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Based on injuries determined by autopsies of 82 car drivers, who died after a straight head-on impact, and based on the deformation of the interior of the accident vehicles, the cause of the injuries was analyzed. This material can be divided into four groups, the characteristics of which are mainly defined by location and design of steering assembly, instrument panel, and seat. This evaluation led to a new explanation of the fatal aortic rupture at the classical site appearing very often, and to a number of conclusions relevant to the design of automobiles in terms of internal safety. Tests performed on the impact sled with cadavers and using various steering assemblies at impact speeds of approximately 37 mph confirmed the explanation of the mechanism of the aortic rupture as well as the satisfactory performance of a steering assembly with a shock-absorbing device which latter proved to be especially effective in preventing severe thoracic injuries.

Comparative evaluation of a variety of anthropomorphic dummies undertaken by the Office of Vehicle Systems Research at the National Bureau of Standards indicates a wide range of dummy performance. Dynamic tests, which were conducted on the NBS Dynamic Seat Belt Tester, simulated an impact environment with the dummies restrained by lap belt alone, or combined lap and torso diagonal belts of the type used in American automobiles. A variety of dummies, varying in construction from the most rudimentary to the most sophisticated, was tested. Test parameters included variations in impact velocity and acceleration. Each dummy was tested with both types of restraints, and sufficient tests were made to demonstrate the ability of the dummy to reproduce its reaction performance. These tests indicate that even when dummies are subjected to carefully controlled impacts with skilled technical personnel following identical procedures, it is difficult to reproduce test results.

Latest safety standards require that passenger car seats be only sufficiently strong to withstand 20 times their own weight during a collision. However, front seats should withstand the 30 G rear passenger impacts during frontal impacts. The current conventional car seat design cannot accommodate direct attachment of restraining systems or direct loading from rear seat occupants. This paper discusses seat concepts evaluated and reported upon in recent years. In addition, recommendations derived from full-scale collision experiments are discussed by the authors.

This paper is in part an extension of the laboratory studies reported at the Eleventh Stapp Car Crash Conference. The impact performance of laminated safety glass relative to penetration resistance, concussive hazard and lacerative damage has been expanded to additional laminated glass structures and installations at 45 and 90 deg impact angles. Severity Index values for a number of laminated panels have been obtained using a modified 22 lb headform that provides proper alignment of the internally mounted accelerometer with the test panel in free-fall impact studies. The effect of windshield installation on mean penetration velocity, laceration, and Severity Index in full scale laboratory testing is presented for rubber channel and adhesive mounting systems.

This program of investigation was conducted to determine the nature and magnitude of the physical parameters which most significantly affect the degree of trauma produced by impact to the knee. Drop weight testing of unembalmed cadaver limbs utilizing a load cell to record forces and high-speed motion pictures to follow the kinematics of impact were the experimental techniques used. The principal results were: 1. Movement of the leg and deflection of the flow are very significant in reducing the energy absorbed by the knee and hence the trauma produced. 2. The severity of trauma produced depends on both the impact energy absorbed and the peak forces generated. As the impact energy absorbed increases, the tolerance peak forces drop. Finally, consideration is given to the application of these results to improving transportation safety and to methods for evaluating such improvements.

Independent accident investigators tend to agree that knee impacts to current production instrument panels are not a serious injury-producing event. This paper begins by presenting the status of lower-limb injuries in field accidents. A second phase presents the design background of a GM-developed laboratory machine for knee impact area testing. The biomechanic considerations of the device are discussed. Its design, instrumentation, and operation are presented. A subsequent portion of the paper treats the selection of a responsible impact speed for testing. Full-scale sled runs were made with driver and passenger dummies, both lap-belted and unrestrained, to determine the actual relationship between the initial knee-to-panel space and the resulting impact speed.

Statistics on road accidents indicate that most crashes occur at relatively low speeds and that the number of vehicles involved is smaller as the speed increases. A mathematical model is herewith presented to establish basic factors from which, with a given safety device, the degree of injury to a passenger can be predicted and held down to a predetermined level. A mathematical model of the crash characteristics of the vehicle and of a schematic 2-dimensional occupant will give figures to be compared to those obtained experimentally in a vehicle crash with 3-point safety belts. A comparison will then be made of the severity of impact at passenger level for different models of cars and for various restraining devices.

Improving occupant survivability during a rollover accident requires a detailed analysis of the dynamics and statistical significance of a particular rollover situation as well as the structural performance of the vehicle involved. A two-dimensional model describing vehicle rollover has been developed which, in conjunction with a proposed index of performance, allows such an evaluation. Dynamic equations of motion for ground contact and airborne travel are used in the model which is programmed for solution on a digital computer. The model is validated by comparison of a graphics console display of the model trajectory with filmed sequences of a vehicle rollover. Validation of the model establishes the feasibility of this approach for predicting the rollover characteristics of a vehicle and determining relative safety performance between vehicles.

By duplication of glass fracture patterns, the feasibility of relating 22 lb headform impacts to head injuries sustained by occupants contacting the windshield in crashed vehicles has been established. For each suitable windshield sample selected from available 1966 to 1969 crashed automobiles, a vehicle analysis was performed. The unbroken sections of 33 selected windshields were subjected to dynamic loads using the 22 lb portable headform. This portable device mounted in a van is described. At impact, the deceleration and velocity were measured and lacerations rated on the basis of damage to simulated tissue and moist chamois. Achievement of duplication between headform and occupant head impacts permits a numerical assessment of windshield lacerative injuries and presents a tentative method for future programs involving correlation between laboratory and service performance.

A comparative analysis of detailed road crash data from four different environments is presented. Three of the studies were on-scene investigations of crashes from Adelaide, Australia; Birmingham, and Worcestershire, England. The fourth set of data was taken from ACIR reports by Cornell Aeronautical Lab., Inc. of predominantly rural crashes in the United States. Where necessary the data were reanalyzed so that the variables being discussed were compatible. Comparisons are drawn between speeds at impact, areas of impact, vehicle damage severity, seated position, injury severity, anatomical injury distribution, and causes of injury for the four sets of data. The results show that there are considerable similarities between rural crashes in England and the United States, and urban crashes in Adelaide and Birmingham. Further, urban crashes have quite distinct characteristics from rural crashes.

A survey of accident reports and experimental studies showed that the lap belt does not provide sufficient protection for the pregnant car occupant in whom fetal injury or abortion often resulted. A net-type restraint system was used on pregnant sub-human primates which were subjected to decelerations of over 40g in a forward-facing configuration. The animals survived multiple impacts without treatment and delivered healthy infants. The data presented include belt loads, body kinematics, and intrauterine pressure measurements.

Two anthropometric test devices have been developed to simulate two different portions of the head - these are the frontal bone of the cranium and a typical facial bone. These forms are intended for eventual use in evaluating the crash-worthiness of automotive hardware. This project concentrated on duplicating the fracture behavior of the bone structure; no attempt was made to develop a skin simulant. The creation of a facial bone test device is a more challenging philosophical problem than the headform. A test form which geometrically matches the complete facial skeleton may be too complex to serve as a practical test device. A form which typifies the more prominent facial bones is suggested as being more suitable for near future usage.

With a view to improving the significance of the results obtained during the simulation of the response of a man exposed to severe acceleration, the authors have studied a simplified model of the head to thorax linkage provided with a suspension. Preliminary calculations or responses from the behavior of models provide coefficients of stiffness and damping. The authors propose to authenticate experimentally these values and to compare them with values of volunteers in similar situations exposed to moderate forces.

A methodical investigation and measurement of human dynamic response to impact acceleration is being conducted as a Joint Army-Navy-Wayne State University investigation. Details of the experimental design were presented at the Twelfth Stapp Car Crash Conference in October 1968. Linear accelerations are being measured on the top of the head, at the mouth, and at the base of the neck. Angular velocity is also being measured at the base of the neck and at the mouth. A redundant photographic system is being used for validation. All data are collected in computer compatible format and data processing is by digital computer. Selected data in a stage of interim analysis on 18 representative human runs of the 236 human runs completed to date are presented. Review of the data indicates that peak accelerations measured at the mouth are higher than previous estimates.

Specific gravity is a nondestructive test used as a quality control check of the consistency of formulation and processing of brake lining. Specific gravity alone shows nothing about a lining’s ability to develop friction or to resist fade when used as a friction element in brakes. Specific gravity varies with the formulation of the lining. The specific gravity of sintered metal powder linings, particularly those which have steel backing members, is usually determined somewhat differently. Reference ASTM B 376 “Density of Sintered Metal Friction Material” (latest revision).1 The specific gravity and the range of specific gravity are peculiar to each formulation and, therefore, the acceptable values or range must be established for each formulation by the manufacturer.

This paper discusses the planning by United Air Lines for the introduction of the B-747 and DC-10. Involved in the planning are ground support equipment, facility modifications and other changes required to handle this aircraft through present facilities. A second phase of the planning involves a total automated approach to the new equipment and modifications required. New baggage/cargo equipment, in-flight dining facilities, larger boarding rooms, passenger automated ticketing and fare collection, as well as a new boarding system have been developed by United for the new aircraft.

This paper discusses a new concept for remotely entering manufacturing planning data into a computer system. By standardizing planning operations and using “on line” questioning techniques, the volume of paper generated manually is reduced, time spans for original and change planning for fabricated parts is shortened, errors are decreased and subsequent engineering changes are implented faster.

Advanced techniques to structure bills of material file on random access devices so that they may be used effectively by a computer are demonstrated. The balancing of requirements against supply orders for each material item in the product structure produces an economical inventory plan and can be achieved in an integrated data store bills of material file.

General Motors Research Laboratories has recently completed an Implementation Study of New Systems of Urban Transportation for the U.S. Department of Housing and Urban Development. This has included the study of improved methods for the design, analysis, and socio-economic evaluation of new systems of urban transportation by means of which comprehensive planning of transportation may be achieved, taking into account user needs, urban planning goals and overall social objectives. The study has also included the conduct of seven case studies, each of a selected new system concept in a particular urban transportation application. This paper describes the results of the seven case studies which apply a broad range of technology to some of the more urgent transportation requirements in certain American cities.

Using the Dallas-Fort Worth Regional Airport as a reference point, the author considers the major prerequisites of airport terminal planning. A general criterion is projected concerning expansion and automation. With passenger convenience in mind, the paper stresses the importance of building terminals in stages as increasing traffic warrants and suggests that suitable backup measures should be provided as security against automation failures. Terminal layout problems are discussed together with their possible solutions, as related to such factors as population density and available land space.