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2015-06-15
Technical Paper
2015-01-2225
Peng Yu, Tong Zhang, Jing Li, Shiyang Chen, Rong Guo
Faced on transient vibration of EV, considering the characteristics of the electric drive system, active and passive integrated transient vibration control method of power train mounting system was proposed. First, models of power train system and mounting system were established, modal characteristics were grasped by simulation and experiment; a feed-forward controller was constructed from the active control perspective, mounting system transient vibration and power train torsion vibration were reduced; based on this, further optimization of mounting system was conducted from a passive control perspective. Results show that the active and passive integrated control method can effectively reduce the dynamic reaction force of mounting points, improve the vibration conditions of power train and body as well.
2015-06-15
Technical Paper
2015-01-2190
Manchi Venkateswara Rao, S Nataraja Moorthy, Prasath Raghavendran
Abstract Mount development and optimization plays an important role in the NVH refinement of vehicle as they significantly influence overall driving experience. Dynamic stiffness is a key parameter that directly affects the mount performance. Conventional dynamic stiffness evaluation techniques are cumbersome and time consuming. The dynamic stiffness of mount depends on the magnitude of load, frequency of application and the working displacement. The above parameters would be far different in the test conditions under which the mounts are normally tested when compared to operating conditions. Hence there is need to find the dynamic stiffness of mounts in actual vehicle operating conditions. In this paper, the dynamic stiffness of elastomeric mounts is estimated by using a modified matrix inversion technique popularly termed as operational path analysis with exogenous inputs (OPAX).
2015-06-15
Technical Paper
2015-01-2364
Xianpai Zeng, Jared Liette, Scott Noll, Rajendra Singh
The vibration isolation effectiveness of powertrain mount configurations is examined for electric vehicle application by focusing on the deteriorating effect introduced by internal mount resonances. Unlike internal combustion engines where mounts are typically designed only for static support and low frequency dynamics, electric motors have higher excitation frequencies in a range where mount resonances often occur. The problem is first analytically formulated by considering a simple 2-dimensional powertrain system. It is shown that by modifying the mount shape, the mount resonance(s) can be shifted while maintaining the same static rate. Further, vibration isolation is improved over a narrow frequency range by using non-identical mounts that split mount resonance peaks. Then a computational model for a realistic drive unit (containing electric motor, power invertor, and differential case) is considered.
2015-06-15
Journal Article
2015-01-2178
Mohamed El Morsy, Gabriela Achtenova
Abstract When localized fault occurs in a bearing, the periodic impulsive feature of the vibration signal appears in time domain and the corresponding Bearing Characteristic Frequencies (BCFs) emerge in frequency domain. The common technique of Fast Fourier Transforms (FFT) and Envelope Detection (ED) are always used to identify faults occurring at the BCFs. In the early stage of bearing failures, the BCFs contain very little energy and are often overwhelmed by noise and higher-level macro-structural vibrations. In order to extract the weak fault information submerged in strong background noise of the gearbox vibration signal, an effective signal processing method would be necessary to remove such corrupting noise and interference. Optimal Morlet Wavelet Filter and Envelope Detection (ED) are applied in this paper.
2015-06-15
Technical Paper
2015-01-2212
A. Elsawaf, H. Metered, T. Vampola, Z. Sika
Abstract Active vibration control is the most effective method used for suppressing vibrations from external sources. This paper presents the particle swarm optimization (PSO) algorithm to search about the optimum feedback controller gains for the active mount suspension, for the first time, to reduce the vibrations level of a structural system. It consists of vibrating mass and flexible beam subjected to an external disturbance. A mathematical model and the equations of motion of the structure system with an active mount suspension are simulated using Matlab/Simulink software. The active controller was designed to control the first three modes of the structure. The proposed PSO algorithm aims to minimize the acceleration of the suspended mass as the objective function with constraint of the actuator force. Vibrations level is examined theoretically in order to assess the effectiveness of the proposed controller.
2015-05-29
WIP Standard
AS4623E
This document defines the requirements for heavy-duty polytetrafluoroethylene (PTFE) lined, para-aramid reinforced, hose assembly suitable for use in 275 °F, 3000 psi aircraft systems where rapid rate pulsing and torsional/longitudinal flexing may occur in addition to normal hydraulic system loading. Size -16 and -20 are limited to +225 °F service.
2015-05-29
Standard
AS50881F
This specification covers all aspects in electrical wire interconnection systems (EWIS) from the selection through installation of wiring and wiring devices and optical cabling and termination devices used in aerospace vehicles. Aerospace vehicles include manned and unmanned airplanes, helicopters, lighter-than-air vehicles, missiles and external pods.
2015-05-28
Standard
AMS4259B
This specification covers an aluminum alloy in the form of sheet. This sheet has been used typically for structural parts requiring the strength of 2024-T3 and lower density, but usage is not limited to such applications.
2015-05-28
Standard
AMS4943K
This specification covers a titanium alloy in the form of seamless tubing.
2015-05-27
Article
Efforts to replace tropical rubber trees with a wild desert shrub that grows in Southwestern U.S. and Mexico are just beginning to bear fruit.
2015-05-26
WIP Standard
AS6449B
Revise composition requirement for the dry film lubricant by eliminating particle size requirement for molybdenum disulphide in section 3.2.4.
2015-05-26
Standard
AS6117A
SCOPE IS UNAVAILABLE.
2015-05-26
Standard
AMS2770M
This specification specifies the engineering requirements for heat treatment, by part fabricators (users) or their vendors or subcontractors, of parts (See 8.8.1). It also covers heat treatment by warehouses or distributors converting raw material from one temper to another temper (See 1.3 and 8.5). It covers the following aluminum alloys: 1100, 2004, 2014, 2017, 2024, 2098, 2117, 2124, 2219, 2224, 3003, 5052, 6013, 6061, 6063, 6066, 6951, 7049, 7050, 7075, 7149, 7178, 7249, 7475
2015-05-20
WIP Standard
AIR6510
This SAE Aerospace Information Report (AIR) comprises the technical terms and nomenclature, together with their definitions and abbreviations that are used in Aircraft Fuel Systems.
2015-05-20
WIP Standard
AS4130C
Scope is unavailable.
2015-05-20
WIP Standard
AS4136C
Scope is unavailable.
2015-05-20
WIP Standard
AS4134C
Scope is unavailable.
2015-05-19
Standard
AS9132B
This standard defines uniform quality and technical requirements relative to metallic parts marking performed using "data matrix symbology" within the aviation, space, and defense industry. ISO/IEC 16022 specifies general requirements (e.g., data character encodation, error correction rules, decoding algorithm). In addition to ISO/IEC 16022 specification, part identification with such symbology is subject to the requirements in this standard to ensure electronic reading of the symbol. The marking processes covered by this standard are as follows: - Dot Peening - Laser - Electro-Chemical Etching Further marking processes will be included, if required. Unless specified otherwise in the contractual business relationship, the company responsible for the design of the part shall determine the location of the data matrix marking. Symbol position should allow optimum illumination from all sides for readability. This standard does not specify information to be encoded.
2015-05-13
WIP Standard
AS45909A
The specification covers the requirements for locked-in studs. The method of locking in the stud is by means of a serrated collar and an accessory lockring with matching serrations installed within the parent material to prevent rotation.
2015-05-13
Standard
AMS3733C
This specification covers a highly filled epoxy potting compound supplied as a two-component system.
2015-05-13
Standard
AMS3647D
This specification covers polyfluoroethylenepropylene in the form of film and sheet 0.020 inch (0.51 mm) and under in nominal thickness. These products have been used typically for electrical, electronic, and mechanical applications requiring a chemically-inert film of the fluorocarbon family, having high dielectric strength and volume resistivity, and being free from pinholes and electrical flaws. Usage is not limited to such applications.
2015-05-13
Standard
AMS3652D
This specification covers one grade of polytetrafluoroethylene (PTFE) resin in the form of film, normally produced by skiving. This film has been used typically for gaskets and other parts for use up to 260 degrees C (500 degrees F) where chemical resistance or anti-stick characteristics are required but where high mechanical or electrical characteristics are not important, but usage is not limited to such applications.
2015-05-13
WIP Standard
ARP6339
This ARP provides recommended practice on the considerations and methodology to demonstrate acceptable performance of the Engine components / fuel system, and APU, whilst operating throughout the flight cycle / engine duty for continuous operation with iced fuel and short duration operation with a snowshower resulting from release of accreted ice from fuel washed surfaces, where no anti-icing additives are present (e.g. Fuel System Icing Inhibitor FSII or alternative). Two scenarios must be considered when demonstrating the capability of Engine components / fuel system, and APU to operate with fuel borne ice to satisfy certification regulations applications in support of FAA Part 23 and Part 25, CFR Part 33, and corresponding EASA CS-E regulations, and equivalent Military application requirements.
2015-05-12
WIP Standard
ARP5448/4A
This test method outlines a recommended procedure for performing bond integrity tests of bonded peelable woven fabric reinforced polytetrafluoroethylene (PTFE) liners, hereafter referred to within this document as "PTFE liner" or "liner". The data from these tests shall be used to determine if the product meets the "bond integrity" requirements of the applicable specifications.

Bearings covered by this test method shall be plain shperical, track roller, journal or rod end bearing with PTFE liners.

2015-05-12
Standard
J1939DA_201505
This document is intended to supplement the J1939 documents by offering the J1939 information in a form that can be sorted and search for easier use. The J1939 Digital Annex, introduced in August 2013, offers key J1939 technical data in an Electronic Spreadsheet that can be easily searched, sorted, and adapted to other formats. J1939DA contains all of the SPNs (parameters), PGNs (messages), and other J1939 data previously published in the SAE J1939 top level document. J1939DA also contains all of the SLOTs, Manufacturer ID Codes, NAME Functions, and Preferred Addresses previously published in the SAE J1939 top level and the J1939-71 document. J1939DA contains the complete technical details for all of the SPNs and PGNs previously published in the SAE J1939-71 document. It also includes the supporting descriptions and figures previously published in the SAE J1939-71 document.
2015-05-11
WIP Standard
J2286
The interface document SAE J2286 revises the requirements for file formats as described in SAE J1924. This document describes Interface 1 (I/F 1) in SAE J2214, SAE J1708. This document does not imply the use of a specific hardware interface, but may be used with other hardware interfaces such as SAE J1939. The requirements of SAE J2286 supersede the requirements defined by SAE J1924.
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