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Viewing 61 to 90 of 7659
2016-04-05
Technical Paper
2016-01-0279
Chong Chen, Zhenfei Zhan, Jie Li, Yazhou Jiang, Helen Yu
Abstract To reduce the computational time of the iterations in robust design, meta-models are frequently utilized to approximate time-consuming computer aided engineering models. However, the bias of meta-model uncertainty largely affects the robustness of the prediction results, this uncertainty need to be addressed before design optimization. In this paper, an efficient uncertainty quantification method considering both model and parameter uncertainties is proposed. Firstly, the uncertainty of parameters are characterized by statistical distributions. The Bayesian inference is then performed to improve the predictive capabilities of the surrogate models, meanwhile, the model uncertainty can also be quantified in the form of variance. Monte Carlo sampling is finally utilized to quantify the compound uncertainties of model and parameter. Furthermore, the proposed uncertainty quantification method is used for robust design.
2016-04-05
Technical Paper
2016-01-0289
Balakrishna Chinta
Abstract Mahalanobis Distance (MD) is gaining momentum in many fields where classification, statistical pattern recognition, and forecasting are primary focus. It is a multivariate method and considers correlation relationships among parameters for computing generalized distance measure to separate groups or populations. MD is a useful statistic in multivariate analysis to test that an observed random sample is from a multivariate normal distribution. This capability alone enables engineers to determine if an observed sample is an outlier (defect) that falls outside the constructed (good) multivariate normal distribution. In Mahalanobis-Taguchi System (MTS), MD is suitably scaled and used as a measure of severity in abnormality assessment. It is obvious that computed MD depends on values of parameters observed on a random sample. All parameters may not equally impact MD. MD could be highly sensitive with respect to some parameters and less sensitive to some other parameters.
2016-04-05
Technical Paper
2016-01-0320
Tejas Janardan Sarang, Mandar Tendolkar, Sivakumar Balakrishnan, Gurudatta Purandare
Abstract In the automotive industry, multiple prototypes are used for vehicle development purposes. These prototypes are typically put through rigorous testing, both under accelerated and real world conditions, to ensure that all the problems related to design, manufacturing, process etc. are identified and solved before it reaches the hands of the customer. One of the challenges faced in testing, is the low repeatability of the real world tests. This may be predominantly due to changes in the test conditions over a period of time like road, traffic, climate etc. Estimating the repeatability of a real world test has been difficult due to the complex and multiple parameters that are usually involved in a vehicle level test and the time correlation between different runs of a real world test does not exist. In such a scenario, the popular and the well-known univariate correlation methods do not yield the best results.
2016-04-05
Technical Paper
2016-01-0376
Yunkai Gao, Zhaoxuan Feng, Jianguang Fang, Shihui Wang
Abstract The performance of the rear axle plays an important role in the performance of vehicle, and its fatigue durability is an integral part in the vehicle development. Taking a SUV model as the research subject, a new methodology of multi-channel spindle coupled road simulator and fatigue simulation analysis for rear axle assembly was introduced in the paper, aiming to address the fatigue design and its verification for the rear axle in the development phase. Firstly, road loads in the proving ground was collected by arranging proper sensors. Secondly, physical iteration was performed on the multichannel spindle coupled road simulator by taking six component forces at the wheel hub as the target signals. Then, after the time waveform replication of the loads the durability test was conducted. Finally, the validated simulation model was successfully implemented to improve the fatigue life of the axle.
2016-04-05
Journal Article
2016-01-0075
Steven Holland, Tim Felke, Luis Hernandez, Robab Safa-Bakhsh, Matthew A. Wuensch
Abstract Health Ready Components are essential to unlocking the potential of Integrated Vehicle Health Management (IVHM) as it relates to real-time diagnosis and prognosis in order to achieve lower maintenance costs, greater asset availability, reliability and safety. IVHM results in reduced maintenance costs by providing more accurate fault isolation and repair guidance. IVHM results in greater asset availability, reliability and safety by recommending preventative maintenance and by identifying anomalous behavior indicative of degraded functionality prior to detection of the fault by other detection mechanisms. The cost, complexity and effectiveness of the IVHM system design, deployment and support depend, to a great extent, on the degree to which components and subsystems provide the run-time data needed by IVHM and the design time semantic data to allow IVHM to interpret those messages.
2016-04-05
Technical Paper
2016-01-0865
R. Lockett, Mahesh Jeshani, Kassandra Makri, Richard Price
Abstract High-speed planar laser Mie scattering and Laser Induced Fluorescence (PLIF) were employed for the determination of Sauter Mean Diameter (SMD) distribution in non-evaporating diesel sprays. The effect of rail pressure, distillation profile, and consequent fuel viscosity on the drop size distribution developing during primary and secondary atomization was investigated. Samples of conventional crude-oil derived middle-distillate diesel and light distillate kerosene were delivered into an optically accessible mini-sac injector, using a customized high-pressure common rail diesel fuel injection system. Two optical channels were employed to capture images of elastic Mie and inelastic LIF scattering simultaneously on a high-speed video camera at 10 kHz. Results are presented for sprays obtained at maximum needle lift during the injection. These reveal that the emergent sprays exhibit axial asymmetry and vorticity.
2016-04-05
WIP Standard
AS6453A

This SAE Aerospace Standard (AS), identical to ISO 14186, specifies the minimum design and performance criteria and testing methods of fire containment covers (FCCs) used either:

    a. in those cargo compartments of civil transport aircraft where they constitute one means of complying with applicable airworthiness regulations, or
    b. on a voluntary basis, when deemed appropriate by operators to improve fire protection in aircraft cargo compartments where airworthiness regulations do not mandate their use.

2016-04-05
Technical Paper
2016-01-0274
Sharon L. Honecker, David J. Groebel, Adamantios Mettas
Abstract In order to accurately predict product reliability, it is best to design a test in which many specimens are tested for a long duration. However, this scenario is not often practical due to economic and time constraints. This paper describes a reliability test in which a limited number of specimens are tested with little time remaining before the scheduled start of production. During the test, an unexpected failure mode that can be mitigated through a product redesign occurs. Because the scheduled start of production is near, there is not enough time to perform a test with redesigned specimens, so the current test proceeds as planned. We discuss several methods and the associated assumptions that must be made to account for the presence of the unexpected failure mode in the test data in order to make predictions of reliability of the redesigned product.
2016-04-05
Journal Article
2016-01-0269
Zhigang Wei, Michael Start, Jason Hamilton, Limin Luo
Durability and reliability performance is one of the most important concerns for vehicle components and systems, which experience cyclic fatigue loadings and may eventually fail over time. Durability and reliability assessment and associated product validation require effective and robust testing methods. Several testing methods are available and among them, three basic testing methods are widely used: life testing, binomial testing (bogey testing), and degradation testing. In fact, their commonalities, differences, and relationships have not been clearly defined and fully understood. Therefore, the maximum potential of these testing methods to generate efficient, optimized, and cost-effective testing plans, consistent results, and meaningful results interpretation have been significantly limited. In this paper, a unified framework for representing these testing methods and conducting reliability analysis in a single damage-cycle (D-N) diagram is provided.
2016-04-05
Technical Paper
2016-01-0377
Wallace Ferreira, Trenton Meehan, Valdir Cardoso, Neil Bishop
Abstract The objective of this paper is to demonstrate that frequency domain methods for calculating structural response and fatigue damage can be more widely applicable than previously thought. This will be demonstrated by comparing results of time domain vs. frequency domain approaches for a series of fatigue/durability problems with increasing complexity. These problems involve both static and dynamic behavior. Also, both single input and multiple correlated inputs are considered. And most important of all, a variety of non-stationary loading types have been used. All of the example problems investigated are typically found in the automotive industry, with measured loads from the field or from the proving ground.
2016-04-05
Technical Paper
2016-01-1112
Byeong Wook Jeon, Sang-Hwan Kim, Donghoon Jeong, Joseph Young-il Chang
Abstract In general, driving performance is developed to meet preference of average customers. But there is no single standardized guideline which can satisfy various driving tastes of all drivers whose gender, cultural background, and age are different. To resolve this issue, automotive companies have introduced drive mode buttons which drivers can manually select from Normal, Eco, and Sport driving modes. Although this multi-mode manual systems is more efficient than single-mode system, it is in a transient state where drivers need to go through troubles of frequently selecting their preferred drive mode in volatile driving situations It is also doubtful whether the three-categorized driving mode can meet complex needs of drivers.. In order to settle these matters, it is necessary to analyze individual driving style automatically and to provide customized driving performance service in real time.
2016-04-05
Technical Paper
2016-01-0329
Piyush Bubna, Michael P. Humbert, Marc Wiseman, Enrico Manes
Abstract Conventional car manufacturing is extremely capital and energy-intensive. Due to these limitations, major auto manufacturers produce very similar, if not virtually identical, vehicles at very large volumes. This limits potential customization for different users and acts as a barrier to entry for new companies or production techniques. Better understanding of the barriers for low volume production and possible solutions with innovative production techniques is crucial for making low volume vehicles viable and accelerating the adoption of new production techniques and lightweight materials into the competitive marketplace. Additive manufacturing can enable innovative design with minimal capital investment in tooling and hence should be ideal for low and perhaps high volume parts. For this reason, it was desired to evaluate potential opportunities in manufacturing automotive parts with additive techniques.
2016-04-05
Technical Paper
2016-01-0283
Joydip Saha, Harry Chen, Sadek Rahman
Abstract More stringent federal emission regulations and fuel economy requirements have driven the automotive industry toward more sophisticated vehicle thermal management systems in order to best utilize the waste heat and minimize overall power consumption. With all new technologies and requirements, how to properly design, optimize, and control the vehicle thermal and cooling systems become great challenges to automotive engineers. Model based approach has become essential to the new thermal management system architectures design and evaluation of the optimal system solutions. This paper will discuss how the model based vehicle thermal system simulation tools have been developed from analytical & empirical data, and have been used for assessment and development of new thermal management system architectures.
2016-04-05
Technical Paper
2016-01-0270
Zhigang Wei, Limin Luo, Michael Start, Litang Gao
Product validation and reliability demonstration require testing of limited samples and probabilistic analyses of the test data. The uncertainties introduced from the tests with limited sample sizes and the assumptions made about the underlying probabilistic distribution will significantly impact the results and the results interpretation. Therefore, understanding the nature of these uncertainties is critical to test method development, uncertainty reduction, data interpretation, and the effectiveness of the validation and reliability demonstration procedures. In this paper, these uncertainties are investigated with the focuses on the following two aspects: (1) fundamentals of the RxxCyy criterion used in both the life testing and the binomial testing methods, (2) issues and benefits of using the two-parameter Weibull probabilistic distribution function.
2016-04-05
Technical Paper
2016-01-0072
Jihas Khan
Abstract Unified Diagnostic Service and On Board Diagnostics require a client side device with necessary software to implement certain specific algorithms. This paper proposes a highly optimized and generic model based architecture to implement client side algorithms used in Unified Diagnostic Service systems and with On Board Diagnostics which can be reused for any hardware target. The proposed method can implement particular algorithms which include flow control, timing control, database parsing, logging of messages, diagnostic database parsing, security unlock, intuitive HMI layer, DTC display with textual information, frame control, multi network - multi ECU support, software flashing, physical-functional message handling, and interfacing for multiple hardware host devices. Re-usability of this model based product ensures that it can be ported to the diagnostic tool used by a work shop engineer or by a diagnostics validation engineer working at OEM or Tier 1suppliers.
2016-04-05
Technical Paper
2016-01-0073
Peter Subke, Muzafar Moshref
Abstract Passenger cars are equipped with an OBD connector according to SAE J1962 / ISO 15031-3. Passenger cars that support ISO UDS on DoIP use the same connector with Ethernet pins according to ISO/DIS 13400-4 (Ethernet diagnostic connector). If external test equipment is connected to the Ethernet diagnostic connector via a 100BASE-TX cable with the RJ45 connector at the tester, a VCI is not necessary anymore. With a device that fits the Ethernet diagnostic connector physically and acts as a converter between the Ethernet signals and WLAN, external test equipment that supports wireless communication, can be connected to the vehicle. Examples for such wireless external test equipment include Android/iOS- based smart phones and tablets with purpose-made applications (APPs). The software components of external test equipment are standardized in ISO 22900 (MVCI). The MVCI D-Server processes data in ODX (ISO 22901) and sequences in OTX (ISO 13209).
2016-04-05
Journal Article
2016-01-0076
Mostafa Anwar Taie, Eman Magdy Moawad, Mohammed Diab, Mohamed ElHelw
Abstract New challenges and complexities are continuously increasing in advanced driver assistance systems (ADAS) development (e.g. active safety, driver assistant and autonomous vehicle systems). Therefore, the health management of ADAS’ components needs special improvements. Since software contribution in ADAS’ development is increasing significantly, remote diagnosis and maintenance for ADAS become more important. Furthermore, it is highly recommended to predict the remaining useful life (RUL) for the prognosis of ADAS’ safety critical components; e.g. (Ultrasonic, Cameras, Radar, LIDAR). This paper presents a remote diagnosis, maintenance and prognosis (RDMP) framework for ADAS, which can be used during development phase and mainly after production. An overview of RDMP framework’s elements is explained to demonstrate how/when this framework is connected to database servers and remote analysis servers.
2016-04-05
Technical Paper
2016-01-0684
Shinji Matsuo, Eiji Ikeda, Yoshiaki Ito, Hiroyuki Nishiura
Abstract The engine in the new fourth generation Prius carries over the same basic structure as the 2ZR-FXE used in the third generation and incorporates various refinements to enhance fuel efficiency. Called the ESTEC 2ZR-FXE, the new engine incorporates various fuel efficient technologies to improve combustion characteristics, knocking, and heat management, while also reducing friction. As a result of this meticulous approach to enhancing fuel efficiency, the new engine is the first gasoline engine in the world to achieve a maximum thermal efficiency of 40%. This paper describes the fuel efficient technologies incorporated into this engine.
2016-04-05
Journal Article
2016-01-0639
Brian C. Kaul, Benjamin Lawler, Akram Zahdeh
Abstract Engine acoustics measured by microphones near the engine have been used in controlled laboratory settings for combustion feedback and even combustion phasing control, but the use of these techniques in a vehicle where many other noise sources exist is problematic. In this study, surface-mounted acoustic emissions sensors are embedded in the block of a 2.0L turbocharged GDI engine, and the signal is analyzed to identify useful feedback features. The use of acoustic emissions sensors, which have a very high frequency response and are commonly used for detecting material failures for health monitoring, including detecting gear pitting and ring scuffing on test stands, enables detection of acoustics both within the range of human hearing and in the ultrasonic spectrum. The high-speed acoustic time-domain data are synchronized with the crank-angle-domain combustion data to investigate the acoustic emissions response caused by various engine events.
2016-04-05
Standard
EIA649-2
This Standard applies to all products produced by NASA Headquarters and NASA Centers, including Component Facilities and Technical and Service Support Centers. This Standard may also apply to the Jet Propulsion Laboratory and suppliers/service providers to the extent specified in their agreements with NASA. This Standard may be cited in the CM requirements of NASA Headquarters, NASA Centers, Programs, Projects, and Supplier agreements.
2016-04-04
Standard
ARP1836C
This SAE Aerospace Recommended Practice (ARP) outlines the functional and design requirements for a b self-propelled belt conveyor for handling baggage and cargo at aircraft bulk cargo holds. Additional considerations and requirements may legally apply in other countries. As an example, for operation in Europe (E.U. and E.F.T.A.), the applicable EN standards shall be complied with.
2016-04-04
Standard
AIR6894
This document describes laser wire stripping technologies and recommendations to strip electrical single conductor and shielded cables intended for aerospace applications. These recommendations include: - Laser stripping safety guidelines - Laser stripping quality - Tool qualification - Tool inspection - User health and safety
2016-04-03
Standard
AIR4365B
This SAE Aerospace Information Report (AIR) describes procedures for use in the field to determine if 115/200 Volt, 400 Hz aircraft external electrical power connectors are excessively worn, which may result in the inability of the external power plug to be retained, intermittent electrical performance and arcing.
2016-03-31
WIP Standard
AMS1547B
This specification covers an electrolytic alkaline cleaner in the form of a water soluble powder.
2016-03-29
WIP Standard
J1337
This SAE Information Report covers the important fundamental maintenance and service precautions for all off-road single-piece and multi-piece rims. Detailed information on specific procedures concerning mounting, demounting, maintenance and service of a particular type, style, or design of off-road rim assembly can be obtained by consulting rim or tire manufacturers or distributors. These procedures and service precautions are guidelines to be considered in preparation of the machine service manual and operator's manual and workplace procedures. It is the intent of this Information Report to allow for further development and review of these guidelines and then make this document a Recommended Practice.
2016-03-22
WIP Standard
AMS2451D
This specification and its supplementary detail specifications establish the requirements for electrodeposition of metals by brush plating.
2016-03-17
WIP Standard
ARP6412
The scope of the Landing Gear Integrity Programs (LGIP) Aerospace Recommended Practice (ARP) is intended to assist in the safe-life structural integrity management of the landing gear system and subsystems components. In addition, component reliability, availability, and maintainability is included in a holistic LGIP.
2016-03-16
Standard
ARP6803
This SAE Aerospace Recommended Practice (ARP) examines a comprehensive construct of an Integrated Vehicle Health Management (IVHM) capability. This document provides a top-level view of the concepts, technology, and implementation practices associated with IVHM. This keystone document of the SAE HM-1 Committee is not intended as a legal document and does not provide detailed implementation steps, but does address general implementation concerns and potential benefits.
2016-03-15
WIP Standard
AIR6411
Provide information and guidance for landing gear operation in cold temperature environment. Covers all operational aspects on ground and in flight. Includes effects on: tires, wheels, brakes, shock strut, seals, and actuation.
2016-03-15
WIP Standard
AS5714
To assist the FAA with the technical update of TSO-C26d to address Electric Brake Actuation, standardize with TSO-C135a and address any remaining concerns with the current document.
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