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The design of successful over-snow vehicles is a complex problem because of the constantly changing media of snow over which they must operate. The vehicles also encounter a wide variety of surfaces other than snow. Careful consideration must be given to vehicle weight, ground pressures, suspension type, steering method, track cleat design, and overall vehicle weight-size relationships if the vehicles are to negotiate successfully the wide variety of snow and other surfaces over which they travel.

Initially, scientific investigators developed their own human simulators for use in adverse environment testing. This paper describes some of the history of the development of different types of human simulation techniques and their limitations. The increased necessity for more accurate simulations for automotive safety studies has created a need for additional sophistication. Sophisticated Sam, created by Sierra Engineering Co. under the sponsorship of the General Motors Corp., represents a significant advance in the state-of-the-art. The rationale behind the creation of a working simulator is presented along with proposed performance criteria.

All the primary inertia forces and/or moments generated by engines having three cylinders or less are not normally in balance by themselves and thus may be a great source of vibration for the frame supporting the engine. If the mass distribution of the crankwebs is selected in a proper manner, it is possible to determine arbitrarily the directions and the length ratio of principal axes of ellipses, which are obtained as Lissajous diagrams of inertia force and moment. This method can be effectively applied to reduce vibration in the frames. In this paper the appropriate inertia force and moment ellipse equations are developed and the analysis is outlined for optimizing the engine balance. Also the fundamental properties of the linear vibration systems excited by the elliptical forces as well as some experimental examples of elliptical excitation are detailed.

Efficiency vector representation with components of mechanical, volumetric, and overall efficiency is used for analysis and evaluation of hydraulic power transmission of positive displacement pumps and motors. Input and output power conditions are superimposed graphically on logarithmic scale coordinates providing comprehensive performance information and important interrelationships.

Thermal stresses have been evaluated in a nonmetallic gasket specimen by an experiment which employs a new thin foil stainless steel, compression resistant, heater of low heat capacity. Experimental results are predictable from a theoretically derived equation. An equation has also been derived for the thermal loads in a gasketed joint assembly. It considers the coefficients of linear expansion and stiffness coefficients for the bolt, gasket, and flange. The equation is discussed as a part of a rational engineering design procedure for calculating thermal loads in a joint assembly.

Ford Motor Company's decision to produce a new V-8 engine for introduction in the 1968 model year was influenced by the results of advanced design work began in 1964. The new engine design was conceived and developed to attain the prerequisites of luxury car applications, coupled with a primary objective of minimum unburned hydrocarbons and carbon monoxide emissions. This primary objective led to an engine design oriented around the induction, combustion and exhaust processes.

Honda Motor Co. has developed two small engine-driven portable generators which, by virtue of featuring cubic “appliance” design, are ideal for family recreational use. These designs involved exploration of many facets of engine cooling in enclosed spaces, design of ultra-small displacement engines, reduction of engine noise levels, improvements of permanent magnet generators, and optimization of user safety not previously considered in the portable generator field.

There has been considerable delay in the development of small-size, portable diesel engines compared with gasoline engines. This is due primarily to difficulty in overcoming such disadvantages as low power-to-weight ratio, hard starting in cold weather, and generally difficult operation. This has been the situation despite the fact that the diesel engine offers several important advantages, such as operation with low-cost, readily available fuels, low specific fuel consumption at partial power, reliable operation in adverse environments, and the reduction of fire hazard when using low-volatility fuels. The Honda Motor Co., taking advantage of experience and knowledge acquired with high-performance gasoline engines, has developed a lightweight, air-cooled, 9 hp diesel engine that overcomes most of the shortcomings of the small size diesel engine.

Cardio-thoracic injuries comprise a significant segment of the injuries sustained in automobile collisions. Because of the urgent need for additional information which can lead to prevention of these injuries, The Vehicle Trauma Research group at the UCLA School of Medicine has instituted a medical-engineering study of these injuries. The study has attempted to correlate pathophysiologic aspects of the injuries with the kinematics and biomechanics of the collision. Particular attention has been paid to the effects of restraining devices and the relationship of injuries of various wheel-column configurations including “energy absorbing” designs. Sixty-seven cases have been completely analyzed to date and are presented as a preliminary pilot study illustrating the value of this type of approach to auto collision injuries.

With a given transmission design, the machining accuracy of the gear is responsible for the frequent differences in noise. In general, the frequencies of the tooth contacts under load determine the noise. Gear errors and the assembly conditions cause highly different noise excitations that may be as well amplified by resonance as reduced by damping. The influence of the errors of helical angles and pressure angles, of axial and radial crowning, and of tooth spacing errors on gear noise are described, and manufacturing methods are explained which, with a manufacture based on tooth shaving, limit the said errors to such a degree that, as to noise, shaved gears are equivalent or even superior to ground ones. In particular, the dimensional changes during the hardening process are analyzed, as the distortions due to hardening must already be considered during the shaving process.

Vehicle noise resulting from vibration excited by the drive axle can be measured and controlled. Modifying the gear tooth geometry to assure the optimum design can then be achieved. Further benefits are obtained through determination of the critical path of vibration transmission from the axle into the passenger compartment, pointing the way to vehicle suspension revisions for additional noise control. A vehicle sensitivity index number, and a gear set quality index number are derived which can be matched, thereby specifying a gear set of known quality level for a vehicle of known sensitivity.

The electron beam welding process is commonly misunderstood to be a process applicable only to exotic materials and exotic applications. Recent developments in the electron beam process, such as the soft vacuum innovation, have made the process generally applicable to high-production welding for the commercial industry. In this regard, consideration must be given to the welding of rimmed, killed, carburized, and free-machining steels. Each of these materials involve certain welding considerations to which the product designer must address himself. The majority of the problems of welding common engineering materials by the electron beam process can be understood by examining the mechanism of electron beam welding and the practical aspects of the metallurgical and mechanical problems involved.

Resistance welding controls have developed over the years, changing the process from an interesting phenomena to a precise technology. From manually operated welders to numerically controlled machines, the user’s demands continually stimulated improvement and extension of the resistance welding processses. New structural materials, production requirements, and the demand for higher quality welds have brought about a high degree of sophistication in controls. The future welders will be machines that can “think for themselves,” with adaptive controls that sense changing welding conditions and adjust themselves accordingly to produce consistently high quality welds.

Inertia welding is a friction welding process using energy stored in a rotating mass as the source of heat and mechanical work. The process has been described in previous publications. The state of development of this manufacturing process, with respect to complexity of design and dissimilar metal welding, is the subject of this article. The successful applications of inertia welding now in production establish the utility of this versatile process while current developments portray exciting future possibilities.

Various laboratory methods for measuring chip resistance were compared and found to rate different finishes in different orders. A field survey showed that a gravelometer using gravel rather than other media correlated well with actual service results. The necessity of preparing chip resistance test panels which very closely duplicate the actual finish obtained on cars was shown. The nature of chipping has been studied and improved rating systems developed. Detailed drawings, test procedures, and rating systems for the SAE gravelometer have been proposed for publication.

A new type of acrylic finish has been developed which shows considerable promise as an automotive topcoat. Nonaqueous acrylic dispersion finishes combine exceptionally high application solids with reflow process capabilities characteristic of current lacquers. In addition, acrylic dispersions utilize low cost aliphatic hydrocarbon diluents and should readily satisfy air pollution requirements. Final film properties of dispersion finishes are equal or superior to those of conventional thermoplastic acrylic lacquers.

To promote improved automotive safety, present Federal specifications require the reduction of glare by sunlight reflection from a trim surface by restricting its intensity. The specifications imply that matte surfaces must be used. The alternative described herein reduces glare of reflected sunlight from reflective surfaces by decreasing the apparent size of the image. The necessary demagnification is obtained by utilization of surface curvature. The maximum radius of curvature is calculated by geometric optics.

The control principles and the design of a fuel injection system, developed by F.A.F Schmidt, are described. In this system, injection time and injection pressure are controlled independent of each other. The injection time is controlled by two rotating discs having slots, which are turnable to each other and which are turned by the influence of a centrifugal governor in connection with a three-dimensional cam. With the three-dimensional cam, a punctiform scanning of engine characteristics can be realized. Some results obtained with this injection system are shown, for example, fuel quantity characteristic, CO and n-hexane characteristic of a 4-cyl 4-stroke engine, injection pressure distribution dependent on crank angle, and consumption loops for injection and carburetor operation.

The conversion of the Military L-141 gasoline engine to the Texaco Combustion Process to achieve improved fuel economy and multifuel capability is discussed. Under contract to the U. S. Army Tank Automotive Command, the design and fabrication of both single cylinder and multi-cylinder versions of the engine have been carried out. Considerable engine dynamometer testing and preliminary evaluation in an M-151 vehicle has shown that stratified combustion over the required load and speed range, multifuel capability and a significant improvement in fuel economy relative to the standard engine have been attained. Design features of the prototype engine and test results to date are presented.

The development of a Type F automatic transmission fluid is presented by discussing the three components of a typical fluid: the base oil, the viscosity index improver, and the additive package. The trend towards fluids with improved oxidation stability and frictional characteristics is demonstrated by illustrating the three levels of performance required by the three major changes in Ford specifications over the past several years. This paper shows that development and evaluation of automatic transmission fluids have become quite complex and that it is now necessary to run a wide variety of bench, transmission, field, and proving ground tests. In addition, the development and properties of an additive package which exceeds the M2C33 E-F specification are described.