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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.

Eight full-scale collision experiments were conducted and 73 collision fire case studies were investigated to provide data relating to fuel system failure modes and susceptibility of fuel system designs to collision fires. Data regarding impact speeds, nature of injuries, and climatic conditions are included. Results of extensive laboratory experiments provide specific ignition conditions for common fuels and define ignition hazards of exhaust systems and electrical and lighting circuitry. The physics of crash fire atmospheres is described, including air quality, radiant and convective heat transfers, and the relationship between burn physiology and occupant escape time. Design concepts are suggested for limiting fuel spillages, ignition sources, and thermal stress to motorists.

Human volunteers were exposed to increasing levels of sled acceleration and velocity during simulated barrier crashes while seated in a padded, bucket automobile seat and restrained by an advanced, passive, three-point belt which contained energy-absorbing fibers and was integral with the seat structure. By muscular tensing, bracing, and riding with the head flexed, two of the subjects were exposed to crash velocities as high as 30.0 mph (over 33 mph, total velocity change), without suffering significant pain or injury.

This paper describes the results of 13 tests simulating a frontal impact against a fixed barrier at 50 km/h and 25 g. The results showed a marked increase in the severity of injuries with increasing age and more frequent chest injuries than head and spinal injuries. The tests were made with two types of restraint systems, both of which seemed equal in occupant protection.

Longitudinal impact tests were conducted on the knees of four seated embalmed cadavers using an impact pendulum. Impact force and femur strain histories were recorded, and peak force at fracture was determined. The results show that femur stiffness (average = 3.29 MN) for impacts is nearly the same as for static loads. Peak fracture loads varied from 8731-11570 N, all above the fracture criterion proposed by King, Fan and Vargovick. Strain histories and fracture patterns suggest that bending effects play a major role in determining the response of embalmed cadaver femurs to longitudinal impact.

Biomechanical guidelines for the development of an anthropometric dummy knee have been lacking. Quasi-static tests were performed on adult male volunteers and embalmed cadavers to define the force-penetration characteristics of the knee when loaded by a rigid, crushable foam of known crush properties. The test subject was seated erect with the thigh horizontal and lower leg unrestrained. Axial thigh (femur) force and knee penetration were recorded as a block of foam was pressed against the knee. The test was conducted incrementally with increasing peak load, and a new foam block was used for each increment. This enabled evaluation of the foam indent volume as a function of peak load. Pertinent anthropometric data are presented for each subject, and normal distribution theory is used to develop percentile scaling rules for the knee response. Loading corridors for biomechanically sound 50th percentile performance are suggested.

The chest impact data of Kroell, et al., and Stalnaker, et al., were examined to determine the relationships that might exist between the physical characteristics of cadavers, impact conditions, and responses. It was found that while the Kroell male, Kroell female, and Stalnaker data had similar physical characteristics, their responses were not related to their physical characteristics and impact conditions in the same manner. Regression equations were found that fit the Kroell male data extremely well. Based on a regression analysis of the Kroell male data, scaling rules were developed that allowed performance requirements for chest response to be defined for 5th, 50th, and 95th percentile dummies. Previous response requirements were for 50th percentile dummies only and were based on averaged responses from subjects whose average characteristics differed widely from 50th percentile characteristics.

Previous studies of human thoracic injury tolerance and mechanical response to blunt, midsternal, anteroposterior impact loading were reported by the authors at the 1970 SAE International Automobile Safety Conference and at the Fifteenth Stapp Car Crash Conference. The present paper documents additional studies from this continuing research program and provides an expansion and refinement of the data base established by the earlier work. Twenty-three additional unembalmed cadavers were tested using basically the same equipment and procedures reported previously, but for which new combinations of impactor mass and velocity were used in addition to supplementing other data already presented. Specifically, the 43 lb/11 mph (19.5 kg/4.9m/s) and 51 lb/16 mph (23.1 kg/7.2 m/s) conditions were intercrossed and data obtained at 43 lb/16 mph (19.5 kg/7.2 m/s) and 51 lb/11 mph (23.1 kg/4.9 m/s).

For investigating the safety of passengers impacting windshields, above all in test series in the development of new glass constructions, the phantom test is practically indispensable. But since the evaluation values for internal safety-head acceleration and lacerations-can only be properly measured when the movement carried out at impact is realistic, the tests must be carried out at the impact angles occurring in motor vehicles. The results of the phantom test depend largely on the construction of the phantom head. Due to the use of phantom heads of varying construction (because of lack of test regulations), the results of the individual testing installations frequently deviate from one another.