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The need to predict weapon capabilities in combat has caused anxiety since man first picked up a club to defend himself. The complexity of modern systems has made the job of determining wartime effectiveness during peacetime extremely complicated and expensive. Two related efforts are currently underway providing valuable vulnerability and lethality data to military planners and weapons systems designers. The Joint Live Fire (JLF) Program has been providing ballistic vulnerability and lethality information on fielded front-line systems since 1984. The Live Fire Test (LFT) Legislation, effective in May 1987, is providing similar information on our systems currently in development.

The article is devoted to the problems of joint optimization of mass, power and reliability characteristics of the thermal control system and radio electronic instruments for long term mission spacecraft of high reliability requirements. The instrument operation reliability depending mainly on cooling medium temperature, the problem of optimum temperature level choice in the thermal control system taking into account the maintenance of the reliability required is of great interest. The technique developed allows to choose the optimum instrument redundancy rate as well as the optimum temperature level in the thermal control system at minimum values of mass and power characteristics.

Detergent additives in automotive gasoline fuel are mainly designed to reduce deposit formation on intake valves and fuel injectors, but it has been reported that some additives may contribute to CCD formation. Therefore, a standardized bench engine test method for CCDs needs to be developed in response to industry demands. Cooperative research between the Petroleum Association of Japan (PAJ) and the Japan Automobile Manufacturers Association, Inc. (JAMA), has led to the development of a 2.2L Honda engine dynamometer-based CCD test procedure to evaluate CCDs from fuel additives. Ten automobile manufacturers, nine petroleum companies and the Petroleum Energy Center joined the project, which underwent PAJ-JAMA round robin testing. This paper describes the CCD test development activities, which include the selection of an engine and the determination of the optimum test conditions and other test criteria.

Post Consumer Recyclate (PCR) or Post Industrial Regrind (PIR) use to manufacturer thermoplastic (or thermoset) automotive parts and components, has increased over the last 20 years. Therefore, automotive designers are challenged with the question of how recycled material differs in performance from virgin? In addition, automotive OEMs are requiring increased durability of thermoplastic parts and their attachments (joints), so that warranty costs, associated with interior squeaks and rattles are minimized. From this durability need there have grown several techniques for determining an attachment's performance capabilities, they are: strip-to-drive torque ratios, screw pull-out force, and clamp load fall-off. For example, if a boss has a low strip-to-drive torque ratio (< 3) there exists the potential for assembly and/or field failures.

The object of this study has been to develop a quantitative description of the mobility of the human torso, including the shoulder girdle, neck, thoracic and lumbar vertebral column, and pelvis. This has been accomplished by a systematic multidisciplinary investigation involving techniques of cadaver dissection and measurement, utilizing cineradiofluoroscopy for joint center of rotation location, anthropometry, radiography, and photogrammetry for selected positions and motions of living subjects, and computer analysis. Positional and dimensional data were obtained for 72 anthropometric dimensions on 28 living male subjects statistically representative of the 1967 USAF anthropometric survey of 3542 rated officers, including bone lengths of the extremities and vertebral landmarks. Normal excursion of these limbs was measured in the living, utilizing the landmarks established in initial cadaver dissection.

Objective: To determine if the Articulated Total Body (ATB) Model can realistically model the joint reaction forces generated at the hip joint during posteriorly-directed manipulations of the femur. Methods: A 50th percentile adult male positioned supine with the pelvis constrained, the leg in 0° and 20° of abduction was modeled. Dynamic manipulation forces with a constant period of 0.24 seconds and amplitudes of 250N, 500N, and 750N were applied 10 cm distal to the center of the right hip joint along the longitudinal axis of the right femur in the anterior to posterior direction. Results: The percentage of the applied force seen at the hip joint decreased with increasing load amplitude. Conclusion: This study represents a novel and successful application of the ATB Model to elucidate the time-dependent forces produced within the hip joint during dynamic joint manipulations commonly performed by healthcare practitioners.

This paper provides a method for Design (Size) optimization. Finite Element Software provides the Graphical User interface (GUI) to pre-process and post process the optimization variable and results. It deals with the stiffness values for different joints using Finite Element Software. To simulate the joints in Finite element model we need stiffness values to simulate the same. There are so many techniques to find out the stiffness values using known variable. To confirm the stiffness values we have used Design Sensitivity and Optimization technique in MSC.NASTRAN SOL 200. Bush element plays a major role to simulate the joints in Finite element model. To model the simple one dimensional Bush elements we need 6 stiffness values which are 3 translations (Kx, Ky and Kz) and 3 rotations (Kxx, Kyy and Kzz). It is therefore necessary to study the behavior of the joints and its characteristics and controlling factors. The current work is an effort to study the phenomenon of joint stiffness.

The Joint Strike Fighter Integrated Subsystems Technology (J/IST) Demonstration Program will demonstrate the integration of secondary power & cooling functions and the replacement of central hydraulics with electrical power to achieve significant Life Cycle Cost (LCC) savings and warfighting benefits. LCC savings of 3 - 4 percent are projected for J/IST technologies versus 1995 state-of-the-art conventional subsystems. J/IST is being accomplished by a team of Boeing, Lockheed Martin, and McDonnell Douglas, under three separate but interrelated contracts. The major technologies are the Thermal/Energy Management Module (T/EMM), T/EMM integration with the engine, 270VDC power management and distribution, and electric primary flight control actuation. Affordability and warfighting benefits assessments are ongoing and will be updated based on the results of the final J/IST demonstrations.

This paper describes the features and capabilities of a comprehensive yet flexible computational tool ORBIT developed for analyzing journal bearings (e.g. connecting rod bearings and crankshaft bearings) in internal combustion engines. Several techniques for solving the hydrodynamic Reynolds Equation have been developed within this methodology which can be used appropriately by bearing designers/analysts depending on the level of detail required. Besides ideal circular bearings, this simulation tool also enables the analyst to consider the influence of a) non-circular journal bearing geometry, b) oil-feed holes/grooves, c) surface roughness, d) journal misalignment, e) rise in oil temperature and f) bearing elasticity effects (EHL) on bearing performance. The capabilities of the simulation code are demonstrated through a series of validation and case studies.

This paper deals with the classic problem of dynamically loaded bearings. It differs from previous, related work by being directed toward the engine designer rather than a Ph.D. thesis committee. An automotive engineer, aided by a computer, can use the included computation procedure to get a reasonable picture of bearing performance. He can discover the effect of changes in speed, power, dimensions, and oil on potential trouble spots, and he can see the difference in behavior of main bearings, crankpin bearings, and wrist pin bushings. Typical orbit diagrams, based on this procedure, are included for comparison with photographs of test bearings for which the journal paths were drawn.

AUTOMOTIVE engineers, who have to deal with high-speed high-load journal bearings and are confronted with fear of the consequences of “ragged-edge” thin-film lubrication, will find much of interest and value in this report. It covers the information obtained and conclusions reached as a result of the extension of research into the region of thin-film lubrication, in which little investigation has heretofore been made. Tests made in a four-bearing machine, using both high-tin babbitt and high-lead bronze bearings and operated on lubricants of various viscosities over a wide range of speed and load, showed conclusively that the coefficient of friction depends directly upon the viscosity even in the thin-film region. They indicated defnitely that the friction coefficient is more likely a function of ZN/√P than of ZN/P.

Methodology to determine the clutch facing sensitivity regarding judder in the vehicle. Vehicle “Judder” is identified as low frequency and high amplitude vibrations that, depending on their intensity, can cause uncomfortable driving. Today the judder test is performed in the sensitive car concerning judder, however it takes long time due to the need of assembling the complete clutch set (disc, clutch cover, flywheel) for each test. So the aim of this work is to develop a methodology for classification of facing sensitivity regarding judder, however in subscale bench test, because the idea is not only to reduce test time but also to speed-up the facing material development. The preliminary results are very promising due to a good correlation between subscale tests and the vehicle.

Methodology to determine the clutch facing sensitivity regarding judder in the vehicle. Vehicle “Judder” is identified as low frequency and high amplitude vibrations that, depending on their intensity, can cause uncomfortable driving. Today the judder test is performed in a sensitive car concerning judder, however it takes long time due to the need of assemble the complete clutch set (disc, clutch cover, flywheel) for each test. Therefore, the aim of this work is to develop a methodology for the classification of facing sensitivity regarding judder. However in subscale bench test, because the idea is not only to reduce test time, but also to speed-up the facing material development. The preliminary results are very promising due to a good correlation between subscale tests and the vehicle.

CAR engineers are haunted again by the ghost of very low-pressure tires, which they had hoped several years ago was laid. These tires are one of the elements of airplanes that they hoped not to have to adopt. As was the case with the balloon tire of 10 years ago, the super-balloon was offered by tire companies in answer to a demand of car owners for a replacement tire that would give a softer ride. The question now disturbing car engineers is whether super-balloons must be offered as regular or optional equipment on new cars. They have an eye and sales appeal but doubts exist regarding their safety in event of blow-out, their susceptibility to puncture, their relative mileage life, their effect on steering and the like. Mr. Lemon discusses these points and the engineering changes that will be necessary in the chassis if super-balloons are to become regular equipment.

The ability of performance-based brake testers (PBBTsa) to accurately determine the braking capability of commercial vehicles was investigated through a field study of over 2,800 trucks and buses. Under certain conditions, good agreement was found between the observation of brake-related defects by visual inspection and the measurement of weak brake forces by a PBBT. It was determined that the PBBTs' assessment was an independent measure of a vehicle's as-is braking capability, and should not be expected to correlate well with a visual inspection under any condition. It was also determined that predictions of stopping capability should be possible combining the PBBT results of the brake force and axle load measurements with certain assumptions regarding brake application time and road/tire coefficient of friction.

More than ten years have passed since the establishment of the AUTOSAR consortium. Today, AUTOSAR has become a well-established standard for automotive electronic control unit (ECU) development and network design. In fact, several original equipment manufacturers (OEMs) now mandate AUTOSAR when sourcing ECUs. With that being said, the standard is getting more complex as new concepts are added with each new release, making integration an increasingly difficult challenge - let alone a challenge developing it alongside ECU application functionality. This paper addresses the integration of AUTOSAR 4.x basic software stack into an ECU project and offers proposed flows for the integration process starting from the ECU extract to a fully configured AUTOSAR stack.

The A-weighted sound level accounts for the bulk (but not all) of the jury's reaction to the sound of trucks coasting on a variety of tires. A component of the jury's reaction is related by the study to the manner in which the sound decays after the vehicle passes the point of observation. This component also appears to depend strongly on the characteristics of the sound. The jury's reaction shows two forms of distortion: end-of-scale compression and temporal drift. The analysis attempts to account for these factors and to see beyond them into the jury's basis for reacting.

The Mexican automotive manufacturing industry is considered to be the leading and most competitive sector in this country’s economy, and it is well known for its use of modern manufacturing technologies and philosophies. This paper address some selected aspects of the application of Just In Time initiatives in this industry, using the results of a research conducted in a selected group of automotive manufacturing plants from the central zone of Mexico, focusing mainly on the following elements: Identification of the manufacturing technologies and/or philosophies used in order to support the implementation process. Identification of the methodologies used by these companies, in order to implement the Just in Time. Identification of the main obstacles during the implementation process, and how these industries overcome them. Recommendations for the companies that are currently planning to initiate this implementation process.

This paper examines the four phases of Just-In-Time, as it is used at the Ford Motor Company. The phases are as follows: 1) awareness or understanding, 2) statement of commitment, 3) pilot projects, 4) launch or full implementation. Each phase is explained, as are the potential benefits. At Ford, communication among and contributions from all employees are considered vital, as is commitment from management. The necessity of management commitment is discussed in detail, as are means of obtaining that commitment.

Just-In-Time production involves more than strictly inventory and processing changes. It necessitates changes in the physical plant. This paper reviews the changes which were made to the physical plant at the Chevrolet Flint Motor Plant. In addition to details regarding the plant modifications, the 5-step program used to improve communications and quality is reviewed. Means of improving tool-change setup are also reviewed. All efforts at the Chevrolet Flint Motor Plant are made to improve the number of turns which will increase profits.