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The cost of human natural language translation of Service Information, Assembly Instructions, Training Materials, Operator Manuals and other similar documents is a major expense for manufacturers. One translation avoidance method involves replacing most of a document’s text with still and/or animated graphics. While the graphics with minimum text concept has savings potential, clarity of communication must be maintained for widespread application of this technique. The necessary clarity should be achieved if standards are established for the symbols and graphical conventions used. This paper provides an example of a repair procedure documented using the graphics with minimum text paradigm, describes many of the anticipated standards and provides an update on the progress towards achieving a standard development project.

For many suppliers in the aerospace value chain, business commences when the customer shares the Technical Data Package (TDP) that defines the detailed requirements for a specific part. To convert the customer TDP into the necessary internal documentation, suppliers must expend large amounts of effort. This generally involves passing along copies of the TDP to each functional discipline, which not only results in redundant and laborious work, but it introduces technical risk. There are now software tools available that enable an intelligent TDP that provides more value than just sharing a 3D CAD model. These tools electronically organize and integrate all elements of the TDP independent of the PLM software in use. The application of the intelligent TDP has enabled a 30% reduction in supply chain inefficiencies.

In this paper, experimental investigation on spray atomization and droplet dynamics inside a thermostatic expansion valve (TXV), a component commonly used in vehicle refrigeration system, was conducted. A needle and an orifice were copied from a commercial TXV and machined to be mounted inside a chamber with optical access so that the flow inside the TXV is simulated and visualized at the same time. The break-up and atomization of the refrigerant were documented near the downstream of the orifice under different feed conditions for two TXV with different geometry. A Phase Doppler Anemometry (PDA) system was used later to measure the size and velocity of atomized refrigerant droplets. The results showed that the droplet size variation along the radial direction is slightly decreased at near downstream and increased at farther downstream due to the coalescence.

Vehicle target setting is an evolving process based on continually changing internal (management, standards) and external (competitive and legal) requirements. In addition to evolving requirements, the process for establishing and documenting targets may not be clear. The objective of this paper is to detail the overall process of target setting, the critical factors to consider, and key definitions for each stage of the process. It will describe the complete process from early competitive benchmarking to final verification testing. Setting targets for a vehicle requires definition and thorough benchmarking of the competition, an understanding of the key attributes used to describe the vehicles' performance, and a clearly defined set of requirements. These requirements will be regulatory, corporate and competitively based and grouped by clearly defined, customer perceived attributes which can be cascaded to specific vehicle systems.

Facing a competitive and globalized market and with increasingly demanding customers, companies must constantly seek the development of practices in the development of new products. One of the current practices is the adoption of modularity. In that sense, the objective of this paper is to conduct an analysis of this practice in a Brazilian company, which manufactures agricultural machinery. The applicability of modular design in current products is focused. Therefore, a case study approach has been chosen. First, a review of the scientific literature was conducted, followed by field research, for collecting data based on interviews with product engineers and technical documentation. The case study shows the applicability of the modular design concept in a combine header, by increasing the number of repeated components. The modular header approach facilitates the implementation of engineering changes and allows greater standardization of components.

The beneficial effects of contact disruption in modulation-assisted machining of aerospace alloys have been well documented, but sources for such improvements are not well understood. This study explores the underlying nature of differences that occur in energy dissipation during conventional and modulation-assisted machining by characterizing the relationship between controllable process parameters and their effects on chip formation. Simultaneous in situ force and tool position measurements are used to show that the forces in modulation-assisted machining can be described by empirical force models in conventional machining conditions. These models are found to accurately describe plastic dissipation over a range of modulation conditions and configurations, including in cases where energy expenditure decreases with the application of modulation. These observations suggest that the underlying response in modulation-assisted machining is analogous to that of conventional machining.

The Automated Fiber Placement (AFP) machine layup run time in large scale AFP layup cells consumes approximately 30% of the entire part build time. Consequentially, further reductions to the run time of the AFP machine part programs result in small improvements to the overall cycle time. This document discusses how Electroimpact's integrated system and cell design reduces the overall cycle time by reducing the time spent on non-machine processes.

With the increasing popularity of seamless gear changing and smooth driving experience along with the need for high fuel efficiency, transmission system development has rapidly increased in complexity. So too has transmission control software while quality requirements are high and time-to-market is short. As a result, extensive testing and documentation along with quick and efficient development methods are required. FEV responds to these challenges by developing and integrating a transmission software product line with an automated verification and validation process according to the concept of Continuous Integration (CI). Hence, the following paper outlines a software architecture called “PERSIST” where complexity is reduced by a modular architecture approach. Additionally, modularity enables testability and tracking of quality defects to their root cause.

Psychoacoustics parameters are widely employed in automotive field for objective evaluation of Sound Quality (SQ) of vehicle cabins and their components. The standard approach relies on binaural recordings from which numerical values and curves are calculated. In addition, head-locked binaural listening playback can be performed. The Virtual Reality (VR) technology recently started to diffuse also in automotive field, bringing new possibilities for enhanced and immersive listening sessions, thanks to the usage of massive microphone arrays instead of binaural microphones. In this paper, we combine both solutions: the principal SQ parameters are derived from multichannel recordings. This allows computing a map of direction-dependent values of SQ parameters. The acquisition system consists in a spherical microphone array with 32 capsules and a multiple-lens camera for capturing a panoramic equirectangular background image.

In this work, the effects of the addition of biofuels belonging to different chemical families on the oxidation stability of a conventional fuel surrogate (n-decane) have been investigated. Experiments have been performed in a PetroOxy apparatus, which is one of the references Rapid Small Scale Oxidation Test of the ASTM 7545 methods. When the pressure in the cell of the device decreases by 10% of the maximum pressure recorded, the time measured to reach this target value defines the Induction Period (IP). IP constitutes a quantitative measure of the oxidation stability of the fuel. In addition to the IP measurements for each biofuel / hydrocarbon fuel blend, organic peroxides produced in the liquid sample were quantified at the IP, using iodometric titration and ultraviolet-visible spectrophotometry. Different oxygenated biofuels have been studied in this work: diethyl ether, n-butanol, and cyclopentanone.

Laminar burning velocity is a fundamental measurement describing how a flame propagates into quiescent unburned mixture ahead of the flame at a specified pressure and temperature. Laminar burning velocity of bio-diesel air mixture has been studied in a spherical bomb, using the pressure - time records. Initial pressure, temperature is varied to cover a range from 1 bar - 4 bar and 443K-523K respectively. The range of measurements covered the equivalence ratio from 0.8 to 1.2. Pressure-time records have been used to calculate the flame velocity, burned gas fraction, flame position etc., using a simplified, two zone thermodynamic model, assuming equilibrium composition and homogenous mixture for the burned gases. It is also assumed frozen composition and isentropic compression for the unburned mixture.

Since the amount of dissolved gas in fuels is an important quantity for the description of aeration in injection nozzles, this paper presents Bunsen absorption coefficients for different conventional and bio-hybrid fuels and their effect on nozzle flow phenomena. Bio-hybrid fuels can be produced both on the basis of biomass and with the help of regeneratively generated electrical energy. In contrast to previous work, the Bunsen coefficient was determined for a wide pressure range from approximately 10 MPa to 32.5 MPa. In fact, some of the fuels considered here were never before objects of investigation in terms of their solubility properties. In this work, large differences regarding the Bunsen absorption coefficient between a conventional fuel and a bio-hybrid fuel were observed. For determining the solubility of the fuels, a manometric-volumetric method was used.

Fault-tolerance in commercial aircraft applications is typically achieved by redundancy. In such redundant systems the primary component is checked before the start of a flight to see if it operates correctly. The aircraft will not take off unless the primary is functioning. Airplane manufacturers must certify the airplane systems to be safe for flight. One means of safety certification is by safety analysis which shows that the probability of failure in a typical flight is bounded. The probability bound requirement for a system is based on the criticality of system failure. Usually backup components are checked at intervals that span multiple flights. The first backup may be checked more frequently than the second or higher levels. This leads to flights where the system may have latent faults in the backup components. The probability of failure in such cases varies from flight to flight due to the different exposure times for components in the system.

The introduction of ISO 26262 concepts has brought important changes in the software development process for automotive software. While making the process more robust by introducing various additional methods of verification and validation, there has been a substantial increase in the development time. Thus, test automation and front loading approaches have become important to meet product timelines and quality. This paper proposes automated testing methods using formal analysis tools like Simulink Design Verifier™ (SLDV) for boundary value testing and interface testing to address the demands of ISO 26262 concepts at unit and component level. In addition, the method of automated boundary value testing proposed differs from the traditional methods and the authors offer an argument as to why the traditional boundary value testing is not required at unit (function) level. There are two aspects of the proposed method: automated test case generation and automated test case execution.

The US Army operates in many harsh and demanding environments throughout the world, which are highly corrosive. However, there lacks a basic understanding of the severity of these environments and their impact on the Army's materiel. To better understand this impact and broaden their database of information, the Army has established test sites on the Hawaii islands. These sites represent various climatic conditions the Army operates in. In these locations panel exposure of Army and automotive systems have been made to compare performance with that documented in the continental US by the SAE ACAP and past Army programs. Recently the first set of samples exposed have completed three (3) years of exposure. A secondary set has reached its first year of exposure and a third set have completed three (3) months of exposure. This paper will present a summary of the three year results and future work to be completed.

For some years, OEMs and suppliers have been using CAD tools to improve efficiencies in both mechanical design and electrical design. Modern CAD tools have evolved from simple drafting and documentation towards specialized tools for each task – mechanical layout, mechanical styling, electrical design, manufacturing design, and so on. There is often a significant overlap between the data-scope of each of these tools, but, without good integration facilities, engineers must re-key the same information in each of the different tools: this is both time-consuming and error-prone. This paper examines, and illustrates, the issues, technologies and processes that are available to improve the integration between mechanical and electrical CAD tools, and between OEMs and their suppliers.

Many aerospace & defense organizations have placed an increased emphasis on reducing the time to transition products from engineering to manufacturing while simultaneously reducing the product technical risks. One area with the greatest impact on these objectives is detailed design. This is the stage in the product development lifecycle when the development team addresses the detailed product definition and “Design for Six Sigma”. Unfortunately, most aerospace & defense manufacturers still follow a serial process for creating the detailed design. In addition, producibility is often not formally addressed because it is treated as an additional step that requires extra engineering effort that delays completion of the product definition. This paper presents a solution piloted at Aerojet for the detailed design and manufacture of missile propulsion systems.

The energy dissipated by the fracture of wooden utility poles during vehicle impacts is not currently well documented, is dependent upon non-homogenous timber characteristics, and can therefore be difficult to quantify. While there is significant literature regarding the static and quasi-static properties of wood as a building material, there is a narrow body of literature regarding the viscoelastic properties of timber used for utility poles. Although some theoretical and small-scale testing research has been published, full-scale testing has not been conducted for the purpose of studying the vehicle-pole interaction during impacts. The parameters that define the severity of the impact include the acceleration profile, vehicle velocity change, and energy dissipation. Seven full-scale crash tests were conducted at Exponent's Arizona test facility utilizing both moving deformable and non-deformable barriers into new wooden utility poles.

Classic problems of functional software test development industry include often poorly documented coverage of specification requirements, challenging delivery cycles, high software quality requirements, costly test development, inflexible test sets, and high maintenance costs due to ever changing requirements. Technology and commercial software exist today that can help to resolve all of these issues by automating test design with model-based testing (MBT), i.e., by automatically generating tests and test documentation. In numerous case studies over a wide range of application areas MBT has been independently confirmed [9, 10] to cut testing costs significantly by increasing productivity, to enable of up to 91% code coverage during test execution [8], and to locate numerous defects that have escaped in conventional testing approaches.

Effective requirements elicitation and management is a common need in supplier-OEM relationships, and continues to play a vital role in all aspects of the product development lifecycle. While traditional methods address the business goals for requirements and provide guidance in ensuring the accuracy of the “Descriptive-Prescriptive-Explanatory” outputs for requirements gathering and documentation, engineering organizations continue to encounter challenges with respect to capturing and communicating change, accommodating the addition of relevant design details and efficient propagation to inform development. These challenges become more difficult to overcome in mechatronic systems, which combine mechanical systems with integrated software. As software development can produce an overwhelming volume of information that requires accurate tracking and proliferation, it cannot be effectively managed using traditional hardware-centric systems.