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The engineer's traditional task of finding the best, most economical solution to technical problems becomes vastly more demanding in a time of energy and materials scarcity. Adaptability, flexibility, and quick access to suitable alternatives will acquire new significance in the next decade. Conservation measures, such as recycling, remanufacturing, and design for production and operational efficiency will increasingly figure in the development of transportation products. Beyond these and other changes in design emphasis lies a rising clamor for engineering accountability. Product liability legislation, many costly court decisions, and increased governmental regulation of many aspects of design all indicate growing public concern with the consequences of new technology. The trend toward establishing agencies for technology assessment will allow the engineer to participate in the evaluation of his designs in terms of their long-term social and economic impacts.

This paper presents the various features and operational properties of a two-dimensional mathematical model of crash victim motions. The earliest forms of this model can be traced to the early 1960s. Developmental work on two-dimensional models then continued both within the automotive industry and in independent organizations such as the Highway Safety Research Institute (HSRI). The most recent product of this activity is the MVMA two-dimensional mathematical crash victim simulation developed at HSRI for the Motor Vehicle Manufacturers Association. The features of this model include: 1. An eight mass representation of the human body where contact between the crash victim and the vehicle is represented in terms of independent force-deformation properties of the victim and the vehicle. 2. An extensible multi-joint neck and a realistically flexible shoulder joint. 3. A real-line representation of the vehicle interior or exterior where shape is given as a network of points. 4.

Development progress of the direct injected Stratified Charge Rotary engine program at Curtiss-Wright is detailed. Basic configurations are described and compared to both reciprocating stratified charge engines and the carbureted Rotary engine. Data and theoretical analyses are presented for progressive developments from initial feasibility testing in 1962 through current configurations now on test. It is concluded that the Stratified Charge Rotary Engine research efforts to date have demonstrated potential for an efficient, lightweight, compact, economic powerplant capable of broad range operations justifying further research efforts.

Improvements in cost or performance of an order of magnitude are occurring in the technology available to make small computers. This is occurring both in the processing unit with the microprocessor, and in the memories supporting the processor. As cost/performance is improved, the computer can be dedicated to more mundane tasks, such as carburetor control, while already being used in traffic light control. This development, permitting the use of arbitrarily large amounts of intelligence at low cost makes electronics capable of performing control functions formerly done with mechanical or hydraulic systems.

Whether we like it or not, increased usage of automotive electronics is going to focus attention on a class of components which may have little glamour or exotic appeal, but which will assume a role of vital and critical importance in tomorrow's automobile-the electrical connector. Though we may think of them as simple hardware, electrical connectors and interconnecting devices have reached a surprisingly high level of sophistication. This paper reviews the basic physics of electric contacts, with the objective of demonstrating how an understanding of the fundamental phenomena governing the behavior of electric contacts can be useful not only to designers and manufacturers, but also to users of electrical connectors.

Electronic reliability, as related to the automotive system, is discussed in four parts: the dual requirements of high reliability and of low unit price imposed on the semiconductor industry by the automotive system; how semiconductor device reliability has been and is being raised to levels of reliability commensurate with the needs of the automotive system; some suggestions as to how the semiconductor industry and the automobile industry might work together most effectively; and the overall situation as the semiconductor industry sees it. The automobile system represents a stringent environmental requirement for semiconductor devices. Reliability-wise, the requirements are not too different from those of military- and space-use situations. The automobile system imposes on the semiconductor industry two diverging requirements. One is a rigorous level of device reliability and the other is a demandingly competitive price figure.

Recent development effort concentrated on further improvement of emission control and fuel economy. The Bosch electronic fuel injection was advanced from using absolute intake manifold pressure as main input variable to an air metering system. This approach simplifies emission control combined with less cost gained by other improvements. Better fuel economy in combination with low emissions is achieved by closed-loop control employing the λ-sensor. The structure of this control loop allows the application of a self-adaptive control system responding to changing operating conditions of the engine. A further possibility is the closed-loop control at air-fuel ratios slightly richer or leaner than stoichiometric. This application widens the use of the λ-sensor to different emission control packages dependent on applicable standards.

The historical and current state of the art on transducers have been very well covered in papers presented to SAE, in particular in a paper by Mr. R.B. Hood at the conference in February this year (740015). The opportunity is now taken to forecast the direction of further development and future usefulness of various types of transducers as seen through European eyes.

The growth of electronics from the vacuum tube to the transistor and finally large scale integrated circuits and the impact of this growth on automotive electronics is discussed. Brief descriptions of current automotive electronic sub-systems are presented. Several experimental automotive integrated electronic systems, including diagnostic systems and display systems, which have been developed and tested are covered. A simple digital system containing inputs from transducers and driver commands; outputs to displays and actuators, and a central processor is used to describe the problems associated with installing an integrated electronic control system on an automobile. The problems associated with automatic radar braking are enumerated.

Through development and production of automotive electronics, we have faced various experiences and problems and set out requirments therefor. Now electric cars and traffic control systems are under development. JAPAN SAE and various industries are engaging actively to develop automotive electronics.

A brief evolutionary history is followed by a technical description of the current Bendix EFI system concepts. Application requirements are reviewed in relation to vehicle emissions, fuel economy and driveability. The advantages of feedback control are discussed with emphasis on the need for low-cost durable sensors. EFI is compared to the carburetor and other competitive systems in terms of cost, fuel control accuracy, and fuel economy. The current status of EFI electronic circuit technology and a projection of future generation designs are reviewed. System manufacturing considerations, including costs, are covered. Finally, the necessary application developments are reviewed, including the future potential of integrated electronic controls.

By an acceleration track operated through a falling weight (9, 11*) with a crash velocity of 50 km/h and a stopping distance of about 40 cm-corresponding to the crease region of many automobiles-the effect of three-point-retractor belts on 30 fresh cadavers and of two-point belts with kneebar on 19 fresh cadavers had been tested. The age of the cadavers ranged from 12-82 years. Qualitatively, almost all injuries known under the term “seat belt syndrome” could be reproduced. The dependence of the degree of injury in regard to the age was quite evident. It can be expected that persons over 40 years of age will suffer the same dangerous injuries as the tested cadavers, caused by the diagonal belts if the above mentioned crash conditions are existent. This will apply to both belt systems tested by us. The shoulder-belt-forces of all of our tests were between 340 kp and 1000 kp, but more serious injuries of the cadavers of older persons could be observed.

This paper reports the application of the Simulation Model of Automobile Collisions (SMAC) computer program to selected cases of actual highway accidents. Since SMAC was developed to allow accidents to be accurately reconstructed by operators without a detailed knowledge of engineering mechanics, recent developments have concentrated on providing a Start routine. This program automatically generates the inputs required for SMAC, including collision speed estimates, from a minimum amount of information available at the accident scene. A brief summary of how Start works is given, followed by a discussion of actual cases. The sensitivity of the final reconstruction to the various program inputs is discussed; this gives an indication of how the initial Start inputs may be adjusted to obtain a best fit with the minimum number of iterations of the program.

A combined program of accident investigation, staged collisions, and simulated collisions involving three-point harnessed occupants in frontal force collisions has provided a means of correlating injury with forces and/or other physical parameters associated with the injuries. With a strict screening to ensure complete data on each accident, 128 cases involving 169 occupants at barrier equivalent velocities from 2-53 mph were compared with the results from 11 staged collisions and 72 simulated collisions. There were 14 rib cage injuries ranging from single sternum fracture to seven rib fractures at velocities of 10-53 mph at injury levels of AIS 2 and 3. A single AIS 4 injury was the most serious injury and consisted of a ruptured spleen. The most serious brain injury was an AIS 2. Two cervical vertebra fractures were found, one of which was a 12-year-old male and the other a 76-year-old female. Only 14 occupants had AIS 3 injuries.

Since the airbag passive restraint system may be in general use in early 1976, and in fact is now an option on some automobiles, its potential biomedical hazards need to be thoroughly examined. Previous investigations in this area have been extermely limited. The objective of this study was to investigate the effects of local slap pressure of airbag deployment against the external ear and tympanic membrane and to measure its effects on subsequent hearing acuity. Adult and infant squirrel monkeys were used as experimental subjects, because the gross structure of their ear and tympanic membrane closely resembles man's. To create an adequate simulation of the airbag trauma, a small airbag was fabricated and mounted on a pneumatic impact facility. This device was designed to produce a specific velocity to determine the behavior of objects under impact conditions simulating accident kinematics.

High speed cinefluorographic studies were performed on anesthetized primates during graded, experimental blunt impacts of the head or chest. Cineframe data were analyzed frame by frame to identify dynamic anatomic movement patterns during each injury. The results indicate that the brain and heart undergo significant displacements within the first few milliseconds (ms) post-impact and these transient interior motions were correlated with physiologic and pathologic changes as well as impact force and deceleration.