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This paper discusses the design requirements and operation of two onboard, self-contained, level histogram recording devices that can operate unattended for six months and store data in a removable digital memory. The paper describes the types of data the units record, data sampling and recording techniques, and memory data interrogation procedures.

A servohydraulic test center for the automobile industry is described in this paper. Mechanical, hydraulic, and electronic modular components are assembled for all-purpose test facilities. The fundamental structure of a controlled system with a cylinder-servovalve combination is explained. Some measurements and the quality of the reproducibility of the simulation of random loads encountered in road testing are discussed for two special test stands for axles and driveshafts.

This paper deals with the overall program of vehicle field data collection and instrumentation. In it, the philosophy of the vehicle durability test is discussed relative to the requirement of accurately duplicating customer usage. Advantages and disadvantages of various data collection methods are also discussed. A brief, nonrigorous discussion of data analysis is included.

One of the more important aspects of vehicle design is mechanical mobility. This term is a measure of how fast a vehicle can get from point A to point B without breaking while preserving the cargo and driver comfort. The road simulator has been used extensively as a laboratory tool to determine the durability aspect of the mechanical mobility problem. The objective of this paper is to show how the road simulator is used to provide the engineer with a validated mathematical model which he can then use to perform a parametric study to improve ride comfort. Specific areas of discussion are: mathematical model verification; correlation of model and simulator data; parameter adjustment to obtain improved ride. As a result of this study, the design engineer has a more precise vehicle model than has been available, and the test engineer has a verified laboratory simulation technique for vertical dynamic terrain inputs.

More meaningful laboratory testing can be achieved from test programs designed to better simulate the usage of the component or system in the hands of the consumer. Steering gears and linkages are adaptable to force measurement during vehicle operation. This data can then be used to program laboratory test equipment in a manner which simulates the force environment encountered in vehicle usage.

The intent of this study is to present effectual methodologies concerning single-phase and two-phase mixing problems which may conveniently be utilized by a design or developmental engineer. In particular, for single phase, turbulent, compressible coaxial fuel and air mixing problems, an index is presented which provides a sensitive indicator for determination of the degree of mixing in a given mixing chamber. Working graphs for several hydrocarbon fuel and air stream combinations are used to demonstrate the utility of the index. In addition, the index is shown to be of value for studying twophase mixing such as occurring in automotive carburetors. This paper further demonstrates the utility of the hydraulic analogy for studying complex mixing problems such as commonly occurring in automotive carburetors and manifolds, gas turbine combustors, and simple mixing chambers.

Many techniques are currently being used for different types of road simulation studies. These approaches vary from using a road simulator as an analysis tool for fatigue to durability simulation to predict the life of a complete vehicle in the laboratory. Different inputs to vehicles have been used, from the apparent straightforward approach of vertical inputs through the tire to complete simulation of combined loads through multiple inputs into the vehicle. An overview of these techniques developed over the past decade is presented. The analysis relates to the techniques and application of test equipment and methods of testing rather than the prediction or classification of actual results.

The purpose of this study was to obtain information useful for improving crash protection for small children. Previous research efforts have produced findings relating to accident characteristics in general, and those findings have been used to improve passenger protection. However, little work has focused on the particular characteristics of nonfatal and fatal accidents involving small-child passengers. Thus, this study compared accidents involving small children (five years old and younger) with accidents not involving small children, to establish the similarities and differences between those types of accidents. The principal findings of the study are briefly summarized in the following description of a composite accident in which a small child is an occupant of the car: The child is very likely a passenger in a car driven by a female between 20 and 35 years of age, who is not wearing a seat belt, and who has not been drinking.

In late 1971, Alderson Research Laboratories initiated the development of a totally new design for a similar pair of crash-test dummies in the three-year-old and six-year-old child sizes. The fundamental basis for this design was a compilation of recent child anthropometry surveys which served to define overall body weights and to target key external dimensions. Models built to conform to these targets were used to derive standards empirically for weight distribution and segment centers of gravity. These data are presented along with a description of the mechanics by which the sculptor's art, the anatomist's knowledge, and the machine designer's skills were blended to effect the transformation into the final human simulation models.

This paper presents the anatomical considerations and general principles of occupant restraint in the car crash environment with emphasis on the protection of the child auto occupant. Design criteria and typical performance problem areas in child restraint systems are discussed.

This paper discusses the overall concept and philosophy of field data acquisition and evaluation, incorporating results from an industrial tractor component. Since the scope of the subject is so large, the major part of the discussion is centered on the method of analyzing the data and life prediction. Some methods may or may not conflict with current procedures, and are presented as only one method of evaluation.

This paper describes a recently developed vehicle spindle transducer that is capable of measuring the three components of the force vector and the two components of the moment vector that simultaneously act on a spindle. The transducer dimensions are 4 X 4 X 1-1/4 in (105 X 105 X 32 mm) and weighs approximately 3 lb (13.5N). It is durable and can measure with less than 4% total error. The spindle transducer fits existing suspension systems without significantly affecting vehicle geometry or dynamic response and is, therefore, the only known spindle transducer that meets all requirements for size, weight, accuracy, and strength.

High-strength cold-rolled steels that are both formable and weldable can be produced based on either the columbium or vanadium-nitrogen strengthening systems. The critical aspects of chemistry and processing were determined for these steels in a laboratory program, and the results were used in planning a mill trial. It was found that a high-strength, formable product was favored by factors that produced a high hot band yield strength, large amounts of cold reduction, and annealing at low temperatures just into the range where full recrystallization occurs. In the mill trial, 80,000-90,000 psi yield strength hot bands, relatively high cold reductions (50 and 65%), and controlled batch annealing between 1180-1225°F were used to produce 60,000 psi minimum yield strength fully recrystallized product. Very good property uniformity was achieved in the 0.042 in and 0.050 in thick product with longitudinal yield strengths averaging 63,300 psi with a standard deviation of 1880 psi.

The complete design of a system to generate carbon monoxide gas to run a 350 cm3 automobile engine is presented. The horsepower output using CO, and the amount of gas required to produce this horsepower, is determined. The gas generator including heat resistant materials, filtering and cooling system, carburetor, hopper, feeder and gas storage system are designed in detail. The start-up system and procedure is described.

Interest in the use of high strength cold-rolled steel sheets is growing primarily because of the greater weight reduction that can be realized in automotive vehicles when the thinner gage, higher strength cold-rolled sheets are substituted for the heavier gage hot or cold rolled sheets currently used. Today's steelmakers have considered and tried a number of metallurgical alternatives and philosophies which have resulted in the production and availability, either in commercial or developmental quantities, of formable, high-strength, cold-rolled steels with yield strengths in the range of 50 to 120 ksi. These steels have as good or better properties as the standard, lower strength, cold rolled steels.

A laboratory simulation of dawn/dusk illumination showed that following vehicles could be detected equally well in plane and convex mirrors, and a night driving test showed that low- and mid-beam headlamps of a following car produced discomfort glare responses that were independent of whether the exterior mirror was plane or convex. Visibility of the following car was rated better with the plane exterior mirror. Measures of performance of drivers relevant to safety in lane changing and passing were not different when they used a plane or convex exterior mirror in conjunction with a plane interior mirror, and did not differ in the day or at night. When the initial speed of the overtaking car was 15 mph (24 km/h) greater than the subjects' car, drivers significantly underestimated the relative speed, indicating a potential cause of collisions with a following vehicle in lane changing and passing maneuvers.

Twelve passenger and three truck rear vision systems were evaluated under real-world driving conditions using driver looking behavior as performance measures. Glance duration and frequency at each rear vision device, as well as glances made directly to the side/rear scene, by six experienced drivers during 22 traffic maneuvers were recorded using direct video recording of eye movements. Over 20,000 rear information gathering glances were analyzed with regard to glance location, frequency, duration, total glance time per maneuver, and number of glances per maneuver for each system. Superior rear vision systems were identified and design implications regarding multiple device systems, convex devices and field of view were drawn. Ground plot field of view maps and Docket 71-3a target field of view coverage for each system was determined. A secondary study used expert judgment techniques to obtain estimates of rear scene zone criticality.

Several independent studies of sound level variation with nominal microphone distance are reported for a variety of equipment types tested in accordance with SAE exterior sound level test procedures. Good correlation between levels and distance is shown, although dependent on equipment type and mode of operation. It is concluded that predictions of sound levels at distances closer to the source than the normally-specified microphone distance can be made with reasonable accuracy.

Photographic and performance studies with a Rapid Compression Machine at the Massachusetts Institute of Technology have been used to develop insight into the role of mixing in diesel engine combustion. Combustion photographs and performance data were analyzed. The experiments simulate a single fuel spray in an open chamber diesel engine with direct injection. The effects of droplet formation and evaporation on mixing are examined. It is concluded that mixing is controlled by the rate of entrainment of air by the fuel spray rather than the dynamics of single droplets. Experimental data on the geometry of a jet in a quiescent combustion chamber were compared with a two-phase jet model; a jet model based on empirical turbulent entrainment coefficients was developed to predict the motion of a fuel jet in a combustion chamber with swirl. Good agreement between theory and experiment was obtained.

Better fluid mixing in automobile engines can contribute to fuel economy, smoothness of engine operation, and reduction of emissions. It is possible to improve the uniformity of mixture of fuel with air in the induction system, of trapped burned gas with the charge in the cylinders, and of air with the exhaust gas in a reactor. Criteria of uniformity of mixing are discussed and a more stringent criterion suggested. The mixing length concept is developed. Fluid flow mixing models for different passage geometries are presented and evaluated for mixing length. Mixing performance of the induction system and cylinders of a typical engine are estimated. Improved mixing means are proposed and described. Maximum uniformity of distribution of the charge involves effective vaporization of fuel and mixing with the air ahead of the intake manifold. Maximum uniformity of mixture and turbulence prior to combustion involves the mixture of the trapped burned gas with the charge in the cylinders.