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For the purpose of increasing available knowledge of human dynamic response and tolerance to thoracic impact, and experimental investigation of both blunt and localized impacts to embalmed and unembalmed human cadavers is being carried out. This is a progress report to date. Force and deflection time histories resulting from midsternal A-P impacts over a six inch diameter area and from blows localized near the costo-chrondral junctions were measured and cross plotted to provide dynamic force-deflection characteristics. The extent of skeletal damage was assessed by both radiological examination and thoracic dissection and is presented in relation to the impact parameters. X-ray assessment of rib fracture damage was found to be inadequate, revealing on the average less than half of the fractures confirmed by dissection.

The neutral salt spray as an accelerated corrosion test to predict the service performance of decorative, bright-plated automobile trim gave such unsatisfactory results that the American Electroplaters' Society sponsored development of more rapid and reliable testing methods. The Corrodkote and CASS tests were successfully developed to duplicate the extent and type of corrosion occurring on parts in one winter's service in Detroit. It is suggested that unsatisfactory experience with the neutral salt spray as an accelerated test was due to failure to define service performance properly, and that the CASS test has proved to be more satisfactory mainly because performance criteria have been more realistically defined.

The single-shaft gas turbine engine has been proposed as a reduced-cost alternate to the previously used two-shaft turbine engine for application to passenger cars. The power output characteristics of the fixed-geometry single-shaft engine have been found to create performance difficulties, particularly with respect to standing-start acceleration of the vehicle. A review of the fundamentals responsible for these difficulties leads to the observation that variable compressor geometry can provide relief from this situation. Use of variable inlet guide vanes is identified as the simplest means of gaining this relief. Design factors influencing the susceptibility of the compressor to control by inlet guide vanes are considered. A method by which inlet guide vanes can be used to improve vehicle acceleration, without penalizing fuel consumption, is illustrated.

The objective of this paper is to give illustrative solutions for the types of combined structural and acoustic problems which arise in the finite element analysis of the automobile passenger compartment and to review related methodology. Analysis implementation using the NASTRAN (NASA STRuctural ANalysis) computer program is discussed briefly, including the use of modal compartment wall models and forced boundary conditions. The model is a two dimensional one, assuming a uniform pressure field in the cross-body direction. This simplification appears to be adequate for the frequency range of interest (20 to 80 Hz).

The purpose of this paper is to present a comparison of whole body, target impingement knee impact response for a Part 572 dummy versus that for anthropometrically similar embalmed human cadavers. “Response” is defined here to include the impact force-time history as sensed by 1) femur load cells, and 2) impingement target load cells for the dummy and by the target load cells for the cadavers. The data presented demonstrate significantly higher peak forces and correspondingly shorter pulse durations for the dummy than for the companion cadaver subjects under similar test conditions and at all velocity levels investigated. For the dummy, the ratio of forces measured by the femur load cells to those measured by the impingement target load cells averaged eight tenths.

A unique and very versatile circuit is described which converts changes in physical parameters such as capacitance, resistance, and inductance into a proportional pulse width modulated digital signal. This circuit, in combination with sensors which utilize these physical parameters in their operation, can be used to provide digital inputs to microprocessors and other digital control and diagnostic systems. Advantages of this particular circuit are its potential for high reliability, accuracy, and low cost. Several applications are described and an integrated circuit version of the circuit is discussed.

The versatile, compact, and simple swash-plate drive mechanism has been adopted for a variety of applications to give a reliable method of converting reciprocating motion to rotary motion. Historically, designers have concerned themselves only with the kinematics of swash-plate drives. This paper describes an analysis which combines swash-plate drive kinematics with hydrodynamic-bearing theory so a performance evaluation of the complete mechanism can be made. The predicted operating characteristics have been verified by tests on full-size models. Operating experience has shown the properly designed swash-plate drive system is a competitive method for converting reciprocating motion into rotary motion. A comprehensive bibliography of swash-plate drive literature is included.