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Technical Paper
2014-10-13
Chunshan Li, Guoying Chen, Changfu Zong
This paper presents a fault-tolerant control (FTC) approach for four-wheel independently driven and steered (4WID/4WIS) electric vehicles. An adaptive control-based passive fault-tolerant controller is designed to improve vehicle safety, performance and maneuverability when an actuator fault happens. The proposed fault tolerant control method consists of the following three parts: 1) a fault detection and diagnosis (FDD) module that monitors vehicle driving condition, detects and diagnoses actuator failures with the inequality constraints ; 2) a motion controller that computes the generalized forces/moments to track the desired vehicle motion using Model Predictive Control (MPC); 3) a reconfigurable control allocator that redistributes the generalized forces/moments to four wheels with equality constrained optimization. The FTC approach is based on the reconfigurable control allocation which reallocates the generalized forces/moments among healthy actuators once the actuator failures is detected.
Technical Paper
2014-09-30
Abhinav Tomar
The major emissions of diesel engines are oxides of nitrogen (NOx), particulate matter (PM), carbon dioxide (CO2), carbon monoxide (CO). Among these emissions, oxides of nitrogen (NOx) and the particulate matter are the reasons of serious concern. The usage of CNG in Dual fuel engine along with pilot diesel injection; the emissions have been decreased drastically. Homogeneous mixing of fuel and air leads to cleaner combustion and lower emissions. As peak temperatures are significantly lower than in typical CI engines, NOx levels are supposed to reduce significantly. The premixed lean mixture reduces soot particles. Dual fuel provides up to a 30% fuel saving, while meeting current emission standards along with higher efficiency and lower NVH levels compared to conventional CI engines within certain range of loads. A methodology using a small pilot quantity of diesel fuel injected during the compression stroke to improve the power density and operation control is carried out for an Dual fuel engine based on a stationary, water cooled truck engine.
Technical Paper
2014-09-30
Giorgio malaguti MD, Carlo Ferraresi, Luca Dariz, Massimiliano Ruggeri
Vehicle complexity is growing due to various factors: new functionalities, functional safety, hybridization, task management, etc. On the other hand both service centers need to up to date their competences and knowledge in newer vehicles, in order to efficiently repair and maintain new vehicles. Finally users of special machines, like military, agricultural, mining vehicles etc, need to be able to recover by faults or even repair the vehicles in critical conditions, in order to maintain the vehicle functionality, even in case of failure occurrence. Complex manuals don't provide the most efficient solution, while Augmented Reality represents a very promising technology both if applied to traditional smart-phones, and if applied to the newly glasses presented to the market. By now, this technology has been adopted mainly for games, and marketing purposes, such as tourist information. Instead, the paper deals with other ways in which AR can be extremely useful: AR has been used for two new topics, fast learning of simple procedures by low-skilled personnel and fault recovery or maintenance in hazardous environments or work places.
Technical Paper
2014-09-30
Mukunda Gopalakrishnan, Frederico Paulo Tischer
With growing concern about emissions of GHG (greenhouse gases) the use of natural gas as fuel has been seen as a very interesting alternative. Natural gas, whose main constituent is methane, due to its higher ratio of hydrogen / carbon and their higher content of energy generates about 22% less carbon dioxide (CO2) emissions compared to diesel considering the same combustion efficiency. To make use of this advantage in commercial vehicles there are many barriers to overcome: efficiency, drivability and legislation are some of them. According to tests conducted so far, the use of natural gas compression ignition (diesel cycle) allows the equivalent efficiency of a diesel engine maintaining the same torque and power curve. Controlling the torque in the dual fuel engine with diesel and CNG is an absolute necessity. This allows not only converting a required driver demand torque into actuator signal but also calculating if a change in operating point of any of the torque controlling factors is needed so that the driver demand can be immediately realized.
Technical Paper
2014-09-16
Karl Strauss
“Today’s electronic components rely on principles of physics and science with no manufacturing precedence and little data on long term stability and reliability.” [1] Yet many are counting on their reliable performance years if not decades into the future, sometimes after being literally abandoned in barns or stored neatly in tightly sealed bags. What makes sense? To toss everything away, or use it as is and hope for the best? Surely there must be a middle ground! This paper discusses a three-phase initiative ultimately leading to the issuance of guidelines on the use of devices that have been subjected to long term storage, including recommended and required re-examinations based on Physics of Failure rather than fear and conjecture that is so prevalent today
Technical Paper
2014-09-16
Marco Amrhein, Jason Wells, Eric Walters, Seana McNeal, Brett Jordan, Peter Lamm
Electrical power system components, such as electrical machines and power electronic converters, face many conditions that can have a detrimental impact on life and reliability [1] and are of a mechanical, electrical, and thermal nature. One specific aspect not discussed in detail in the literature concerning the reliability of such systems is the impact of changing electrical operating conditions (i.e., transient loading) on component life. Besides well-known power quality challenges, dynamic or transient loading in electrical power systems (EPS) can impact individual components connected to the EPS because of secondary effects associated with such transients [2]. Specifically, transient loads can cause additional loss in the electrical conduction path consisting of windings, power electronics devices, distribution wires, etc., particularly when loads introduce high peak vs. average power ratios. Additional loss contributes to heating of components and devices, which in turn decreases the life expectancy of power electronic devices, passive filtering components (capacitors and inductors), and wire and winding insulation systems.
Technical Paper
2014-09-16
Janice Meraglia, Mitchell Miller
As part of a comprehensive counterfeit mitigation effort, the Defense Logistics Agency (DLA) has created a program of four initiatives including the requirement of SigNature DNA marking on microcircuits. The Agency’s efforts began prior to the National Defense Authorization Act of Fiscal Year 2012, Section 818. Also, in the April 26, 2013 memo from Under Secretary Frank Kendall, the Office of Secretary of Defense is clearly focused on “prevention and early warning,” as the “primary” defense against counterfeits. SigNature DNA marking is within the spirit and guidance set forth by both DLA and OSD. Section 818 compels government action and creates real liability for contractors. Among other provisions, Section 818 requires the government and contractors to establish “…policies and procedures to eliminate counterfeit electronic parts from the defense supply chain” and “…mechanisms to enable traceability of parts.” SigNature® DNA provides per part forensic traceability and can be implemented as part of a comprehensive inventory management system.
WIP Standard
2014-07-22
A program, which ensures quality with the relevant standards shall be introduced for all on-line Stations where de-icing/anti-icing of aircraft on the ground is either normally carried out, or where local conditions may periodically lead to a requirement for airplcraft to be de-iced/anti-iced. Deficiencies, in regard to a Station's local de-icing/anti-icing procedures, shall be identified and subsequently actioned through this program, thereby ensuring that the required safety standards are maintained.
WIP Standard
2014-07-22
This standard defines the requirements for fully replacing undesirable surface finishes using solder dip. Requirements for qualifying and testing the refinished piece parts are also included. This standard covers the replacement of pure tin and Pb-free tin alloy finishes with SnPb finishes. This dipping is different from dipping to within some distance of the body for the purposes of solderability; solder dipping for purposes other than full replacement of pure tin and other Pb-free tin alloy finishes are beyond the scope of this document. It covers process and testing requirements for robotic and semi-automatic dipping process but does not cover purely manual dipping processes, due to the lack of understanding of the appropriate requirements for hand-dipping for tin whisker mitigation at this time. This standard does not apply to piece-part manufacturers who build piece parts with a hot solder dip finish. It applies to refinishing performed by any other group, including a third party supplier, production facilities at the supplier and other organizations, whenever the intent of the dipping is to have full coverage and replacement of Pb-free tin.
Standard
2014-07-22
This AS describes a standard method for viscosity measurements of thickened (AMS1428) anti-icing fluids. Fluid manufacturers may publish alternate methods for their fluids. In case of conflicting results between the two methods, the manufacturer method takes precedence. To compare viscosities, exactly the same measurement elements (including spindle and container size) must have been used to obtain those viscosities.
Standard
2014-07-11
This specification covers minimum design and test requirements for aircraft tire inflation-deflation equipment for use on all types of aircraft. It shall be the responsibility of the airframe manufacturer to determine the compatibility of the requirement with the applicable aircraft and to specify requirements in excess of these minimums as necessary.
Standard
2014-07-07
This SAE Aerospace Information Report (AIR) is intended to be used as a process verification guide for evaluating implementation of key factors in repair of metal bond parts or assemblies in a repair shop environment. This guide is to be used in conjunction with a regulatory approved and substantiated repair, and is intended to promote consistency and reliability.
Standard
2014-07-07
This ARP provides insights on how to perform a cost benefit analysis (CBA) to determine the return on investment that would result from implementing an integrated Health Management (HM) system on an air vehicle. The word “integrated” refers to the combination or “roll up” of sub-systems health management tools to create a platform centric system. The document describes the complexity of features that can be considered in the analysis, the different tools and approaches for conducting a CBA and differentiates between military and commercial applications. This document is intended to help those who might not necessarily have a deep technical understanding or familiarity with HM systems but want to either quantify or understand the economic benefits (i.e., the value proposition) that a HM system could provide. Prognostics is a capability within some HM systems that provides an estimation of remaining useful life (RUL) or time to failure and so Prognostic Health Management (PHM) is used where this predictive element exists.
WIP Standard
2014-07-01
The federal government and industry have moved to concurrent acquisition and development processes using integrated process teams (IPTs). These processes are supported by timely, accurate, cross functional access to data within an integrated data environment (IDE) enabled by advances in information technology (IT). Since the advent of acquisition reform in 1994, Data Management (DM) practices have evolved from being directed by a prescriptive set of standards and procedures to use of the guidance in a principles-based standard -- ANSI/EIA 859.

GEIA Handbook 859 provides implementation guidance for ANSI/EIA 859, with discussions of applications of the standard's principles, tools, examples, and case studies. Handbook 859 is organized according to the lifecycle of data management and covers activities from the pre-RFP stage through records disposition. It also provides annexes on topics which apply at multiple stages in the lifecycle, such as protection of data, continuous improvement and knowledge management.

Standard
2014-06-26
This SAE Recommended Practice defines, for vehicle manufacturers and collision information and equipment providers, the types of vehicle dimensional data needed by the collision repair industry and aftermarket equipment modifiers to properly perform high-quality repairs to damaged vehicles. Both bodyframe and unitized vehicles, including passenger cars and light trucks, are addressed.
WIP Standard
2014-06-26
On-Board Diagnostic (OBD) regulations require passenger cars, and light and medium duty trucks, to support communication of a minimum set of diagnostic information to off-board “generic” test equipment. This document specifies the diagnostic data which may be required to be supported by motor vehicles and external test equipment for diagnostic purposes which pertain to motor vehicle emission-related data. SAE J1979 was originally developed to meet U.S. OBD requirements for 1996 and later model year vehicles. ISO 15031 5 was based on SAE J1979 and was intended to combine the U.S. requirements with European OBD requirements for 2000 and later model year vehicles.
WIP Standard
2014-06-24
This document discusses, in broad general terms, typical present instrumentation practice for post-overhaul gas turbine engine testing. Production engine testing and engine development work are outside the scope of this document as they will typically use many more channels of instrumentation, and in most cases will have requirements for measurements that are never made in post-overhaul testing, such as fan airflow measurements, or strain measurements on compressor blades. The specifications for each parameter to be measured, in terms of measurement range and measurement accuracy, are established by the engine manufacturers. Each test cell instrument system should meet or exceed those requirements. Furthermore, each instrument system should be recalibrated regularly, to ensure that it is still performing correctly.
Standard
2014-06-24
This SAE Aerospace Standard (AS) provides requirements for design and installation of aircraft jacking pad adapters and the mating jack socket interface to permit use of standard jacking equipment to be used in civil and military transport aircraft. The adapter defined herein shall be the key interface between the aircraft and the aircraft jack(s).
Standard
2014-06-24
This document establishes the minimum requirements for an environmental test chamber, and test procedures to carry out anti-icing performance tests according to the current materials specification for aircraft deicing/anti-icing fluids. The primary purpose for such a test method is to determine the anti icing endurance under controlled laboratory conditions of AMS1424 Type I and AMS1428 Type II, III, and IV fluids.
Article
2014-06-23
For over 40 years, Alpina has been BMW's 'outside' tuning house. Their CEO explains the synergies behind his company's success.
WIP Standard
2014-06-19
This Bulletin is initially intended to be used to convey a combination of information to CM practitioners, both new and already skilled personnel alike. It provides the "what" of CM products and activities; with the "when" of CM correlated to DoD acquisition phases and milestones – thereby giving a time-phased depiction. The document spreadsheet should be read from top to bottom. It shows both the CM activities and products that should be performed and accomplished on a program or project. Next it provides a brief description of the CM activity or product and a column providing a reference(s) to other sources of information to learn even more about how the activity or product should be accomplished. Also included is a column for suggested level of CM control to be applied to the activity/product, from an Industry perspective. Future iterations will include a more complete dataset covering columns for entry criteria, exit criteria and related products from other skillcodes/disciplines. This Bulletin also has future considerations for a couple of specific examples regarding how to use the document (i.e., a day in the life), from start to finish, assuming different CM user skill levels are involved.
Article
2014-06-16
SAE International and the Consumer Electronics Association (CEA) have signed a two-year memorandum of understanding to build a cooperative partnership in the standardization of vehicle electronics and consumer electronics products to improve the driving experience.
Standard
2014-06-16
This SAE Aerospace Recommended Practice (ARP) sets forth criteria for the installation, inflation, inspection, and maintenance of aircraft tires as well as criteria for the maintenance of the operating environment so as to achieve the purpose stated in 1.1. (Definitions of terms related to aircraft tires are found in 2.2.)
WIP Standard
2014-06-11
This document establishes standard graphical symbols and color conventions for use in either still (static) or animated graphics used for communicating service information. This document’s purpose is to communicate conventions for using those symbols and colors to accurately and consistently communicate intended information via graphics-based documentation. These practices are intended for use in service procedures, assembly instructions, training materials, and similar applications when trying to minimize the amount of human natural language text used within the document. The still and animated graphical conventions referenced should support effective communication via paper and “traditional” electronic media. The conventions can also extend to documenting via additional electronic delivery paradigms such as Augmented Reality (AR). This document is intended for organizations interested in using graphics-based documentation to record and communicate assembly, adjustment, maintenance, and other service procedures.
Standard
2014-06-10
This SAE Aerospace Information Report (AIR) provides guidelines for the development of landing gear fatigue spectra for the purpose of designing and certification testing of Part 25 landing gear. Many of the recommendations herein are generalizations based on data obtained from a wide range of landing gears. The aircraft manufacturer or the landing gear supplier is encouraged to use data more specific to their particular undercarriage whenever possible.
WIP Standard
2014-06-10
This SAE Recommended Practices specifies a procedure for determining structural strength and fatigue life of disc-brake caliper assemblies which are satisfactory for vehicle usage. It is applicable to new caliper assemblies which are employed in passenger car and truck brake systems utilizing hydraulic brake fluids. Brake design and vehicle performance requirements are not included. Specification limits are left to the discretion of the responsible manufacturer. This procedure was developed for base brake operation and does not consider some unusual effects of ABS (Anti-Lock-Brake System) or Traction Control systems which may have a significant effect on the caliper. Careful analysis of the particular type ABS and/or Traction Control should be made and additional tests may be required which are not included in this document.
Standard
2014-06-10
On-Board Diagnostic (OBD) regulations require passenger cars, and light and medium duty trucks, to support communication of a minimum set of diagnostic information to off-board “generic” test equipment. This document specifies the diagnostic data which may be required to be supported by motor vehicles and external test equipment for diagnostic purposes which pertain to motor vehicle emission-related data. SAE J1979 was originally developed to meet U.S. OBD requirements for 1996 and later model year vehicles. ISO 15031 5 was based on SAE J1979 and was intended to combine the U.S. requirements with European OBD requirements for 2000 and later model year vehicles.
WIP Standard
2014-06-05
This SAE Aerospace Information Report (AIR) provides a description of a screening method for use in the field for verifying an AMS 1428 anti-icing fluid is above its minimum low shear viscosity as published with holdover time guidelines. The test will determine if the fluid is (a) satisfactory, (b) unsatisfactory, or (c) borderline needing more advanced viscometry testing. Other field tests may be required to determine if an anti-icing fluid is useable, such as refractive index, appearance or other tests as may be recommended by the fluid manufacturer.
WIP Standard
2014-06-03
This handbook is designed to assist program management and/or systems engineering management in managing the transition to lead-free (Pb-free) electronics to assure product reliability and performance.

Programs may inadvertently introduce Pb-free elements (including piece part finish, printed wiring board finish, or assembly solder) if careful coordination between buyer and supplier is not exercised. For example, piece part manufacturers may not always change part numbers to identify Pb-free finishes, especially if the previous tin-lead (Sn/Pb)-finished piece part has been discontinued. Detailed examination of piece parts and documents at receiving inspection while crucial, may not be sufficient to identify Pb-free piece parts.

Note: Pb-free technology can impact any program regardless of whether the program itself is exempt or bound by environmental regulations. The industry conversion to Pb-free solder technology may affect an aerospace program in one or both of the following ways: 1.

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