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Viewing 61 to 90 of 11057
2017-09-17
Journal Article
2017-01-2511
Toshikazu Okamura
Abstract The most fundamental function of an automobile brake system is assuring stable braking effectiveness under various conditions. In a previous paper (2004-01-2765), the author et al. confirmed that the friction behavior of disc brakes during running-in depends on both the friction materials and discs’ friction-surface textures. Various friction pairs were tested by combining discs finished with roller-burnishing and grinding and five friction materials including NAO and low-steel. Some NAO material exhibited large effects on the difference in friction behaviors between the discs’ surface textures. A disc finished with roller-burnishing needed a longer running-in period than that with grinding. In another paper (2011-01-2382), a further experiment was conducted by combining eight surface textures (finished under four turning conditions with and without additional roller-burnishing), two NAO materials, and two rotational directions.
2017-09-17
Journal Article
2017-01-2496
Enrico Galvagno, Antonio Tota, Alessandro Vigliani, Mauro Velardocchia
Brake systems represent important components for passenger cars since they are strictly related to vehicle safety: Anti-lock Braking Systems (ABS) and Electronic Stability Control (ESC) are the most well-known examples. The paper is focused on the characterization of the braking hydraulic plant and on the design of a pressure following control strategy. This strategy is aimed at pursuing performances and/or comfort objectives beyond the typical safety task. Caliper pressure dynamics is evaluated through a lumped parameter model which is used to design the controller. The low-level logic (focus of the paper) consists of a Feedforward and Proportional Integral controller. A Hardware In the Loop (HIL) braking test bench is adopted for pressure controller validation by providing some realistic reference pressure histories evaluated by a high-level controller.
2017-09-17
Journal Article
2017-01-2527
Dejie Huang, Xu Zhou, Peiqing Qian, Chao Wen, Yu Liu
Abstract The seal structure and key parameters of wheel bearing were introduced. Research on sealing failure diagnosis, abrasive scratch analysis, residual interference, and abrasion reconstruction was carried out for a typical seal structure. Based on these methods of scientific failure analysis, eight causes of seal failure were summarized systematically, which were important for the guidance of seal design and failure analysis of wheel bearings.
2017-09-17
Journal Article
2017-01-2522
Chao Wen, Lu Zhang, Tong Luo, Dejie Huang, Yu Liu
Abstract The actual installed conditions of 1st, 2nd and 3rd generation of wheel bearing were introduced. The theoretical factors of the axial fastening force for the axle (or CVJ bolts) and nuts were analyzed and the requirements for building up a precise axial force test system were given out. Four testing plans were discussed for the requirements. Based on the cases, the axial force test system was built up, and the axial force test was successfully carried out for the front wheel bearing of a car.
2017-09-17
Journal Article
2017-01-2524
Sebastiano Rizzo, Stefano Pagliassotto
Abstract Wheel bearings are safety-critical automotive components. For this application, the steel rolling elements are subjected to fatigue failure and therefore play a key role in overall bearing fatigue life performance. This performance is influenced by metallurgical, mechanical, and physical properties obtained by precise manufacturing process parameters. These properties are continuously analyzed and are evolving at all bearing manufacturing companies. Last year, the Precision Bearing Components (PBC) Group of NN Inc., a global supplier of steel rolling elements for wheel bearings, developed a non-conventional heat treatment process for 100Cr6 (SAE 52100) rolling element steel for improved fatigue performance. The results of wheel bearing rolling contact fatigue (RCF) tests showed the importance of rolling element dimensional stability. As retained austenite transformed to the martensite phase, rolling element volume increase occurred, leading to fatigue failure.
2017-09-17
Journal Article
2017-01-2525
Seungpyo Lee, Mincheol Park
Abstract The primary functions of bearing seals are to prevent lubrication from escaping and foreign material from entering, the effectiveness of which is determined by the design of the seal lips. Bearings with low friction rotation are in great demand in the automotive market as a direct result of enforced vehicle fuel economy and reduced CO2 emissions regulations. Therefore, bearings with good sealing function and low friction rotation are required. This makes designing a seal challenging as the ideologies of high seal-ability and low friction rotation tend to be contradictory. Current estimations of bearing seal friction or rotational torque require significant time and cost through empirical methods of trial and error. Research into the estimation of bearing rotational torque through numerical analysis, based on finite element methods, is the focal point of this paper.
2017-09-17
Journal Article
2017-01-2526
Robert G. Sutherlin
Abstract As material cleanliness and bearing lubrication have improved, wheel bearings are experiencing less raceway spalling failures from rotating fatigue. Warranty part reviews have shown that two of the larger failure modes for wheel bearings are contaminant ingress and Brinell damage from curb and pothole impacts. Warranty has also shown that larger wheels have higher rates of Brinell warranty. This paper discusses the Brinell failure mode for bearings. It reviews a vehicle test used to evaluate Brinell performance for wheel bearings. The paper also discusses a design of experiments to study the effects of factors such as wheel size, vehicle loading and vehicle position versus the bearing load from a vehicle side impact to the wheel. As the trend in vehicle styling is moving to larger wheels and low profile tires, understanding the impact load can help properly size wheel bearings.
CURRENT
2017-08-15
Standard
AS5714A
This SAE Aerospace Standard (AS) prescribes the Minimum Performance Standards (MPS) for wheel, brake, and wheel and brake assemblies to be used on aircraft certificated under 14 CFR Parts 23, 27, and 29. Compliance with this specification is not considered approval for installation on any aircraft.
2017-08-15
WIP Standard
J1939DA
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.
CURRENT
2017-08-14
Standard
AMS7301J
This specification covers low-alloy steel springs made of annealed round wire heat treated after forming.
CURRENT
2017-08-14
Standard
J1204_201708
This SAE Recommended Practice provides uniform procedures and minimum performance requirements for fatigue testing ferrous and aluminum wheels intended for normal highway service on travel, camping, and boat and light utility trailers drawn by passenger cars, light trucks, and multipurpose vehicles. For procedures and minimum performance requirements for wheels used on trucks, see SAE J267, and for wheels used on passenger cars, see SAE J328. For the application of passenger car and light truck wheels (inset less than 0.10 m) to this trailer service, use this procedure. For the application of heavier truck wheels (inset 0.10 m (or more)) use SAE J267. Mobile home service is outside the scope of this document. There are two basic test procedures described, a cornering fatigue test and radial fatigue test. The cornering test is directed at the wheel disc; whereas the radial test also examines the rim and attachment portion of the wheel.
2017-08-11
Journal Article
2017-01-9379
John Thomas, Shean Huff, Brian West, Paul Chambon
Abstract Aggressive driving is an important topic for many reasons, one of which is higher energy used per unit distance traveled, potentially accompanied by an elevated production of greenhouse gases and other pollutants. Examining a large data set of self-reported fuel economy (FE) values revealed that the dispersion of FE values is quite large and is larger for hybrid electric vehicles (HEVs) than for conventional gasoline vehicles. This occurred despite the fact that the city and highway FE ratings for HEVs are generally much closer in value than for conventional gasoline vehicles. A study was undertaken to better understand this and better quantify the effects of aggressive driving, including reviewing past aggressive driving studies, developing and exercising a new vehicle energy model, and conducting a related experimental investigation.
2017-08-10
Article
New compact utility leverages Fuji Heavy Industries' latest global platform for improved ride, handling, NVH attenuation and crashworthiness. But power and torque are lacking.
2017-08-10
WIP Standard
AS6541
Defines the requirements for a typical aircraft wheel valve assembly. Required material, tolerance(s) and appropriate finishes are provided.
CURRENT
2017-08-07
Standard
AMSQQW428B
This specification covers uncoated, round, high carbon steel wire for the fabrication of mechanical springs and wire forms for general purpose use.
2017-08-03
WIP Standard
J3153
To develop a recommended practice for taking photographs of a damaged vehicle to preserve evidence.
2017-08-03
Magazine
Hacked! Is automotive ready for the inevitable? Cybersecurity experts talk defense strategies. Active Aero takes flight Reconfigurable "smart" aerodynamic aids are stretching performance-car envelopes in every direction. The motorcycle's balanced future With its Ride Assist technology, Honda R&D moves two-wheelers toward autonomous capability. Honoring lightweight innovation Chrysler, Toyota, Faurecia and AP&T recognized with the 2017 Altair Enlighten Award for their efforts to reduce vehicle weight.
2017-08-02
Article
The American Chemistry Council and researchers at Michigan State University have demonstrated that a new “reversible” adhesive for multi-material joining actually gets stronger after use and repair/rebonding.
2017-07-31
Article
Boeing and Tata Advanced Systems Limited announced delivery of the first crown and tailcone assembly for the Indian configuration of the CH-47F Chinook helicopter.
2017-07-27
WIP Standard
J1406
This SAE Recommended Practice covers the application of hydraulic brake hose (as defined by current issue of SAE J1401) as used to provide a flexible hydraulic connection between wheel end or axle brake system components on motor vehicles. The purpose of this document is to outline design, operating, and service factors in routing a hydraulic brake hose assembly to a vehicle. It is intended to serve as a recommended practice for original equipment manufacturers. Vehicle design circumstances may exist that prevent strict adherence to this document. Any deviations should have the concurrence of all engineering functions involved.
CURRENT
2017-07-26
Standard
J2452_201707
This SAE Recommended Practice is applicable to pneumatic Passenger Car "P" Type, Light Truck Metric, and Light Truck High Flotation tires, or similar tires approved by bodies other than Tire & Rim Association. The methodology is applicable within normal operating ranges of vertical load and inflation pressure, and for velocities between 115 km/h and 15 km/h (71 mph and 9 mph) during a relatively short duration event such as a coastdown. This procedure is applicable only to operation in the free-rolling mode at zero slip and camber angle for ambient temperatures between 20 °C and 28 °C (68 °F and 82 °F) and for surfaces with diameters of 1.2 m (48 in) diameter or greater. Details regarding the equipment, tires, and test methods used specifically for validation of this document are included in Appendix A.
2017-07-24
Article
The new DRiV damping system makes pickups and SUVs drive and ride as well as they haul and tow
CURRENT
2017-07-24
Standard
J2625_201707
This procedure is applicable to squeal type noise occurrences for passenger car and light truck type vehicles that are used under conventional operating conditions. For the purposes of this test procedure, squeal is defined as occurring between 900 and 18 000 Hz.
CURRENT
2017-07-19
Standard
J1939DA_201707
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.
2017-07-18
WIP Standard
J2986
This Recommended Practice provides a common method to measure wear of friction materials (brake pad assemblies and brake shoes) and their mating part (brake rotor or brake drum). These wear measurements apply to brakes fitted on passenger cars and light trucks up to 4,540 kg of Gross Vehicle Weight Rating or vehicles category M1 on the European Community.
2017-07-18
WIP Standard
J3152
Define general taxonomy (classification) of the most common fixture designs. Provide general design, fabrication, and installation guidelines to improve repeatability, reproducibility of vehicle conditions (including preloading) of brake fixtures for inertia dynamometer NVH testing.
2017-07-18
WIP Standard
J3002
This procedure will outline the necessary test equipment (fixturing, dynamometer, data acquisition system, etc.) and test sequence required to test for low-frequency brake noise on a brake noise dynamometer. It is intended to complement SAEJ2521, which focuses on high-frequency brake squeal.
2017-07-14
Article
Designed in Japan with exterior surfacing finalized at Honda’s California studio, the 2018 Accord is up to 176 lb (89 kg) lighter than the outgoing model, depending on trim level. Key technical features include two new turbocharged gasoline engines, the first use of a 10-speed automatic transaxle (Honda’s own 10AT) in front-drive sedan, and the return to the low-cowl/thin pillar body architecture.
2017-07-14
Article
Audi's new active suspension uses a Mobileye monocular camera to generate vertical information from the road with a resolution of 1.2 to 6 inches. Combined with new all-wheel steering and an e-booster, the car greatly benefits from 48-V electrical power.
2017-07-14
WIP Standard
J2710
This SAE Recommended Practice describes test methods for measuring and identifying the lower order natural frequencies of an inflated radial tire with a fixed rim while expending modest effort and employing a minimum of test equipment. The methods apply to any size of radial tire so long as the test equipment is properly scaled to conduct the measurements for the intended test tire. Two types of boundary conditions are considered for the tire: unloaded and loaded against a flat surface. The test involves the performance and measurement of an input vibratory force (excitation) to the tire and the corresponding vibratory output (response). The data are suitable for use in determining parameters for road load models and for comparative evaluations of the measured properties in research and development. NOTES: The focus of this standard is identification and reporting of the lower order natural frequencies of the tire using a simple test procedure.
Viewing 61 to 90 of 11057

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