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Viewing 1 to 30 of 15378
2015-06-15
Technical Paper
2015-01-2212
A. Elsawaf, H. Metered, T. Vampola, Z. Sika
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 transmitted vibrations to the suspended mass placed over a structure. A mathematical model and the equations of motion of the structure system with an active mount suspension are derived and simulated using Matlab/Simulink software. The proposed PSO algorithm aims to minimize the acceleration of the suspended mass as the objective function with constraint of the actuator force. System performance criteria are evaluated in both the time and frequency domains in order to count the effectiveness of the proposed controller. The simulation results reveal that the proposed feedback controller gains tuned by PSO algorithm offer a significant improvement of the vibration isolation compared with both the passive and active mount controlled using the linear quadratic regulator (LQR).
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
2015-01-2178
Mohamed El Morsy, Gabriela Achtenova
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. However, one limitation of frequency-domain analysis is its inability to handle non-stationary waveform signals, which are very common when machinery faults occur. 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
2015-01-2190
Manchi Venkateswara Rao, S Nataraja Moorthy, Prasath Raghavendran
Mount development and optimization plays a significant role in vehicle NVH refinement 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 load, frequency of application and the 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.
2015-04-30
Standard
J1453/2_201504
1.1 Purpose The three parts of SAE J1453 cover material, dimensional, and performance requirements of steel O-ring face seal (ORFS) connectors for tubing and the O-ring face seal interface and nut portion of hose stem assemblies for nominal tube diameters of 6 mm through 38 mm and for nominal hose diameters 6.3 mm through 38 mm. SAE J1453-2 covers the requirements for “metric based” O-ring face seal connectors to metric stud ends along with the associated adapters, bulkhead and union connectors. Metric hex wrenching flats are used throughout this standard. 1.2 Field of Application These connectors are intended for general application and hydraulic systems on industrial equipment and commercial products, where elastomeric seals are acceptable to overcome leakage and variations in assembly procedures. These connectors are capable of providing leak proof full flow connections in hydraulic systems operating from 95 kPa vacuum to the working pressures shown in Table 3.
2015-04-28
WIP Standard
AS6893
This standard establishes the requirements for antifriction ball bearings primarily intended for use in aircraft electrical generators and motor-generators.
2015-04-28
WIP Standard
ARP5448/1A
This test method outlines the recommended procedure for performing radial limit load and ultimate load tests on low speed airframe and high speed helicopter rotor head bearings. Bearings covered by this test method shall be plain sleeve or spherical type in either annual or rod end configuration.
2015-04-28
Standard
AS1078A
SCOPE IS UNAVAILABLE.
2015-04-28
Standard
AS567K
This SAE Aerospace Standard (AS) covers devices whose primary function is the retention of fasteners, except for such devices that are integral with the item being retained.
2015-04-28
Standard
J126_201504
This SAE Recommended Practice outlines a procedure for selecting the proper specification for carbon steel sheet and strip which are purchased to make an identified part. Specifications considered are: ASTM A109-Steel, Carbon, Cold Rolled Strip. ASTM A569-Steel, Carbon (0.15 maximum percent), Hot Rolled Sheet, Commercial Quality (HRCQ). ASTM A621-Steel, Sheet, Carbon, Hot Rolled, Drawing Quality (HRDQ). ASTM A622-Steel, Sheet, Carbon, Hot Rolled, Drawing Quality, Special Killed (HRDQSK). ASTMA568-Steel, Carbon and High-Strength Low-Alloy Hot Rolled Sheet, and Cold Rolled Sheet, General Requirements. ASTM A366-Steel, Carbon, Cold Rolled Sheet, Commercial Quality (CRCQ). ASTM A619-Steel, Sheet, Carbon, Cold Rolled, Drawing Quality (CRDQ). ASTM A620-Steel, Sheet, Carbon, Cold Rolled, Drawing Quality, Special Killed (CRDQSK). ASTM A749M-Steel, Carbon and High-Strength Low-Alloy, Hot Rolled Strip, General Requirements.
2015-04-28
Standard
J1562_201504
Zinc and zinc-alloy coated steel is used to enhance a structure’s protection against corrosion degradation. For the purpose of this SAE Recommended Practice, a galvanized coating is defined as a zinc or zinc-alloy metallic coating. The selection of the optimum galvanized steel sheet product depends on many factors, the most important being: desired corrosion protection, formability, weldability, surface characteristics, and paintability. The trade-offs of these product characteristics are more complex than is the case with uncoated steel sheet products.
2015-04-28
Standard
J2329_201504
This SAE Recommended Practice establishes mechanical property ranges for low-carbon automotive hot-rolled sheet, cold-rolled sheet, and metallic-coated sheet steels. It also contains information that explains the different nomenclature used with these steels.
2015-04-28
Standard
J2745_201504
This SAE Recommended Practice defines various grades of continuously cast high-strength sheet steels and establishes mechanical property ranges. These sheet steels can be formed, welded, assembled and painted in automotive manufacturing processes. They can be specified as hot-rolled or cold-rolled sheet. Furthermore, they can be coated (hot-dipped galvanized, hot-dipped galvannealed, and electrogalvanized) or uncoated. Not all combinations of strength, dimensions and coatings may be commercially available; consult your steel supplier for details.
2015-04-28
Standard
J2392_201504
This SAE recommended practice defines and establishes tolerances and attributes of cold rolled strip steels. Differences between cold rolled strip and cold rolled sheet products are discussed so that process designers can make informed material selection decisions.
2015-04-28
Standard
J863_201504
This SAE Recommended Practice describes methods for determining plastic deformation encountered in the forming or drawing of sheet steel.
2015-04-22
WIP Standard
AS22227C
This standard establishes the requirements for antifriction ball bearings primarily intended for use in aircraft electrical generators and motor-generators.
2015-04-22
WIP Standard
J285
This SAE recommended practice provided standard dimensions for liquid fuel dispenser nozzle spouts and a system for differentiating between nozzels that dispense liquid fuel into vehicles with Spark Ignition (SI) Engines and compression Ignition (CI) Engines for land vehicles. Current legal definitions only distinguish between "UNLEADED Fuel" and "All Other Types of Fuel." These definitions are no longer valid. This document establishes a new set of definitions that have practical application to current automobile liquid fuel inlets and liquid fuel dispenser nozzle spouts.
2015-04-21
Standard
AS49011A
SCOPE IS UNAVAILABLE.
Viewing 1 to 30 of 15378

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