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A nonlinear mathematical model is used to predict head motions during an automotive rear-end collision. The physical characteristics of the seat back are extremely important factors in the mechanics of the torso and head of the car occupant. This paper studies the velocity and displacement as well as acceleration patterns of the subject's head and torso on absolute and relative bases. Once these patterns are established, mathematical experiments are performed to study the variation in patterns produced. Specifically, the concept of the yielding seat back (damped and undamped) is studied as a design concept for attenuating the impact experienced by the subject in the rear-end collision.

An introduction is given to some mathematical optimization techniques applicable to shock and vibration absorbers and isolators. Simple tutorial examples are presented illustrating the Phillips and Wiener procedures and the method of Minimization of Auxiliary Effort. For shock inputs, optimization criteria of the form “minimize the maximum value of x(t)” are important. It is shown that these can be approximated by the more tractable criterion “minimize with suitable T” using conveniently small values of n. Published applications of optimization techniques to shock and vibration are briefly reviewed.

A mathematical statement of the problem of optimum design of shock isolation systems is presented and two computational methods of solution are examined. These are termed the direct and indirect methods of design optimization. The direct method is the more conventional, and employs numerical search procedures common to problems of constrained minimization. As such, its main limitations stem from the usual computational burden associated with large problems. The indirect method is akin to modern techniques of control theory, and appears applicable to large, complex systems; moreover, it provides information useful to the designer on the bounds of possible system performance that is not available through the direct method. An extensive bibliography is presented.

This paper presents the state-of-the-art of active vibration and shock isolation, with theoretical considerations limited, to idealized single-degree-of-freedom systems. Servocontrol systems postulated for use as active isolator mechanisms are reviewed with emphasis placed on active isolation systems that have been reduced to practical operational hardware. Performance characteristics of mechano-pneumatic and electrohydraulic isolation systems are discussed in detail and are compared to those of conventional passive isolation systems. Experimental data are presented to demonstrate performance characteristics of these active isolation systems in aerospace applications involving the protection of missile inertial guidance platforms during launch and a jet aircraft pilot during severe turbulence encounters. Optimization analysis and synthesis concepts are discussed relative to the design of active vibration and shock isolation systems.

A parametric analysis of the life support systems was completed, from which scaling laws were developed and adapted to computer solutions. This new tool permits the evaluation of a great variety of life support system types and combinations. The interdependencies and interrelations within the life support system itself can be evaluated, as well as the interactions between the life support system, spacecraft, and other systems. Representative data are presented for several partially closed life support system configurations usable for manned Earth orbital missions. The life support systems are principally affected by alternative degree of closure, the functional methods selected for the various subsystems, and mission requirements.

The design of vibration tests involves satisfying both objective and subjective goals with uncertainty about the true reliability of the design. A procedure is outlined whereby the constraints, goals, future states of nature, and candidate test designs are identified. A general statistical decision theory model is used to evaluate the designs based on maximizing expected utility. The paper emphasizes utility theory and utility function formulation. An example spacecraft test problem is presented.

Structural design is discussed as related to the optimization of components and systems. The tools of mathematical programming (including nonlinear, linear, and dynamic programming) employed in the optimization process are treated. Illustrative examples are included.

A vibration isolation system is investigated theoretically and experimentally which combines an active element with a passive system. The resulting system, here called a hybrid vibration isolation system, seeks to give stiff response at low frequencies and soft response at high frequencies without a large resonant response at intermediate frequencies. It is shown that fairly good response can be achieved with reasonable choice of operating parameters.

Some of the fundamental limitations of roll control and vibration isolation are analyzed and discussed. Optimum roll responses to a step input in lateral acceleration are derived from the calculus of variations. The responses show that a pendulous suspension (where the roll center is above the passengers) can be made to exert zero net lateral acceleration on passengers; whereas, a finite lateral acceleration will always be present during maneuvers of vehicles equipped with conventional suspensions (where the roll center is below the passengers). The lower limitation on roadway-induced vibration is presented as a trade-off between vibration and the clearance space between the sprung and unsprung masses or between the sprung mass and the roadway. Finally, the substantial benefits accruing from the use of preview control (where the roadway ahead of a moving vehicle is sensed) are presented.

This paper discusses operational experience with the integrated Saturn V launch vehicle, to be used as the booster for the Apollo manned lunar landing mission. Emphasis is placed on NASA's management approach to the solution of technical problems rather than on the problems themselves. Launches to date are summarized, with emphasis on the Saturn V. A discussion flight anomalies and corrective management action is included. The paper concludes with an appraisal of the program to date and makes recommendations for future guidance.

This paper presents a light, but reverent, discussion of some of the Douglas operational experiences on the Saturn V/S-IVB stage. Certain relevant aspects of earlier work on the Thor intermediate range ballistic missile, the Saturn I S-IV stage, and the Uprated Saturn I S-IVB stage are also discussed.

The purpose of this paper is to relate some of the operational experience on the second stage (S-II) of the Saturn V launch vehicle. A review of the performance of the major stage systems during static firing and flight operations is presented. The malfunction experienced was the premature shutdown of two J-2 engines. The S-II stage has accomplished all of its mission objectives except that the propulsion demonstration was only partially accomplished because of the engine shutdown.

A concerted, systematic program for design and development of a high reliability booster has been developed by The Boeing Co. for use in the NASA Apollo Manned Space Flight Program. The S-IC program stressed discipline in analysis, testing, and management to insure a consistent and reliable end product. Evaluation of the operational experience from this program resulted in a complete systems analysis program being established which encompassed single-point failure mode and effect analysis, double-point failure mode and effect analysis, and analysis of potential human-initiated failures. These activities serve to predict stage reliability, identify reliability critical components, and provide a constant feedback to design and management to permit timely hardware redesign, retesting or revision to operating procedures to eliminate or minimize the probability of failure.

Abandonment of the concept that gas engines can be operated economically using straight mineral oils and clay filters and the switch to detergent oils designed for specific use in natural gas engines has been handicapped by attempts to use conventional automotive or diesel metallo-organic detergent oils, and by the attempts to develop ashless oils without investigating all of the parameters and pitfalls associated with the use of ashless dispersants. At present, the weaknesses of ashless oils can be overcome only through the use of a balanced combination of the proper base stock and certain metallo-organic detergents. Careful analysis of engine operations over relatively long periods of time will demonstrate to the operator that ash from a properly designed natural gas engine oil does not adversely affect engine operations. It has been our experience that laboratory engine tests are of relatively little use in the evaluation of natural gas engine oils.

Tests employed for the evaluation of used lubricating oils generally involve the determination of changes in viscosity, insolubles buildup, contamination with metals, fuel, water, glycol and other physical and chemical changes. The author attempts to point out the relative significance of these various tests in terms of engine operation. Engine test data is also presented which shows the relationship between the oil condition measured by some of these tests and the engine performance characteristics. The data indicates that increase in alkalinity improves rust protection and reduces engine varnish and PCV valve restriction in certain additive combinations. Engine wear appears to be associated with the accumulation of contaminants in the lubricant measured as pentane insolubles and total acid number.

This paper presents analytical lubricant technology for determining the condition of 2 and 4 cycle automotive and railroad diesel engines through used oil analysis. The paper supplements ASME paper 64-OGP-16, and SAE paper 650139 wherein two new analytical techniques were presented for gas and gasoline engine oil analyses. These two methods, in addition to used oil atomic absorption spectroscopic analysis, are presented herein and shown to predict diesel engine condition with regard to deposit level, maintenance practices, and equipment malfunction, as well as to provide information on lubricant condition and contaminants.

Applying systems analysis to the C-5 the basic analytical tools used were computer programs which evaluated C-5 characteristics and determined cost effectiveness. Three programs used to evaluate characteristic effectiveness were the loading program, productivity program, and effectiveness analysis program. The fourth program, a life cost model presentation, determined airplane cost effectiveness, and is presented in two levels-conceptual and contract definition phase, and acquisition phase. A description of Pert-Tech techniques is also presented outlining how managers on the C-5 program were able to assess the technical health of the program and to pin-point problem areas where action had to be taken during developmental work. Systems analysis applications presented illustrate one of the first cases where detailed alternatives on a major transportation system were measured against total system effectiveness to attain maximum product performance.

Methods presently in use by the Penn Central Railroad for draining diesel locomotive engine crankcases are discussed. We believe these criteria apply to other types of diesel as well as gasoline engines. The author explores the use of oil insoluble values as limiting factors of an oil's effective life. The effectiveness of blotter spot interpretations and their meaning in evaluating the condition of used lubricating oil is pointed out. Although controversial, the author feels it as well as later modifications of the technique can be most meaningful to the engine fleet maintainer.

Design criteria utilized in the development of an air conditioning system for a 50–70 passenger jet aircraft for the short haul market are presented. Because the aircraft’s mission requires high speed over short stage lengths, special problems result. A short haul aircraft is described and related to the environmental system. Concepts for air conditioning that were considered as well as the one recommended are discussed. Final air conditioning design is reviewed relative to performance, operation, safety, reliability, and maintainability. The result is a package with larger than average cooling performance per passenger and design features not found in any other aircraft environmental system.

IDEAS (Integrated Design and Analysis System) is a new approach directed toward the rapid definition of design loading conditions and internal structural element loads needed for the sizing and analysis of the primary structure of an entire aircraft. It is an integrated collection of many different kinds of computer programs and formalized calculations which are performed in particular sequence. Complete integration is of prime significance. Output data from any one kind of computer program is in the precise format required as input for subsequently used programs of the system. System capability is sufficiently broad to provide state-of-the-art analysis procedures for both variable-sweep supersonic aircraft and fixed-wing subsonic aircraft. It treats all applicable flight maneuvers, landing and catapult conditions, taxiing conditions, gust and flutter analyses.