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This specification describes a method and acceptance criteria for testing automotive wire harness retainer clips. Retainer clips are plastic parts that hold a wire harness or electrical connector in a specific position. Typical plastic retainers work by having a set of “branches” that can be inserted into a hole sized to be easy to install but provide acceptable retention. This specification tests retainer clips for mechanical retention when exposed to the mechanical and environmental stresses typically found in automotive applications over a 15-year service life. This specification has several test options to allow the test to match to the expected service conditions. The variability of applications typically arises from different ambient temperatures near the clip, different proximity to automotive fluids, different exposure to standing water or water spray, and different thicknesses of the holes that the clip is inserted into.

This Surface Vehicle & Aerospace Recommended Practice offers best practices and a methodology by which IVHM functionality relating to components and subsystems should be integrated into vehicle or platform level applications. The intent of the document is to provide practitioners with a structured methodology for specifying, characterizing and exposing the inherent IVHM functionality of a component or subsystem using a common functional reference model, i.e., through the exchange of design-time data and the application of standard vehicle data communications interfaces. This document includes best practices and guidance related to the specification of the information that must be exchanged between the functional layers in the IVHM system or between lower-level components/subsystems and the higher-level control system to enable health monitoring and tracking of system degradation severity.

By detecting and diagnosing problems earlier in manufacturing, Voltaiq and PDF Solutions can reduce the number of recalls and improve the yield of quality battery cells and packs.

This work covers the historical development of Built-In-Test (BIT) for fiber optic interconnect links for aerospace applications using Optical Time Domain Reflectometry (OTDR) equipped transceivers. The original failure modes found that installed fiber optic links must be disconnected before diagnosis could begin, often resulting in “no fault found” (NFF) designation. In fact, the observed root cause was that most (85%) of the fiber optic link defects were produced by contamination of the connector end faces. In March of 2006, a fiber optics workshop was held with roughly sixty experts from system and component manufacturers to discuss the difficulties of fiber optic test in aerospace platforms. During this meeting it was hypothesized that Optical Time Domain Reflectometry (OTDR) was feasible using an optical transceiver transmit pulse as a stimulus. The time delay and amplitude of received reflections would correlate with the position and severity of link defects, respectively.

With the improvement of connectivity technologies, and the increase of data exchange capacity and cloud technologies, the usage of connected vehicle data by automakers is growing fast, and it represents an exciting, multi-faceted and high-growth area in the data analytics development – enabling a myriad of new possibilities, by including but not limited to: predicting failures in parts, accelerating issue detection and resolution, improve design validation, calibration updates over the air, advanced navigation assistance, passenger entertainment. The aim of this work is to present the process, methodologies and tools adopted in the implementation of an unsupervised machine learning solution based on data collected from connected vehicles whose main objective will be support the analysis of usage severity of the engine and transmission mounts parts of the vehicle.

The purpose of this document is to define design, construction, operational, and maintenance requirements for hydrogen fuel storage and handling systems in on-road vehicles. Performance-based requirements for verification of design prototype and production hydrogen storage and handling systems are also defined in this document. Complementary test protocols (for use in type approval or self-certification) to qualify designs (and/or production) as meeting the specified performance requirements are described. Crashworthiness of hydrogen storage and handling systems is beyond the scope of this document. SAE J2578 includes requirements relating to crashworthiness and vehicle integration for fuel cell vehicles. It defines recommended practices related to the integration of hydrogen storage and handling systems, fuel cell system, and electrical systems into the overall Fuel Cell Vehicle.

This SAE Recommended Practice identifies and defines requirements relating to the safe integration of the fuel cell system, the hydrogen fuel storage and handling systems (as defined and specified in SAE J2579) and high voltage electrical systems into the overall Fuel Cell Vehicle. The document may also be applied to hydrogen vehicles with internal combustion engines. This document relates to the overall design, construction, operation and maintenance of fuel cell vehicles.

Composites having synthetic and/or natural fiber reinforcement remain an active area of research for potential structural applications in automotive dashboards, underfloor members, etc. The hybridization of natural and synthetic fibers reinforced composites was shown to produce desirable mechanical properties close to existing materials. This study explores the Abaca/E-glass-reinforced epoxy composite, fabricated using the hand lay-up method, a four-layer composite with [0°/90°/90°/0°] fiber orientation was fabricated. E-glass was used to enhance the mechanical properties of Abaca/epoxy composites. Mechanical tests, namely tensile, compressive, flexural, impact, and hardness tests, and microstructural evaluation were performed on the hybrid composite using standard experimental techniques.

This paper introduces one functional safety development solutions of Dual Clutch Transmission (DCT) equipped with Position 2 (P2) hybrid control system, which mainly includes the concept development stage (only for selected part), the system development stage (only for selected part), the hardware development stage (only for selected part) and the software development stage (only for selected part). It is carried out based on ISO 26262 standard and the selected system topology (details can be found in the paragraph). In the concept development stage of the DCT equipped with P2 hybrid control system, the hazard analysis and risk assessment of the item will be carried out based on the selected objects according to defined working condition. Especially the hybrid transmission control features are analyzed. And the safety goals will be summarized according to the evaluation results.

In order to obtain a good understanding of mechanical behaviors of lithium-ion battery modules in electric vehicles, comprehensive experimental and numerical investigations were performed in the study. Mechanical indentation tests with different indentation heads, different loading directions and different impact speeds were performed on battery modules with prismatic cells. To mitigate thermal runaway, only fully discharged battery modules were used. The force-displacement responses and open circuit voltage were recorded and compared. It was found that the battery modules experienced different failure modes when subjected to mechanical abuse. Besides internal short circuit of cells, external short circuit from bus bar and vapor leakage of electrolyte were also found to deteriorate the mechanical and electrical integrity of the tested modules. Mechanical anisotropy and dynamic effect were found on the battery module.

As the power of electric vehicles (EVs), lithium-ion batteries (LIBs) are subjected to a variety of mechanical loads during electrochemical operation. Under this operating environment, lithium-ion batteries are at risk of internal short circuit, thermal runaway and even fire, threatening the safety of electric vehicles. The purpose of this paper is to investigate the mechanical behaviors and failure mechanisms of the battery separator to improve the safety of lithium-ion batteries under mechanical loads. In this study, uniaxial tensile, through-thickness compression and biaxial punch tests were performed to characterize two types of separators, dry-processed polypropylene (PP) separators and wet-processed ceramic-coated separators, and to analyze and compare their mechanical properties and failure modes. The comprehensive mechanical tests show that the failure modes of the different separator types are different, with the more anisotropic separator having more complex failure modes.

This SAE Recommended Practice applies to motor vehicle forward illumination systems and subsystems generated by discharge sources. It provides test methods, requirements, and guidelines applicable to the special characteristics of gaseous discharge lighting devices which supplement those required for forward illumination systems using incandescent light sources. The document is applicable to both discharge forward lighting systems, subsystems and components. This document is intended to be a guide to standard practice and is subject to change to reflect additional experience and technical advances.

This SAE Recommended Practice is intended as the definition of a standard test, which may be subject to frequent change to keep pace with experience and technical advances. This should be kept in mind when considering its use. This SAE No. 2 friction test monitors the µ-v curve for a negative slope which can be used to evaluate a wet clutch system (WCS) anti-shudder performance and can be used for any wet driveline mechanism. WCS shudder is considered a clutch failure condition. The cause of shudder is consistent with glazing as the primary failure mode. It has been shown that a substantial loss of the wet friction material surface porosity leads to a glaze forming on the friction material surface. This process typically leading to a negative dµ/dv slope over time as addressed in SAE 2020-01-0560.

Since it is impossible to be all inclusive and cover every aspect of the design/validation process, this document can be used as a basis for preparation of a more comprehensive and detailed plan that reflects the accumulated “lessons learned” at a particular company. The following areas are addressed in this document: 1 Contemporary perspective including common validation issues and flaws. 2 A Robustness validation (RV) process based on SAE J1211 handbook and SAE J2628. 3 Design checklists to aid in such a RV process.

This SAE Information Report is specific to integration of rechargeable energy storage systems (RESS) into electrification of buses of all types which comprehends safety, performance, life, etc., utilizing worldwide standards and regulations as references in order to maximize existing work. This document applies to both purpose-built electric buses and retrofit electrified buses at an original equipment manufacturer (OEM). This document does not comprehend retrofitting of buses outside the OEM manufacturing environment.

Conventional resource conservation for automotive traction and its utilization to maximize efficiency is not only important but also essential for climate change. Diesel engine lubricating oil is one such component, which has enough potential considering the current methods of servicing. Present work is focused on developing/validating a process, which can predict critical properties of oil at any given instance. This prediction is independent of vehicle operating conditions and vehicle mileage. As the process is independent of above two parameters, even the oil quality after a top up can be identified.

Today’s vehicles provide a wide range of functions. Some offer comfort support for driving scenarios and others offer a higher level of safety to the driver. Increasing complex systems drives the need for reliable engineering to avoid or at least detect and mitigate malfunctions which would lead to any person being injured. Following state of the art for definition, design, and implementation of any system must therefore always be the target. The need to meet stringent safety requirements of the ISO 26262 Standard is presenting new challenges. In particular, the solutions must ensure that automotive electronic systems always operate safely throughout the vehicle life cycle. Functional safety relies on the safety mechanisms within the design that monitor and verify the correct functional operation of the design while the system is in use. The ability of these safety mechanisms to cover the potential faults determines the overall diagnostic coverage of the design.

Automotive wheel bearings have primary functions of translating the rotating motion of the wheels into vehicle motion while bearing the vehicle weight. The life of automotive wheel bearings can be divided into raceway life and flange life. Of the two lives, flange life is the failure mode in which the wheel flanges begin to fail. The wheel flange life can be numerically predicted through fatigue analysis. Flange fatigue life requires analysis including rotation due to the bearing characteristics. Therefore, flange life evaluation of wheel bearings can be identified through actual road load test data by mounting wheel bearings on actual vehicles. This paper discusses a fatigue analysis method for automotive wheel bearings using actual road load test data to calculate wheel flange life. Stress analysis and fatigue analysis were performed sequentially using commercial software.

High-performance vehicle wheel bearings experience high lateral loading during racetrack testing. Due to higher loads, the wheel bearings are more susceptible to structural and or preload failures. Structural failures can occur in the hub flange, spline and/or roll form. The increased loading and cycling requirements, drives the need to adjust historical evaluation methods. The wheel bearing design for a high-performance vehicle must find the optimum balance between strength, drag, packaging, and mass. The objective of this paper is to cover the methodology to evaluate wheel bearings using the predicted loads before the actual vehicle testing. Initially, the predicted load data consists of many data points and is not suitable for either CAE analysis and/or physical testing.

This SAE Standard covers equipment used to remove contaminated R-134a and/or R-1234yf refrigerant from mobile air conditioning (MAC) systems.