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United States automotive manufacturers, to maintain their pre-eminent position in world motor vehicle production, must expand their operations overseas. Tooling amortization expenses for the highly sophisticated domestic models are exorbitant because of low production volumes overseas. Therefore, it has been desirable to develop a vehicle which can be easily manufactured overseas for minimum capital expenditures. Chrysler International’s XLV truck cab has been styled, designed, and processed for low volume production overseas. This paper deals with the XLV program -- from the original idea to production in Turkey.

The development of the XB-70 research aircraft produced advancements in many fields of technology. This paper covers a few of these advancements in the areas of materials, equipment, and manufacturing. These include honeycomb construction, PH 15-7 alloy steel, vacuum melted H-11 steel, equipment capable of withstanding high temperatures, chemical milling of many different alloys, miniaturized welding equipment, and exothermic brazing techniques.

Planning for ground servicing and maintenance started in the proposal phase and has been followed by test program experience with the XB-70 Mach 3 air vehicle. Servicing and associated safety requirements are summarized. Discussion of maintenance and support actions includes mention of equipment provided to meet the requirements. Preflight, postflight, and periodic operations are outlined, along with some indication of changes that resulted when plans were put into practice. The demands of a high performance flight test air vehicle limit movements toward simplification.

THE X-ray spectrum readily adapts itself to problems in chemical analysis and crystal formation. It is effective on very minute particles which otherwise cannot be segregated. A permanent record is made, and the specimens may be used over and over again, as the X-ray is non-destructive. As a means of inspection, X-ray clearly shows the interior of objects such as weldings castings, forgings, cold-worked metals, and so on. Inhomogeneities that are very slight in width and a fraction of one per cent in thickness are seen easily on a radiograph. Defects thus found may be eliminated summarily by checking various steps in production.

With X-ray stress and fine structure analyses, results have been obtained that are inconsistent with present views of the structure and tempering kinetics of hardened steels. Experimental results are reported, and an attempt is made to establish a model of the tempering kinetics of hardened steels. It is shown that the Snoek and Cottrell effects are the dominating mechanisms of diffusion and that they lead to the formation of two α phases of differing carbon content; the phase with the accumulated carbon finally results in the formation of cementite.

A non-destructive x-ray technique, the double crystal diffractometer method, is presented as a tool to investigate the aging and deformation behavior of the Al-Li alloy. This is a sensitive method for measuring the strain and dislocation density within individual grains through the x-ray rocking curve. In addition, models were developed to describe the aging and deformation characteristics of this alloy.

The salient features of modern gasoline direct injection include cavitation, flash boiling, and plume/plume interaction, depending on the operating conditions. These complex phenomena make the prediction of the spray behavior particularly difficult. The present investigation combines mass-based experimental diagnostics with an advanced, in-house modeling capability in order to provide a multi-faceted study of the Engine Combustion Network’s Spray G injector. First, x-ray tomography is used to distinguish the actual injector geometry from the nominal geometry used in past works. The actual geometry is used as the basis of multidimensional CFD simulations which are compared to x-ray radiography measurements for validation under cold conditions. The influence of nozzle diameter and corner radius are of particular interest. Next, the model is used to simulate flash-boiling conditions, in order to understand how the cold flow behavior corresponds to flashing performance.

Residual stress and hardness in steel due to thermal, mechanical, and fatigue deformations are determined by an X-ray diffraction method. The sharp temperature rise associated with electrical discharge machining causes austenitizing, rehardening, and tempering, and results in high tensile residual stress. Shot-peening quality is evaluated from residual stress and hardness induced by the peening. Rolling contact fatigue of carburized and hardened bearings causes a transformation of austenite to martensite, and thereby generates more residual compression, and also causes permanent fatigue softening. Less softening is observed in inner races of consutrode and cross-forged steels than in air-melted steel, and the former steels exhibit greater fatigue life at early and mean failure levels.

X-ray is an indispensable aid in locating and determining the extent of incipient failures in structure which is inaccessible by position or covered by multiple layers of metal. It is also the most feasible method for checking oil coolers for contamination; bonded honeycomb panels for water; fuel lines for erosion; and with a 360 deg emission tube, fuselage frames for structural integrity without removing the interior upholstery and panels from the passenger compartment or cargo compartments.

Automotive structural components are exposed to high loads, impact situations and corrosion. In addition, there may be temperature excursions that introduce creep as well as reduced modulus (stiffness). These issues have limited the use of light metals in automotive structural applications primarily to aluminum alloys, and primarily to cast wheels and knuckles (only a few of which are forged), cast brake calipers, and cast control arms. This paper reports on research performed at Chongqing University, Chongqing China, under the auspices of General Motors engineering and directed by the first author, to develop a protocol that uses wrought magnesium in control arms. The goal was to produce a chassis part that could provide the same engineering function as current cast aluminum applications; and since magnesium is 33% less dense than aluminum, would be lighter.

The wide variety of available leadless electronic components is described. Some typical applications of these devices are illustrated. The advantages to be gained through the use of these surface mounted devices are explained. These include reduced size, increased reliability, improved performance and reduced cost. Methods of application, including automatic assembly equipment, are discussed. Several applicable soldering processes are explained.

This paper will discuss Concurrent Engineering as an emerging product development methodology. Specific emphasis will be placed on some of the key tools and considerations necessary for the success of Concurrent Engineering. In particular, the paper will discuss strategic product planning driven by customer requirements and how the product development effort will support the strategic product plan.

Cockpits have changed dramatically over the last ten years. The electro-mechanical instruments have largely been replaced with electro-optical controls and displays. This change in the pilot-vehicle interface, coupled with a second development, the emergence of a very powerful airborne computer system, an Electronic Crewmember, has had a significant impact on workload in the cockpit. Workload has shifted from physical to mental, and many workload measurement tools applied previously may no longer be appropriate. This paper discusses the prediction, real time measurement and dynamic allocation of cockpit workload in an aircraft with a crew of two -- one human and one electronic.

One of the most unsolved problems in space projects, where human beings are involved, is the impossibility of simulating on the ground the effects of microgravity on astronauts' operability in space. [1] In particular, this is traceable in the performance of work activities, such as performing physiological scientific experiments. [2] This paper focuses on a study of the gap between the two operational scenarios: the ground test simulation and the in-flight space performance of complex physiological experiments. The major differences between the two operational scenarios are highlighted, and recommendations for improvement are suggested. The main finding of this paper is that, in order to make experiment performance not only possible but also easy and efficient, it is necessary to consider all human factors involved. With this perspective, the author's aim has been to find an effective way to consider all human factors of the ground and space operational conditions.

Work solenoids are widely used in household appliances. The environment and design of this type application does not lead to solenoids for the earthmoving industry. This paper presents the environmental effects to be considered when designing a solenoid for the earthmoving industry. It further explains the need for, and type of, test necessary to validate the design. Finally a review of production quality procedures, necessary to insure reliable production parts is discussed.

A bioregenerative diet is characterized by a high proportion of foods produced on site. The production and processing of foods into either ingredients or recipes entails certain labor requirements. Ideally these labor requirements should be estimated with a high degree of accuracy. Crew time is at premium and any amount of time spent on food preparation and processing is time not spent in conducting research and any other activities devised to improve the quality of life of the astronauts. Moreover, a wide variety of tasks are involved in the food preparation of a bioregenerative diet and the labor times of these tasks do not scale or increase in uniform fashion. Predicting food preparation labor requirements for varying crew sizes will require task specific models and data. Videotape analysis is a work measurement tool used in the manufacturing industry.

The following investigation was carried out to evaluate work hardening and bake hardening in actual body components. Five pressings were made from mild steel and three different grades of high-strength steel with ultimate tensile strengths ranging from 380 to 470 N/mm2. The latter were a batch annealed Rephos steel and two other grades of continuously annealed dual-phase (DP) steel. Tensile test specimens were taken from these components to evaluate the work hardening and bake hardening. The results are contained in the report. A new Volvo standard for high-strength cold-rolled sheet steel has been introduced. To some extent, the formulation of the standard was based on the results of the investigation of work hardening and bake hardening. The form and application of the standard are described in the report.

Two new developments in woodgrain finishing techniques for zinc die cast trim components are revealed which apply the permanent finishes to the casting surface. Product design details and comparative costs of chromium plated ABS and zinc are given for a typical instrument panel trim bezel. Recommended design features and basic pressure sensitive adhesive specifications are discussed which should eliminate adhesive bonding failures for woodgrain appliques used on trim components.

This work is based on a process to develop novel cellulose microfibre reinforced composite materials, and to understand fundamental mechanical properties of these composites. Cellulose microfibres having diameters <1 μm were generated from bleached kraft pulp by a combination of high shear refining and subsequent cryocrushing under liquid nitrogen, followed by filtration through a 60 mesh screen. Through film casting in polyvinyl alcohol, theoretical stiffness of the microfibres was calculated as 69 GPa. Subsequently, these microfibres were successfully dispersed in the bioplastics thermoplastic starch and polylactic acid (PLA), using conventional processing equipments. The high aspect ratio of these microfibres coupled with their high tensile properties imparted superior mechanical strength and stiffness to the composites. These indicated that by suitably choosing the polymer, excellent reinforcement can be achieved for high end applications like automotive parts.

Defining the wireless marketing is a challenge in today's world. Companies interested in capitalizing on the wireless market for automatic vehicle location (AVL) have a number of wireless options from which to choose. One of the most exciting wireless combinations is GPS (Global Positioning System) and cellular systems. The Global Positioning System (GPS)/cellular combination can be used to create Automatic Vehicle Location systems for a wide variety of applications, from fleet management to personal security. Unfortunately, no single wireless network fits all the possible AVL applications, and choosing the best network for an application is essential to system performance. This paper reviews the current wireless technologies available in the market-place, discusses why ATX chose the wireless technology it uses, and gazes into the crystal ball to forecast the future of wireless.