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Precise air consumption measurement is of vital importance in the development of internal combustion engines. Considerable errors are introduced in measurements of airflow rates when conventional flow meters are used under pulsating flow conditions. Plate-type viscous flow air meters have been used satisfactorily under certain speed ranges. But it was found that the linear relationship between the flow rate and the pressure drop across the viscous flow air meter deviated at high engine speeds under the pulsating flow conditions found in internal combustion engines. Viscous flow meters have been designed using two main equations-pressure drop and Reynolds number equations. Deviation from linear relationship at higher speeds has led to an attempt at experimental verification of the frequency parameter theoretically analyzed previously.

A philosophy is proposed that there might exist a definite correlation between the engine parameter variations and the Fourier coefficients of different harmonics of the corresponding pressure diagrams and their derivatives. It is thus possible to establish the law of variation of Fourier coefficients with respect to a particular parameter. From these correlations, it is possible to predict a cycle, taking into consideration all the important parameters-injection timing, load, speed, flow processes, etc. Harmonic analyses developed in our laboratory are based on the principles of analog computation, to get results instantaneously, while the engine is running on the test bed.

A Wheel Slide Protection system is considered in which a hydraulic power source is used to modulate braking effort at each wheel of a vehicle. The reasons for selecting this type of power source are discussed, together with other parameters employed in the design of the system. System operation is described with particular emphasis on the functioning of the hydraulic actuators and their response to electrical control signals. Evaluation has been carried out on different vehicles over a wide range of surfaces. Certain observations are made as a result of these tests.

Use of braking systems in four passenger vehicles was evaluated during a 7300 mile trip across the United States. This paper presents an analysis of braking system temperatures and torques and vehicle speeds and decelerations that were measured during the trip. Similar measurements made during SAE fade and recovery tests are also presented and a comparison of severity levels is given. Requirements for specifying braking system performance at temperatures higher than those currently considered are discussed. The need for a new test to insure that vehicles will perform satisfactorily in service with approved brake fluids is shown.

A new Committee on Japanese Automobile Standards for Brakes has been established to issue standards covering road tests, dynamometer tests, nomenclature, etc. This paper discusses several of these. The Committee also reviewed the regulations and standards of various countries for comparison purposes. In order to have rational standards, ample data on vehicle usage, analysis of brake characteristics, and study of basic human engineering will be needed. Correlation among road tests, dynamometer tests, and test equipment must be established. Amalgamation of various national standards into a single international standard is desirable goal.

This paper discusses the problem of occupant protection in severe rear-end collisions from the standpoint of high performance seat structures and head restraints. Consideration is given to both fixed head restraints and to deployable head restraints. Two-dimensional computer simulations of occupant kinematics in a variety of rear-end collisions are utilized to provide initial performance criteria for head restraint design configurations. The resulting prototype system underwent a test and development program on an impact sled. The results of the various prototype performances and general criteria for high performance head restraint systems are discussed.

This paper attempts to serve three purposes: 1. To summarize the open scientific literature on muscular force applicable to pedals, and on the efficiency of foot motions on or between pedals depending on the body support and the body posture of the seated operator. 2. To discuss the applicability of such studies in automobile (or other equipment) design, especially to the design, selection, and arrangement of foot-operated controls. 3. To point out that for most conventional vehicles and equipment, modes of seating, and of pedal arrangement and operation follow largely common experience and tradition, and only partly scientific findings. For new man-machine systems, new solutions seem possible.

This paper describes two motion simulators and their application to research in whole-body vibration. One is a four-degree-of-freedom device capable of producing vertical, pitch, roll, and yaw motions. The other is a single-degree-of-freedom device that produces motion in the horizontal direction. Both have been used to acquire information on whole-body and visual response to vibration. Frequency response plots of some of the acquired data are presented. Procedures for assessing the severity of human vibration responses in terms of absorbed power are described and discussed. Brief descriptions are presented of studies that made use of the equipment and methodology dicusssed. The first is a concept evaluation of a proposed vehicle for use on the lunar surface. The second is a hardware evaluation of two seating devices for use in a wheeled vehicle in severe terrain environment.

Empirical models are presented which predict the threespace position of the torso when responding to reaches with the right arm. Models were derived which specify torso position in terms of the spacial location of 10 surface markers. These markers were positioned over palpable skeletal points of the spine and shoulder girdle. The necessary data were obtained through photogrammetric procedures utilizing four orthogonal cameras. The independent (input) variables to these models are the coordinates of the reach target. A supplementary, slightly more accurate, set of models was also derived in which the set of independent variables was enlarged to include the anthropometric dimensions of the subject. The second, concurrent phase of the analysis resulted in the derivation of a set of models which describes the configuration of the internal, torso skeletal system.

The frequent occurrence of erosion-corrosion attack in service failures of aluminum radiators suggests the need for a rapid test which will predict erosion-corrosion susceptibility in aluminum alloys under conditions simulating those in an actual radiator. This paper describes a multijet test apparatus which has been used to compare the erosion-corrosion resistance of aluminum alloys in antifreeze solutions at 200 F. Impingement velocities of up to 130 ft/s have been used. The effect of short-term jet impingement has been found to produce a mode of erosion-corrosion attack similar to that found in a 6951 alloy radiator after 40,000 miles of service. Attack appears to progress through several distinct stages starting with the development of a high density of pits which eventually become coalesced together at points of very high impingement velocity. The rate of attack has been found to be dependent on alloy composition and properties, jet velocity, and metal surface condition.

An ignition system with a 3500 h life capability has been developed for tactical military vehicles. An extensive test program was used to develop a capacitor discharge ignition system, composed of a capacitor energy storage system, a noncontacting metal detector timing system, a special coil, shielded ignition cable, and surface gap spark plugs. It provides ignition performance advantages, a single spark plug heat range, and is compatible with 4-, 6-, and 8-cyl military engines. The characteristics of various ignition systems were studied on the bench and on the dynamometer over a wide range of engine operation. The final design's capability to provide engine performance equivalent to the standard system was verified. The advantages and disadvantages of each ignition type is discussed.

Cycle-to-cycle combustion variation and engine emission levels are now recognized as effective indicators of engine performance. A system was devised that directly indicates combustion variation by measuring the work produced in a combustion chamber for every power stroke; it also continuously monitors engine emission level. Using this system, then, the effects of spark plug and ignition system variables on engine performance were examined. These criteria were employed in investigating the effects of spark plug gap size, gap location, electrode size and gap geometry, and the effects of spark timing, spark duration, and spark energy at various engine air-fuel ratios. In addition to studying each variable independently, statistically designed experiments to investigate the interactions between the variables were conducted. Although all the variables had measurable effects on engine performance, the most significant were spark plug gap size, gap location, spark timing, and spark duration.

A manikin that can simulate the final stable posture of a seated human being has been developed in order to evaluate seat comfort quantitatively and to analyze the biomechanical characteristics of seats. J-SAE 3DM, a manikin with the dimensions of a Japanese 50th percentile person made to imitate the SAE three-dimensional manikin standardized in SAE J826 was employed as the original; three additional joints were installed on its back pan to make it flexible. In this paper, the authors' view of seat comfort, on which their study was based, is summarized. Then the progress of development and various experimental results showing the usability of the final model are outlined.

The application of time-sharing computation to the calibration of aircraft gas turbine engine controls is described. The control is, typically, a hydromechanical unit composed of sensors, speed governors, servo systems, sleeve and pilot valves, feedback or follow-up devices, cams, and metering systems. Its complexity and required set-in accuracy present a challenge to even the most experienced calibration personnel. A high-speed time-sharing computer is brought to the service of these personnel to direct the adjustment process and to provide diagnostic and prognostic information.

As part of a continuing program to improve performance of copper and brass radiators and thus obtain improved material utilization, heat transfer performance of a standard cross-flow automobile radiator and stresses existing during operation were measured under normal operating conditions and at various other temperatures and pressures. It is well known that heat transfer performance of a radiator can be improved by raising the operating temperature and, thereby, the saturation temperature. Therefore, if the operating pressure and temperature can be raised while holding stresses within allowable limits by improved design with little or no increase in cost, a smaller, lighter and less expensive radiator should result. The standard radiator performance was evaluated using brittle coat testing, strain gages located at a number of points on the surface, and thermocouples at many points on the radiator surface.

Automotive radiators are currently used near their maximum operating capabilities. New temperature and pressure demands require stronger soldered joints to prevent failures. Quantitative data demonstrate a direct relation between soldering parameters and mechanical properties. Several new solders and conventional alloys have been examined. Highest strengths are achieved with silver-bearing solders, especially at elevated temperatures. A new alloy, with 3.0-3.8 Sn, 1.2-1.5 Ag, balance Pb, showed 100% strength improvement, which should raise current reliability and make the soldered radiator viable at higher operating temperatures and pressures.

Fluxless vacuum brazing is now a commercially feasible process for joining a large variety of aluminum heat exchangers, particularly the common automotive and aircraft types. The advantages offered by this process include: improved quality of the brazed assemblies, lower production costs, elimination of air and stream pollution, elimination of safety hazards, and the potential for improved product designs. This paper describes the process used to vacuum braze aluminum, analyses the overall cost of the process, discusses selection of alloys suitable for vacuum brazing, and deals with the application of the process to commercial production.

The static and dynamic strength properties and the fabricability of a specially processed, nitrogenized AISI 1010 steel are discussed. Typical applications are presented, and it is indicated that one important area of application for this steel is in parts that preserve the integrity of the passenger compartment to enhance safety. In addition, a method is described by which an estimate can be made of the static strength of the steel after it has been fabricated and installed in a vehicle.

SPREAD allows the user to perform complex stress and force analysis with little or no mathematical or computer experience. Extensive use of the program has shown that the resulting springs are much less prone to redesign than springs designed in the classical manner. The designs are usually more efficient, and the resulting product is closer to optimum when the program is used. The total savings in time, money, and effort have often been dramatic.

A new computer-related system that can be used by design engineers to perform both simple and complex descriptive geometry calcuations is described. The system, which requires no special programming knowledge on the part of the engineer, includes a free-cursor digitizer and a “menu” of calculations which are used in conjunction with conventional drawings to define various computations for the computer. The system eliminates the normal problems of graphic-to-digital conversion associated with existing methods of computer-aided design, thus freeing the engineer from hours of tedious and routine work.