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Spark timing is known to be a critical variable for engine performance. It is important to measure timing under transient conditions as well as steady state timing. Such transients include accelerations, decelerations and rough idle situations such as those occurring in engines tested directly off the production line. Conventional measurement devices have performance limitations. Timing lights will not measure transients and are limited in accuracy due to tolerance stack-ups and parallax effects. Some spark protractors require the use of externally mounted optical shaft encoders which are accurate but require a difficult mounting procedure. Such encoders are also susceptible to contamination and vibration. Other spark protractors operate under the assumption of steady state conditions by equating time with engine rotational angle. This eliminates the need for a shaft encoder but suffers in accuracy under transient conditions.

A microcomputer-based, multichannel data acquisition system has been developed to acquire high frequency transient information typified by, but not limited to, automotive vehicle crash test applications. The system, which has been designed to be mounted on the test vehicle during a vehicle crash, will accommodate up to 240 channels. Each channel is comprised of a stand-alone microcomputer, memory for data storage, signal conditioning for piezoresistive transducers, automatic calibration and zero offsets, and programmable gain amplifier. The microcomputer is based upon a Motorola 6801/68701 microcomputer. The paper describes the design, development, and data processing characteristics of the prototype system.

The quality of outside supplied parts is an extremely important part of the total vehicle package consumers desire today. Although each supplier is ultimately responsible for the quality of its own products, a company's Purchasing group is the most influential customer activity in obtaining high quality. With the support of other customer activities, Purchasing selects the proper supplier, plans for and monitors production start-up, monitors supplier ongoing quality information and obtains corrective action as supplier quality concerns arise.

Many new driver information features are being added to today’s vehicles. This paper addresses the utility of these features to the customer and the functional parameters which must be specified in order to assure optimum performance of these features.

This report concerns the development of a small radio-telemetry torquemeter package intended to replace a current slip ring driveshaft torque meter system. Included in this report is a package description, a comparative test report and application recommendations. The torquemeter package developed can be used in any driveshaft, vehicle or otherwise, in place of a standard universal joint. Package constituents are a strain gaged universal joint cross and telemetry consisting of a modern FM transmitter and FM receiver. Transmitter power is available in battery form, or an inductive power supply can be built into the transmitter and receiver. The package was installed in series with a slip ring unit to conduct a comparative test utilizing both power supplies. Test results were not influenced by power supply and indicate identical data.

The objective of this paper is to illustrate an interactive computer graphics program developed to simplify the creation of finite element data which will be used for computerized structural analysis. Three-dimensional, part definition data in the form of basic design lines is input to the program and displayed on a cathode ray tube, and then a structural engineer creates the finite element definition using various computer graphics techniques. The procedures involved are discussed in detail, as well as the advantages over the traditional manual approach to element generation. Actual experience has demonstrated that this interactive computer graphic approach, in addition to being both accurate and reliable, is approximately fifteen times faster than the tedious manual method.

A new, low cost method to determine the accumulated structural loads in service (not to predict component fatigue life) that requires practically no on-board instrumentation is discussed. This method makes use of S/N fatigue life gages with high-gain mechanical multipliers bonded to a component. Permanent change in gage resistance results from the number of component load cycles and their magnitudes. These resistance change data are then used to reconstruct the load range history. The computer program on this method is listed in the Appendix. Results of laboratory tests conducted to validate the new method and evaluate the behavior of the multipliers over a practical range of operating temperature and strain magnitude and frequency are presented. The component load range distribution estimated by this method is compared to that measured by conventional methods for a vehicle operating on a proving ground route.

The analysis presented in this paper indicates that while 1700 lbf (7560 N) is a realistic femur fracture load for 30-50 ms duration impacts, the human femur can withstand higher loads for shorter-duration impacts. Experimental femur fracture data from cadaver and bone specimen tests are reviewed. These data are used to develop femur load fracture tolerance as a function of impact duration. On the basis of a measured 10% amplification of 1-2 ms input forces by the dummy, the cadaver fracture tolerance is proportionately adjusted to arrive at equivalent load levels for forces measured on current dummy test devices. Experimental dummy test device data are included and compared to the theoretical response of a mathematical model of the human upper leg. This comparison demonstrates that even neglecting the 10% amplification, there are still significant differences in the response of dummy and human upper leg structures for impact durations less than 3 ms.

The Experimental Safety Vehicle powertrain and fuel system developed by General Motors in compliance with Contract DOT-OS-00095 with the U.S. Department of Transportation include several special features: a low engine accessory package to meet the front visibility down angle of 8 degrees, engine and transmission mounting for retention at high decelerations, a light aluminum engine, an over-the-rear-axle fuel tank, and a unique evaporative emission fuel pipe routing. A comprehensive test program was planned and final testing to validate contract specifications was conducted.

Sound package engineering has always been an art developed through experience and much subjective road testing. Because the problem is complex, it is essential to have a logical procedure to achieve the most efficient sound package. The quiet car concept is proposed as a solution. Additionally, a plea is made for relevant automobile-oriented material test procedures to be recognized industry-wide.

There has been a lack of information on image brightness in automotive rear vision systems as related to the driver's needs. This paper presents data on driver evaluation of brightness, in the form of visibility and glare ratings of rear view mirror reflectance levels, based upon actual driving experiences. The effects of roadway types and various ambient lighting conditions are discussed, and ranges of acceptable reflectance levels are recommended. The study was a task group effort, performed for the SAE Rear Vision Subcommittee.

This study was undertaken to determine to what extent the passenger car eye ellipses have applicability in van-type truck package design and to produce a new practical design tool, if necessary. Eye positions of van drivers were found to be distributed differently from those for passenger car drivers and from those obtained by the procedure outlined in SAE J941b, Motor Vehicle Driver's Eye Range. There were produced in this study, tables of parameter values that a van-package designer can use readily to position eye-location distributions in space as a function of the azimuth and elevation angles of many targets in the forward field of view. These tables are available upon request from SAE.

The SAE Recommended Practice J963 “Anthropomorphic Test Device for Dynamic Testing” describes a standard 50th percentile adult male anthropomorphic test dummy. For nearly three years the Crash Test Dummy Task Force worked with the limited data available in selecting values for the body dimensions and ranges of motion. The data for specifying the values of mass distribution were developed experimentally as was a test procedure for determining the dynamic spring rate of the thorax.

This paper gives a comprehensive analysis of vehicle understeer-oversteer, utilizing theoretical and experimental approaches. It departs from the conventional by defining understeer-oversteer in the transient as well as in the steady-state condition under various types of inputs. The relationship between understeer-oversteer and directional and oscillatory stability is stated within this concept. The paper introduces new definitions, based on transient condition analysis, for direct and indirect understeer, directional and oscillatory stability, side-slip velocity, and others. It employs a computer program evolved from the equations of motion, shown in the comprehensive Appendix, to analyze the basic nature of understeer-oversteer. New procedures are outlined for quantitative determination of vehicle understeer and stability. The paper discusses the relationships between understeer, oscillatory stability, and the subjective “feel” of passenger automobiles.

The Taunus has been designed to meet the market demand for a car sized midway between the smallest and average sized European car, one that would provide exceptionally low cost of operation and rider comfort. The design described here had as us objectives low weight, low initial cost, superior performance and handling characteristics, comfortable seating and riding qualities, and ample luggage space. Tests show that the manufacturer has not fallen short of any of these objectives.

Under a new program of quality control in the field of powder metallurgy automotive parts called quality assurance, the supplier is made a closer partner with the buyer to get a more dependable part that consistently meets all requirements and specifications. The quality assurance program consists of review of potential suppliers, contract negotiations, initial quality assurance surveys, and routine quality assurance surveys.

APPLICATIONS of nuclear energy in automotive manufacture have been made principally in the field of radioactivity. These are grouped under the following categories: radiography, nondestructive testing, gaging and control, tracer techniques, and static neutralizers. Radioactivity techniques are being used in foundry operations to check stock and metal levels in cupolas and distribution of element additives. In steel operations, these techniques are being used to check assimilation of ore-concentrate fines and thickness of rolled sheet steel. Other applications include measurement of pipe and wall thickness in pressure lines and engines, and inspection of castings and welds for internal faults. Radioactive techniques for improving processes, quality, and materials have potentially universal application. Greater industrial access to reactors will permit broader study and speed the development of new applications of radio-activity in industry.

STYLING the Continental Mark II with a very low silhouette without sacrificing leg room, seating comfort, and driver visibility was accomplished by using a specially designed frame and a 3-joint driveline. These two features are the basic engineering innovations which make possible the Continental's distinctive classic styling. As a result of this structural analysis, Ford has produced an automobile that, according to the author, has technical advancements that are of value to the consumer.

AS a basis for the analyses of this symposium, a hypothetical car has been used to evaluate the engine power distribution in performance. Effects of fuel,-engine accessories, and certain car accessories are evaluated. The role of the transmission in making engine power useful at normal car speeds is also discussed. Variables encountered in wind and rolling resistance determinations are reevaluated by improved test techniques. Net horsepower of the car in terms of acceleration, passing ability and grade capability are also summarized.