 1018–1085, 1141, and 8620 have been directly cast into billet form. However this process has not yet been attempted with analyses less than 0.10% silicon, and no semi-killed or open heats have been directly cast.

Continuing Stirling engine development at General Motors has uncovered advantages of the powerplant never before fully appreciated. Smoke, odor, noise, and exhaust emission measurements indicate the attractiveness of the engine for applications in a “social” environment. Design details, particularly the external combustion system, are described here only in relation to low emission level. Measurements indicate that smoke and odor are practically undetectable. Sound measurements demonstrate the relative quietness of the engine. Additional data show that exhaust emissions, while very low, exhibit a strong dependence on burner design, air-fuel mixture ratio, burner inlet temperature, and exhaust recirculation.

Gear development is covered in a step-by-step manner including fitting the development to the vehicle. The type of machines and equipment used are briefly outlined. The controls necessary for producing uniform axle gears are covered in detail.

This paper discusses the development of a practical engineering tool to be used in predicting the per cent failures of mechanical components. In order to predict the per cent failures, it is necessary to convert life data of conventional S-N diagrams into strength data. The distribution function of these strength data is then determined. It was found in the present investigation that the three parameter Weibull distribution fits these data best. After finding the distribution function (Weibull) and its parameters for strength, the problem of distribution of stress is considered. On the basis of past experiences, the stress distribution is assumed to be normal. After values of the parameters of these interfering distributions of stress and strength have been determined, probabilities of failure of parts are calculated. An example is solved to demonstrate the application of the interference technique developed to predict per cent failures.

Developments in the plastic industry are increasing at a rate that makes it difficult for one to keep abreast of, and utilize these new concepts to advantage in his particular area of endeavor. Incorporated in one presentation is a summary of current developments in the ABS plastic industry, with particular thought given to how they may apply to future automotive applications.

The recent increase in smog and other air pollution problems traceable to internal combustion engine exhausts have created public interest in the search for new power sources for automobiles. An old favorite, the electric car, has received renewed attention, but battery technology is unable to offer a power source for a vehicle that will meet contemporary consumer demands for speed, range, and acceleration. The fuel cell has emerged from the laboratories as a practical electrical power source with much promise for vehicular application. This paper presents the state-of-the-art of fuel cells as related to electric automobiles and discusses fuels and economics.

The wide base light truck tire is a new low profile, wide rim tire concept, which significantly improves vehicle performance. The wide base tire also simplifies and standardizes tire and rim usage, making obsolete the variety of tire sizes, types, and rim styles previously available.

Volkswagenwerk AG is constructing a major research center at its main plant in Wolfsburg. A climatic wind tunnel, the most modern of its kind in Europe, has already been completed. With VW exports going to almost every country in the world, the tunnel has been designed to simulate all sorts of climatic conditions, including the atmospheric temperatures and humidities of all main climatic zones. Together with an infinite variation of those conditions, the tunnel can develop wind speeds up to 150 km/h (93 mph). The size of the working section permits tests to be carried out on full-size car models. Functional tests can be performed with a program-controlled dynamometer test bench. They include testing of engines under actual road loads and cooling conditions and the testing of heating and air conditioning systems. Aerodynamic forces to which a car is subjected can be measured with a mechanical rotating six-component balance.

This paper deals with a new 38,000 lb capacity truck tandem suspension of light weight. Four taper-leaf springs, each assembly consisting of two leaves, are arranged to provide a two-stage spring action. Equalization of load between axles is obtained through a long equalizer pivoted at the center. Load is distributed along the truck frame at six mounting points. Acceleration and braking forces are transmitted through torque eye leaves. Rubber bushings eliminate the need for lubrication at the pivot points.

The general problem of ground simulation in wind tunnel testing of automobile models is reviewed. Detailed studies using a fixed and a moving belt ground plane are described and the influences of model bottom detail, cooling system air flow, and ground clearance are evaluated. The final evaluation compares wind tunnel model results with the full scale vehicle on the road.