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Viewing 1 to 30 of 14434
2010-04-12
Journal Article
2010-01-0393
Baeyoung Kim, Hyunjun Kim, YoungTak Son, Hae-ryong Kim, Haekyung Kim, Myung-Won Suh
The noise of interior plastic parts has been one of the major driving factors in the design of automotive interior assemblies. This phenomenon is one of the major contributors to the perceived quality in a vehicle. The noise is caused by interior plastic parts and other parts as a result of permanent deformation. Traditionally, noise issues have been identified and rectified through extensive hardware testing. However, to reduce the product development cycle and minimize the number of costly hardware builds, hardware testing must rely on engineering analysis and upfront simulation in the design cycle. In this paper, an analytical study to reduce permanent deformation in a cockpit module is presented. The analytical investigation utilizes a novel and practical methodology, which is implemented through the software tools, ABAQUS and iSight, for the identification and minimization of permanent deformation.
2004-09-21
Technical Paper
2004-01-2808
Gunther Wellmann, Olaf Gedrat, Holger Mayländer
Abstract This technical paper addresses key advances in Flap (High Lift Device) manufacturing technology at the Airbus facility in Bremen, Germany from 1999 to 2004. Strategic manufacturing requirements leading to automated assembly procedures are described, establishing the core of High-Lift Device work flow.
2004-09-21
Technical Paper
2004-01-2807
Peter Zieve, Todd Rudberg, Peter Vogeli, Andrew Smith, Ian Moore
The A380 aircraft is the largest passenger aircraft ever built and an appropriate machine was required to accomplish the fastening of the wing plank to stringer and buttstrap joints. The lower wing panels are curved along the length and move 1.42m out of plane. All previous E4000 machines had clampup heads that would extend and retract whatever distance was required to contact the wing panel. To improve toolpoint alignment, Electroimpact added a Z-axis that moves the yoke in order to reduce the necessary travel envelope of the clamp table axes and to cause them to clamp in the same plane regardless of panel position along the Z-axis.
2004-09-21
Technical Paper
2004-01-2814
Richard Lindqvist, Henrik Kihlman
This paper deals with issues about Orbital drilling implementation and evaluation. The paper summarizes and includes the so far written papers about Orbital drilling. In a previous paper, a conclusion was made, orbital drilling is a suitable method for drilling high quality holes in the specific space application that was studied. The conclusion for further development was then to look more specifically into the process development, i.e. cutting parameters, new cutters, new coatings on cutters etc. Then the investigation and feasibility study started. The project went from early prestudy to fully implemented industrialized solution of the PODU at SAAB Ericsson Space (SES) in Linköping, Sweden. More detailed description on how the project did it is explained in the paper. The early conclusions made after pre- and final acceptance tests of the PODU at SES shows that Orbital drilling is a comprehensive method compared to conventionally drilling methods.
2004-09-21
Technical Paper
2004-01-2813
Sylvain Guérin, Raymond P. LeCann
Handheld Automation may appear to be a contradiction in terms. It is not. A wide range of assembly methodologies are currently employed in support of aircraft assembly, two very specific approaches predominate. 1 The most popular approach, which accounts for the majority of the fasteners installed in current production aircraft, consists of a manual process. This requires the operator to perform manual operations in each of the many, if not all, of the steps involved in installing fasteners. Steps include fastener selection, sealant application, fastener insertion, fastener deformation, pin extraction, collar application, or torqueing, as the fastener may require. 2 The other end of the spectrum involves total automation where all of the steps are performed by a machine, with little or no manual involvement by the operator, other than supervision. Handheld automation bridges the gap between these extremes.
2014-04-01
Journal Article
2014-01-1018
Robert V. Petrach, David Schall, Qian Zou, Gary Barber, Randy Gu, Laila Guessous
Coatings have the potential to improve bearing tribological performance. However, every coating application process and material combination may create different residual stresses and coating microstructures, and their effect on bearing fatigue and wear performance is unclear. The aim of this work is to investigate coating induced residual stress effects on bearing failure indicators using a microstructural contact mechanics (MSCM) finite element (FE) model. The MSCM FE model consists of a two-dimensional FE model of a coated bearing surface under sliding contact where individual grains are represented by FE domains. Interactions between FE domains are represented using contact element pairs. Unique to this layered rolling contact FE model is the use of polycrystalline material models to represent realistic bearing and coating microstructural behavior. The MSCM FE model was compared to a second non-microstructural contact mechanics (non-MSCM) model.
1999-10-06
Technical Paper
1999-01-3448
John Perrelli
Gemcor has pioneered the research, development, and implementation of Electronic Servo Controlled Roller Screw Technology (ESCRST) since 1995. This roller screw technology can replace servo hydraulics in a variety of applications while still achieving the patented Drivmatic® Squeeze and Squeeze/Squeeze III riveting processes.
1999-10-06
Technical Paper
1999-01-3447
Ali Salour, James Cunov
This paper covers issues related to the installation, testing, and production implementation of a large-scale automated wing drilling/fastener installation system. Emphasis is placed on describing the production process, foundation requirements, axes alignment, calibration, testing and implementation. Description will include key hardware features such as the multi-function end effector and spindle end effector. The objective is to convey the complexity of implementing this system as well as reviewing the lessons learned from this experience.
1999-10-06
Technical Paper
1999-01-3444
Daniel S. Alcombright, Wm. Todd Bedwell
The Fastener Delivery System (FDS) provides a new and unique method to automatically feed fasteners. The FDS is a compact automated system that conveys fasteners on demand to a user-supplied end effecter. The system may consist of up to six basic elements: a drum, a drum positioning system, a fastener lifting assembly, an escapement head, a jib crane, and a computer control system. Systems are currently in use at Boeing’s Advanced Manufacturing Center in St. Louis, Missouri for the automated assembly of the F/A-18E Super Hornet. Each system can store over 8000 fasteners of 400 different varieties. Rivets, slave bolts, and threaded fasteners are conveyed on demand in non-sequential order with no changeover. Fastener dimensions range from head diameters of 4mm to 22mm and lengths from 6mm to 58mm. The fasteners are stored in tubes, which are arranged in a high-density, radial pattern in precision machined covered drums. The drums act as “mini-warehouses”.
1999-10-06
Technical Paper
1999-01-3450
Blake Stancik, Carter Boad
This paper details the Electroimpact Cartridge Feed Auto Select (CFAS) System, the Electroimpact Cartridge Filling Station (CFS) and the implementation of these systems on today&’s factory floors. Problems inherent in handling tens of thousands of fasteners per workpiece have traditionally been an Achilles Heel to many aerospace-manufacturing cells. The CFAS system moves the job of sorting through bulk fasteners to the stand alone offline CFS. With the bulk feeding process offline, problems such as contaminated fastener lots get taken care of before they ever get to a fastening machine. Modular briefcase sized coiled tube magazines store and distribute fasteners to automated riveting and bolting equipment via the CFAS rack. Cartridges captively hold 500 to 3,000 fasteners from 1/8” to 3/8” diameters and are length independent which allow a small number of cartridges to work with a large array of overall fasteners.
1999-10-06
Technical Paper
1999-01-3449
Julie. R Jones, Stuart R. Seley, John E. Inman
The standardization of fastening systems utilized in military and commercial aircraft vehicles supports the primary focus of IRAD 7-928 which is to develop and implement aircraft manufacturing technologies and processes best suited for affordability. Swaging lockbolt collars on threaded pins was initiated by St. Louis Phantom Works in August 1997 on the Electromagnetic Riveter (EMR) AFAS Test Bench. The goal of this concept is to develop a robust fastening system which combines the lower panstock cost elements of existing Hi-Lok and Lockbolt hardware.
1999-12-01
Technical Paper
1999-01-3072
Roberto Garcia, José Barboza
General Motors Corporation has always made every effort so that our end products and processes and configuration of components could help preserve the environment. Along those lines, General Motors do Brasil started to develop a protective coating that is corrosion resistant and environment friendly. At first, this will be used for fasteners. This effort involves dramatic changes in attitude, such as our need to admit that we are responsible for managing resources and keeping our world habitable and healthy for the future generations. This study describes metallic and organometallic coatings with an increased resistance to corrosion associated to temperature, free of such harmful metals as cadmium, nickel, lead, chromium, etc. Also demonstrated here is the significance of the total friction coefficient and its composition, considering the friction coefficients inherent to the fastener threads/heads.
1999-10-19
Technical Paper
1999-01-5544
Thomas M. Leard
A multifunction display provides the flight crew with access to a mix of information. The challenge for the crew, the designer, and the certification agencies, is to determine if the human interface to this mix can be understood under normal and abnormal conditions. The technical capabilities of signal processing and displays permit endless information combinations to exist. However, human performance and mental processing capabilities impose significant challenges in designing the display and controller interface. For the crews to be successful, they ultimately need to obtain an increase in their level of situational knowledge from the flow of information that a multifunction display provides.
2011-10-18
Technical Paper
2011-01-2599
Kevin Donahue
The aerospace industry has long sought a solution for storing maintenance history information directly on aircraft parts. In 2005 leading airframe manufacturers determined that passive Radio Frequency Identification (RFID) technology presented a unique opportunity to address this industry need. Through the efforts of the Air Transport Association (ATA) RFID on Parts Committee and SAE International testing standards and data specifications are in place to support the broad adoption of passive RFID for storing parts history information directly on aircraft parts. The primary focus of the paper will be on the SAE AS-5678 environmental testing standard for passive RFID tags intended for aircraft use. Detail will be provided to help aerospace manufacturers understand their role and responsibilities for current programs and understand how this may impact their parts certification process.
2011-10-18
Technical Paper
2011-01-2598
George Nicholas Bullen, Tim Shinbara
Probabilistic methods are used in calculating composite part design factors for, and are intended to conservatively compensate for worst case impact to composite parts used on space and aerospace vehicles. The current method to investigate impact damage of composite parts is visual based upon observation of an indentation. A more reliable and accurate determinant of impact damage is to measure impact energy. RF impact sensors can be used to gather data to establish an impact damage benchmark for deterministic design criteria that will reduce material applied to composite parts to compensate for uncertainties resulting from observed impact damage. Once the benchmark has been established, RF impact sensors will be applied to composite parts throughout their lifecycle to alert and identify the location of impact damage that exceeds the maximum established benchmark for impact.
2011-10-04
Technical Paper
2011-36-0222
Luiz Gustavo Campos, Maurício V. Correa, José A. G. Simões
The automotive industry demands for quality and technological innovations that enhance the performance of their products. Visual quality and corrosion resistance are also very important, even for fasteners exposed to the weathering throughout its life cycle that shall meet the performance requirements specified by the automotive industry. This paper shows how the search for new technologies leads to innovations in the already established surface treatment with a new generation of sealers for the automotive industry. This brand new technology of organic/polymeric sealer applies in water basis a single and uniform layer with low molecular weight (1000 to 10000 Dalton) in order to enhance specific properties such as high corrosion resistance, low coefficient of friction attributing characteristics of self-lubricating surface and increase in the wear resistance of the coating.
2010-10-06
Technical Paper
2010-36-0472
Paulo Cesar Sigoli, Mauro Moraes De Souza, Juliano Savoy, Eric Hideki Okamoto Noguchi, Guilherme Natali Della Valentina
The effective length of screwed fasteners, regarding its correlation between safety assembling and production issues, has always been an open question for designers of fastening system. This work presents a real case of dimensioning one wheel nut according to theoretical and practical tests in order to guarantee a safe assembling. The objective of this study is to validate the geometric dimensioning of metric threads and their applications under real conditions.
2011-06-13
Technical Paper
2011-38-0079
Daniel C. Knezevici, Dan Fuleki, James MacLeod
This paper describes the commissioning of a linear compressor cascade rig for ice crystal research. The rig is located in an altitude chamber so the test section stagnation pressure, temperature and Mach number can be varied independently. The facility is open-circuit which eliminates the possibility of recirculating ice crystals reentering the test section and modifying the median mass diameter and total water content in time. As this is an innovative facility, the operating procedures and instrumentation used are discussed. Sample flow quality data are presented showing the distribution of velocity, temperature, turbulence intensity and ice water concentration in the test section. The control and repeatability of experimental parameters is also discussed.
2012-10-02
Technical Paper
2012-36-0195
Reinaldo dos Santos, Masoud Saadat, Santosh Neriya, David Popejoy, Valter E. Beal
NVH requirements are critical in new driveline developments. Failure modes due to resonances must be carefully analyzed and potential root causes must have adequate countermeasures. One of the most common root causes is the modal alignment. This work shows the steps to design and optimize a new plastic bracket for an automotive half shaft bearing. This bracket replaces a very stiff bracket, made of cast iron. The initial design of plastic bracket was not stiff enough to bring natural frequency of the system above engine second order excitation at maximum speed. The complete power pack was modeled and NVH CAE analysis was performed. The CAE outputs included Driving Point Response, Frequency Response Function and Modal analysis. The boundary conditions were discussed deep in detail to make sure the models represented actual system.
2012-10-02
Technical Paper
2012-36-0244
Henrique Martinni Ramos de Oliveira, Estephanie Nobre Dantas Grassi, Pedro Augusto Sobral Espindola, Carlos Jose de Araujo
Shape memory alloys (SMA) have a unique behavior due to a reversible phase transformation between two solid crystalline structures: martensite (low temperature and low stiffness phase) and austenite (high temperature and a higher stiffness phase). This transformation can occur either as a result of temperature change or mechanical stress load, both above characteristic critical values of these materials. Due to the reversible nature of this phenomenon, direct transformation occurs when austenite transforms into martensite and reverse transformation when martensite transforms into austenite. The latter is induced by raising the temperature and it is this process that occurs during the generation of significant associated forces through the undergone deformation recovering of the material, being of fundamental importance for the use as actuators.
2017-01-10
Technical Paper
2017-26-0279
Onkar P Bhise, S Ravishankar
Abstract Polytetrafluoroethylene (PTFE) is used extensively as the inner tube material in various Aerospace and Industrial hose constructs. The fluoropolymer exhibits various unique mechanical properties from other fluoropolymers including chemical inertness, non-adhesiveness and low friction coefficient making it an attractive solution for hose applications. PTFE material can be modeled using various material modeling approaches including linear-elastic, hyperelastic and viscoplastic depending on the level of accuracy required in predicting material response. Fluoropolymers, like PTFE, are considered viscoelastic-viscoplastic materials. In other words, the material exhibits both viscous and elastic characteristics when undergoing deformation but also possesses behavior in which the deformation of the material also depends on the rate by which loads are applied.
2014-04-20
Journal Article
2014-01-9098
Ala Qattawi, Mahmoud Abdelhamid, Ahmad Mayyas, Mohammed Omar
1 The manufacturing of Origami based sheet metal products is a promising technology, mostly in terms of reducing the tooling and process complexity. This procedure can also be called fold forming, as it depends on exclusively shaping the required geometry via sequence of bends. However, the design analysis and modeling of folded sheet metal products are not fully mature, especially in terms of determining the best approach for transferring the analysis from a three-dimensional (3D) to a two-dimensional (2D) context. This manuscript discusses the extension of the Origami technique to the fold forming of sheet metal products represented in modeling approach and design considerations for the topological variations, the geometrical validity, and the variance of stress-based performance. This paper also details the optimization metrics that were developed to reflect the design and manufacturing differences among the possible topological and geometrical options for a single part design.
2014-09-16
Technical Paper
2014-01-2263
Eric Barton, Dan Hasley, Joey Jackson
Abstract The following is a unique case study expounding on automatic fastening technology designed and engineered to ramp up a Tier 2 supplier that had no experience with automatic fastening, to efficiently produce a large volume of fuselage panel assemblies with demanding process requirements in a very short amount of time. The automation technology integrated for the skin to stringer & skin to window frame fastening were two GEMCOR G12 five-axis CNC All-Electric fastening systems coupled with a Cenit offline part programming system. This joint solution served as a launch vehicle for Center Industries to efficiently supply the full rate of fuselage panel assemblies for a large volume commercial aircraft program without having any automatic riveting experience.
1955-01-01
Technical Paper
550184
ALFRED J. GARDNER
1956-01-01
Technical Paper
560286
W. A. GEBHARDT, R. BODEMULLER
The control of compressor stall and surge is one of the most difficult problems confronting the control engineer today. Three modes of stall control are presented: (1) the scheduling, or open loop, control now in use on most gas turbine engines, (2) the closed loop control using compressor parameters which synthesize the stall boundary, and (3) the closed loop control using an incipient stall ‘sensor’. The use of a closed loop control which uses synthesizing stall parameters may partially solve some of the present problems, such as variations in physical properties of fuel. However, there is a great incentive to develop a means for detecting incipient stall and surge in order to aid in reducing the development time for future supersonic, high altitude gas turbine engines.
1956-01-01
Technical Paper
560249
E. J. Eckert
1956-01-01
Technical Paper
560095
R. R. BERLOT
1958-01-01
Technical Paper
580062
U. H. von Glahn, J. H. Povolny
THE performance characteristics of various devices applicable for jet directional control, lift augmentation, and VTOL-STOL studied at the NACA Lewis Laboratory are discussed, including jet deflection devices applicable to the conventonal round nozzle and novel nozzle configurations. The results indicate that many of the deflection devices applicable to conventional nozzles can readily be used for directional control or lift augmentation. Other deflection devices, such as movable plug, internal flap, cylindrical thrust reverser, swiveled primary with fixed shroud, and 90 deg side-bleed nozzle, are limited in application to jet directional control or aircraft trim because the loss in axial thrust for a given deflection force is prohibitive or the maximum deflected force obtainable is limited.
1959-01-01
Technical Paper
590243
F. H. POLLARD
Viewing 1 to 30 of 14434

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