Browse Topic: Failure modes and effects analysis (FMEA)

Items (759)
ABSTRACT Implementing Prognostic and Predictive Maintenance (PPMx) for the U.S. Army’s ground vehicle fleet requires the design and integration of on-platform predictive analytics. To support the design process, U.S. Army DEVCOM Ground Vehicle Systems Center (GVSC) and Applied Research Laboratory (ARL) Penn State researchers are developing a systematic approach that uses reliability modeling in a guiding role. The key steps of the process are building the initial reliability model from available data (e.g., system diagrams and physical layouts), augmenting with information on observed states and failure modes via subject matter experts, and then conducting trades on additional sensors and algorithms to determine a suitable predictive analytics capability. In this paper we provide an example of this process as applied to an Army ground vehicle, first focusing on a simplified sub-problem to demonstrate the technique, then providing statistics on the large scale process. Citation: M
Majcher, MonicaBennett, Lorri A.Banks, JeffreyLukens, MatthewNulton, EricYukish, Michael A.Merenich, John J.
ABSTRACT Structural optimization efforts for blast mitigation seek to counteract the damaging effects of an impulsive threat on critical components of vehicles and to protect the lives of the crew and occupants. The objective of this investigation is to develop a novel optimization tool that simultaneously accounts for both energy dissipating properties of a shaped hull and the assembly constraints of such a component to the vehicle system. The resulting hull design is shown to reduce the blast loading imparted on the vehicle structure. Component attachment locations are shown to influence the major deformation modes of the target and the final hull design
Tan, HuadeGoetz, JohnTovar, AndrésRenaud, John E.
ABSTRACT Acceptance testing is considered a final stage of validation, and performing acceptance tests of an actual UGV system can be expensive and time-consuming. Therefore, this paper discusses simulation based acceptance testing for UGVs, which can significantly reduce the time and cost of the acceptance test. In this paper, both dynamic and static simulation models are developed, and the results from these simulations show that the static simulation can be used, rather than the more complex dynamic simulation, because of the slow operating speed of UGVs. This finding improves the development efficiently at the simulation model development phase. In addition, the developed simulation models provide a better understanding of the UGV failure modes. The static simulations can determine the required joint motor torques for various UGV loadings and maneuvers and provide data for the full range of operating motion. Specifically, given threshold joint torque value, the safe operating range
Lee, Hyo JongJin, Jionghua (Judy)Ulsoy, A. Galip
ABSTRACT Camber Corporation, under contract with the TACOM Life Cycle Management Command Integrated Logistics Support Center, has developed an innovative process of data mining and analysis to extract information from Army logistics databases, identify top cost and demand drivers, understand trends, and isolate environmental issues. These analysis techniques were initially used to assess TACOM-managed equipment in extended operations in Southwest Asia (SWA). In 2009, at the request of TACOM and the Tank Automotive Research, Development and Engineering Center (TARDEC), these data mining processes were applied to four tactical vehicle platforms in support of Condition Based Maintenance (CBM) initiatives. This paper describes an enhanced data mining and analysis methodology used to identify and rank components as candidates for CBM sensors, assess total cost of repair/replacement and determine potential return on investment in applying CBM technology. Also discussed in this paper is the
Ortland, Richard J.Bissonnette, Lee A.Miller, Douglas R.
ABSTRACT Protection Engineering Consultants (PEC) has performed static and dynamic-pendulum tests on bolted and welded connection sub-assemblies to generate data for development and validation of modeling approaches capable of accurately predicting the behavior of connections exposed to shock loads. The connections consisted of Rolled Homogeneous Armor (RHA) steel plates, Grade 8 bolts, and fillet welds of ER80-S wire, as typically used in armored vehicles. A summary of the forty physical tests on nine connection configurations are provided along with strain gage and Digital Image Correlation (DIC) data. The specimens were designed to have typical failure modes, i.e. bolt shear, plate tear-out, and weld shear fracture. Using these data, high-fidelity numerical models were developed, with exceptionally good comparisons to the experimental data. During the development of the numerical models, crucial modeling parameters were identified and were shown to have significant influence to the
Hadjioannou, MichalisBarsotti, MattSammarco, EricStevens, David
ABSTRACT In light of the cancellation of MIL-STD 1629A on 4 August 1998 with no superseding document, this paper outlines the tailoring of an effective industry tool for risk identification and prioritization that will lead to more reliable weapon systems for the warfighter, with reduced total ownership costs. The canceled MIL-STD 1629A used Failure Mode Effects and Criticality Analysis (FMECA) which is similar in method to FMEA but with an added factor called Criticality for prioritization. In FMEA approach, criticality is addressed by the Risk Priority Number (RPN) and other ways to prioritize risk beyond those single criteria. Tank Automotive Research Development and Engineering Center (TARDEC), Systems Engineering Group (SEG) has tailored the FMEA’s Severity, Occurrence, and Detection ranking tables to suit DOD Systems by developing an additional scale (1 – 5) for severity and occurrence parameters for the existing industry scale (1 – 10). This will facilitate transitioning risks
Rizk, Kadry
ABSTRACT This paper identifies the failure modes of military track bushings during lab testing and looks at correlation of lab tests failure modes with those found in field testing failures. In an effort to understand and duplicate the failures seen in the field, a track shoe was modified to measure the displacement (magnitude and direction) of the bushing pin relative to the inside diameter of the track shoe bore. Utilizing Hall Effect Technology and a small data acquisition system, test course data was recorded and analyzed. A specially designed bushing test machine, capable of testing the entire track pitch, was also designed and built in order to duplicate the field failure in a laboratory environment
Gruenberg, ScottBradley, ScottGentner, StephenOstberg, David
ABSTRACT The functionality of the next-generation Department of Defense platforms, such as the Small Unmanned Ground Vehicles (SUGV) and Small Unmanned Arial Vehicles (SUAV), requires strongly electronics-rich architectures. The reliability of these systems will be dependent on the reliability of the electronics. These electronic systems and the critical components in them can experience extremely harsh thermal and vibrations environments. Therefore, it is imperative to identify the failure mechanisms of these components through experiments and simulation based on physics-of-failure methods. One of the key challenges in recreating life-cycle vibration conditions during design and qualification testing in the lab is the re-creation of simultaneous multi-axial excitation that closely mimics what the product experiences in the field. Currently, there are two common approaches in the industry when testing a prototype or qualifying a product for multi-axial vibration environments. One
Habtour, EdMortin, DavidChoi, CholminDasgupta, Abhijit
ABSTRACT Significant Design for Reliability (DfR) methodology challenges are created with the integration of autonomous vehicle technologies via applique systems in a ground military vehicle domain. Voice of the customer data indicates current passenger vehicle usage cycles are typically 5% or less (approximately 72 minutes of use in a twenty-four hour period) [2]. The time during which vehicles currently lay dormant due to drivers being otherwise occupied could change with autonomous vehicles. Within the context of the fully mature autonomous military vehicle environment, the daily vehicle usage rate could grow to 95% or more. Due to this potential increase in the duty or usage cycle of an autonomous military vehicle by an order of magnitude, several issues which impact reliability are worth exploring. Citation: M. Majcher, J. Wasiloff, “New Design for Reliability (DfR) Needs and Strategies for Emerging Autonomous Ground Vehicles”, In Proceedings of the Ground Vehicle Systems
Majcher, MonicaWasiloff, James
ABSTRACT This research paper addresses the ground vehicle reliability prediction process based on a new integrated reliability prediction framework. The paper is an extension of the paper presented last year at the GVSETS symposium. The integrated stochastic framework combines the computational physics-based predictions with experimental testing information for assessing vehicle reliability. The integrated reliability prediction approach incorporates the following computational steps: i) simulation of stochastic operational environment, ii) vehicle multi-body dynamics analysis, iii) stress prediction in subsystems and components, iv) stochastic progressive damage analysis, and v) component life prediction, including the effects of maintenance and, finally, iv) reliability prediction at component and system level. To solve efficiently and accurately the challenges coming from large-size computational mechanics models and high-dimensional stochastic spaces, a HPC simulation-based
Ghiocel, Dan M.Negrut, DanLamb, DavidGorsich, David
ABSTRACT Program offices and the test community all desire to be more efficient with respect to testing but currently lack the analytical tools to help them fit early subsystem level testing into a framework which allows them to perform assessments at the system level. TARDEC initiated a Small Business Innovative Research (SBIR) effort to develop and deploy a system reliability testing and optimization tool that will quantify the value of subsystem level tests in an overall test program and incorporate the results into system level evaluations. The concept software, named the Army Lifecycle Test Optimization (ALTO) tool, provides not only the optimization capability desired, but also other key features to quickly see the current status, metrics, schedule, and reliability plots for the current test plan. As the user makes changes to the test plan, either by running the optimization or adjusting inputs or factors, the impacts on each of these areas is computed and displayed
Luna, JoelSnider, SharonBrudnak, MarkLaRose, BryanMorgan, MelissaKosinski, DanScott, Mike
ABSTRACT Solid oxide fuel cell (SOFC)-based auxiliary power units (APUs) offer a quiet and efficient platform for remote power generation. SOFC systems often utilize a reformer subsystem which converts hydrocarbon fuels into a hydrogen-rich effluent stream utilized by the fuel cell stack for electrical power generation. Rochester Institute of Technology’s Center for Sustainable Mobility (RIT / CSM) has conducted research to analyze potential system failures and develop accelerated durability protocols for SOFC systems. Based on this experimental and analytical study, it has been shown that solid carbon formed during fuel reformation is quantifiable, predictable, and affects SOFC system durability. RIT / CSM further developed accelerated durability protocols for SOFC carbon related failure modes, utilizing carbon concentration measurements from SOFC systems combined with post-processing of system operational parameters. Fully integrated SOFC systems were employed to generate a
Walluk, Mark R.Smith, Daniel F.Trabold, Thomas A.Dewey, Scott B.
ABSTRACT Problem: The traditional four (4) methods for improving reliability; 1) High design safety margin, 2) Reduction in component count or system architectural complexity, 3) Redundancy, and 4) Back-up capability, are often ignored or perceived as being excessively costly in weight, space claim as well as money. Solution 1: Discussed here are the practical and very cost effective methods for achieving improved reliability by Functional Interface Stress Hardening (FISHtm or FISHingtm). The Author has been able to apply FISH to eliminate 70-92% of unscheduled equipment downtime, within 30-60 days, for more than 30 of the Fortune 500 and many other large companies which utilize automation controls, computers, power electronics and hydraulic control systems. Solution 2: From Structured Innovation the 33 DFR Methods & R-TRIZ Tool can be used to grow or improve reliability, via rapid innovation. The R-TRIZ tool) is provided so that users can instantly select the best 2, 3 or 4 of these
Cooper, Howard C
ABSTRACT In today’s competitive market, OEMs are racing towards developing more efficient vehicles without sacrificing on its performance. In this process, they’re forced to evaluate new technologies and designs in various subsystems. Most of the sub-systems today have become “intelligent”, which means that the controllers have become quintessential for the system’s behavior. Equally important are the physical behavior of the plant that needs to be controlled. These two independent groups have their own design and development cycle and the challenge for the companies have been in bridging the gap so as to identify potential failure modes. This paper discusses an Architecture-driven Model Based Development process that can address the challenges posed during the development. Three key enabling technologies – Imagine.Lab System Synthesis, Imagine.Lab SysDM & Imagine.Lab AMESim are leveraged in this process
Radhakrishnan, KarthikeyanPadmanaban, RameshPaike, RavindraVijay, Hari
Abstract This paper presents a fault-tolerant powertrain topology for series hybrid electric vehicles (SHEVs). The introduction of a redundant phase leg that is shared by three converters in a standard SHEV drive system allows to maximize the reliability improvement with minimal part-count increase. The new topology features fast response in fault detection and isolation, and post-fault operation at rated power throughput. The operating principle, control strategy, and fault diagnostic methods are elaborated. The substantially improved reliability over the standard topology is verified by the Markov reliability model. Time-domain simulation based on a Saber model has been conducted and the results have verified the feasibility and performance of the proposed SHEV drive system with fault-tolerant capability. The experimental results from a prototype have further validated the robust fault detection scheme and excellent post-fault performance
Song, YantaoWang, Bingsen
ABSTRACT High life cycle costs coupled with durability and environmental challenges of tracked vehicles in South West Asia (SWA) have focused R&D activities on understanding failure modes of track components as well as understanding the system impacts on track durability. The durability limiters for M1 Abrams (M1, M1A1, and M1A2) T-158LL track systems are the elastomeric components. The focus of this study is to review test methodology utilized to collect preliminary data on the loading distribution of a static vehicle. Proposed design changes and path forward for prediction of durability of elastomers at the systems level from component testing will be presented
Ostberg, DavidBradford, Bill
ABSTRACT All CBM+ solutions must establish a business case considering cost of implementation and sustainment of value with a quantifiable return on investment. The business case must be traceable to specific failure modes, associated failure effects, criticality, and risk. Risk is not limited to safety and operational risks. Predictive systems by definition return both true and false predictions representing operational and financial risk from high false positive rates. There is also risk of losing operator confidence in predictive systems when there is a high false positive rate. All of these risks must be quantified and considered in the design and development of CBM+ systems. Model based approaches are effective in accelerating development, defining advanced functional characteristics, and efficiently testing dynamic effects of complex systems. CBM+ maintenance strategies rely on performance of complex systems
Nelson, DavidBanghart, Marc
ABSTRACT In this work, Abrams tank track system T-158LL backer pad elastomer self-heating and fatigue behavior was characterized experimentally, and the backer pad design was digitally twinned to show how complex in-service conditions can be evaluated virtually. The material characterization included measurement of the thermal properties and dissipative characteristics of the rubber compound, as well as its fatigue crack growth rate curve and crack precursor size. The analysis included 1) a structural finite element analysis of the backer pad in operation to obtain the load history, 2) a thermal finite element analysis to obtain steady-state operating temperature distribution within the backer pad, and 3) a thermo-mechanical fatigue analysis using the Endurica CL fatigue solver to estimate the expected service life and failure mode of the backer pad. As validation, experiments were conducted on the backer pad to measure operating temperature, fatigue life, and failure mode over a
Mars, William V.Castanier, MatthewOstberg, DavidBradford, William
ABSTRACT Situation: There are many advantages during development of a design that come from doing Design Failure Mode Effects Analysis (DFMEA). These advantages include more reliable, safer, self-diagnosing, designs with higher Availability. Strictly from a Design for Reliability (DFR) viewpoint, DFMEA is the key tool to; a. identify and prioritize most critical potential Failure Modes (FMs) of the design, before design development, b. Document critical FM effects and root causes, and c. facilitate corrective actions and DVP&R planning, and d. form a reliability model which can be used to track reliability over the life of the design. Problem: Since even small and simple designs often have a few hundred potential failure modes, preparing a good DFMEA is always a problem of Effectiveness vs., Efficiency. Traditionally it has been very hard to achieve Effectiveness when limited time, money and resources are available and the push for Efficiency, speed or deadlines, causes critical FMs to
Cooper, Howard CTananko, DmitryShutek, J. Gordon
ABSTRACT Vehicle prognostics are used to estimate the remaining useful life of components or subsystems, based on a limited number of measured vehicle parameters. Ideally, sensors would be available for every component and failure mode of interest, such that accurate data could be measured and used in prognostic estimates. However, this is impractical in terms of the number of sensors required and the costs to install such a system and maintain its integrity. A better solution is to relate the loading on a specific component to more generic vehicle behavior. This paper reviews a methodology referred to as the “Durability Transfer Concept”, which suggests that damage, or severity of usage, at various points of interest on a vehicle can be predicted simply from measured accelerations at some nominal location – a wheel axle, for example. Measured accelerations are double integrated to get displacements. Those displacements are then filtered using the Rupp or Lalanne method. A transfer
Halfpenny, AndrewHussain, ShabbirMcDougall, ScottPompetzki, Mark
Transit agencies around the world have been investing in more battery electric buses (BEB) in an effort to combat the growing negative externalities stemming from the use of petrochemicals in combustion transit vehicles. These buses use new propulsion systems based primarily on lithium-ion batteries to cut carbon pollution and promote cleaner, faster, and safer rides. As new electrification technologies continue to penetrate the bus transit market, there is a continuous need to evaluate the safety and performance of these battery electric systems. To meet the safety and performance needs of technologies in transit buses, regulations and standards have been established to define best testing and industry practices. This paper details the current state of battery standards and regulations in automotive and transit vehicles, with consideration of battery failure modes and effects. Various governments and standard organizations have established numerous different regulations and standards
Jankord, GregoryGravante, EmanueleD'Arpino, Matilde
This SAE Aerospace Standard (AS) defines the requirements for air cycle air conditioning systems used on military air vehicles for cooling, heating, ventilation, and moisture and contamination control. General recommendations for an air conditioning system, which may include an air cycle system as a cooling source, are included in MIL-E-18927E and JSSG-2009. Air cycle air conditioning systems include those components which condition high temperature and high pressure air for delivery to occupied and equipment compartments and to electrical and electronic equipment. This document is applicable to open and closed loop air cycle systems. Definitions are contained in Section 5 of this document
AC-9 Aircraft Environmental Systems Committee
In the rapidly evolving landscape of electronic engineering, the reliability of electronic components under varying thermal conditions has emerged as a paramount concern. This paper presents an integrated approach for the reliability analysis of electronic components, emphasizing thermal impacts. Our methodology synergizes computational thermal analysis, experimental stress testing, and Failure Modes, Effects, and Diagnostic Analysis (FMEDA) to offer a comprehensive framework for assessing and enhancing component reliability, specifically focusing on a case study of motorcycle hand control switches. The approach begins with a detailed thermal simulation to identify potential hot spots and thermal gradients across electronic components under different operational scenarios. For the case study, motorcycle hand control switches a critical interface between the rider and the motorcycle's electrical system were subjected to this analysis to predict thermal behavior under varied
Mote, ShwetaJadhav, ShantaramChaudhari, VijayMhaske, Aashay
The purpose of air conditioning (AC) duct packing is multifaceted, serving to prevent condensation, eliminate rattle noise, and provide thermal insulation. A critical aspect of duct packing is its adhesive quality, which is essential for maintaining the longevity and effectiveness of the packing's functions. Indeed, the challenge of achieving adequate adhesivity on AC ducting parts is significant due to the harsh operating conditions to which these components are subjected. The high temperatures and presence of condensation within the AC system can severely compromise the adhesive's ability to maintain a strong bond. Moreover, the materials used for these parts, such as HDPE, often have low surface energy, which further hinders the formation of a durable adhesive bond. The failure of the adhesive under these conditions can lead to delamination of the duct packing, which can result in customer inconvenience due to rattling noises, potential electrical failures if condensed water
M, Amala RajeshSonkar, SurabhiKumar, Mukesh
Geared automotive and aerospace transmissions are one of the most critical systems regarding wear. Limiting wear is of paramount importance to improve sustainability by reducing replacements that lead to increased waste and energy consumption for re-manufacturing. Simulation of gears including the wear effect can be very useful for the design of new more efficient and compact gears. Thermal effects may play a decisive role in the wear phenomena and should be included in the models used for simulations. In this study, some tests are conducted on a pin-on-disk apparatus under varying temperatures to assess its influence on steel-to-steel wear rate. A modified Archard law is used for wear estimation which includes the experimentally derived parameters accounting for thermal effects. This model is then coupled with a loaded tooth contact analysis (LTCA) tool to obtain accurate predictions of the contact pattern, as well as the instantaneous load shared by the mating teeth pairs during the
Grabovic, EugeniuCiulli, EnricoArtoni, AlessioGabiccini, Marco
This standard defines requirements for the identification, assessment, mitigation, and prevention of risk in the manufacturing process through the application of Process Flow Diagrams (PFDs), Process Failure Mode and Effects Analysis (PFMEA) and Control Plans throughout the life cycle of a product. This standard aligns and collaborates with the requirements of AS9100, AS9102, AS9103, and AS9145. The requirements specified in this standard apply in conjunction with and are not alternative to contractual and applicable statutory and regulatory requirements. In case of conflict between the requirements of this standard and applicable statutory or regulatory requirements, the latter shall take precedence
G-22 Aerospace Engine Supplier Quality (AESQ) Committee
Rolling bearings play a critical role in rotating machinery, with their fatigue life directly impacting equipment’s operational reliability. This underscores the significant engineering application value of “fault diagnosis” (FD) technology for rolling bearings in mechanical, automation, and aerospace domains. Literature reviews highlight that a substantial portion of failures in machinery such as jet turbine engines, wind turbines, gear reducers, and induction machines are attributable to bearing issues. Early fault detection and preventive maintenance are therefore imperative for ensuring the smooth operation of rotating machinery. This paper focuses on rolling bearings, delving deep into FD technology using machine learning principles. It analyses the structure and common failure modes of rolling bearings, discussing an FD method based on machine learning. Specifically, the SE-DRN (“squeeze-exclusion deep residual network”) approach is employed, leveraging “variational modal
Muin, Abdullah-AlKhan, ShahrukhMiah, Md Helal
With the increasing demand of human–machine interaction under a scenario of the novel Maintenance Strategy 5.0, it sparks off a growing requisition of reliable maintenance strategies to maintain operations in good order. In this study, a novel hierarchical maintenance strategy model based on multi-criteria decision analysis (MCDA) is proposed to pledge scientific maintenance. First, failure mode and effects analysis (FMEA) based on negative information and Deng entropy is introduced to assess the equipment maintenance requirement level. Subsequently, the improved average rank method is selected to fit the Weibull distribution function, which is able to better qualify the characteristics lifespan of target equipment. Moreover, hybrid effect with multi-criteria decision-making, in aspects of risk priority, expert assessment as well as human interference of failure are deduced, which highlights the scientific significance and credibility of the recommended maintenance levels and times
Wei, MingxinPan, ZheshengWang, ChengxiangMa, ZexinLi, GuoxiangZhao, FeiyangYu, WenbinZhu, Sipeng
Verification and validation (V&V) is the cornerstone of safety in the automotive industry. The V&V process ensures that every component in a vehicle functions according to its specifications. Automated driving functionality poses considerable challenges to the V&V process, especially when data-driven AI components are present in the system. The aim of this work is to outline a methodology for V&V of AI-based systems. The backbone of this methodology is bridging the semantic gap between the symbolic level at which the operational design domain and requirements are typically specified, and the sub-symbolic, statistical level at which data-driven AI components function. This is accomplished by combining a probabilistic model of the operational design domain and an FMEA of AI with a fitness-for-purpose model of the system itself. The fitness-for-purpose model allows for reasoning about the behavior of the system in its environment, which we argue is essential to determine whether the
Paardekooper, Jan-PieterBorth, Michael
The modern automotive industry is facing challenges of ever-increasing complexity in the electrified powertrain era. On-board diagnostic (OBD) systems must be thoroughly calibrated and validated through many iterations to function effectively and meet the regulation standards. Their development and design process are more complex when prototype hardware is not available and therefore virtual testing is a prominent solution, including Model-in-the-loop (MIL), Software-in-the-loop (SIL) and Hardware-in-the-loop (HIL) simulations. Virtual prototype testing relying on real-time simulation models is necessary to design and test new era’s OBD systems quickly and in scale. The new fuel cell powertrain involves new and previously unexplored fail modes. To make the system robust, simulations are required to be carried out to identify different fails. Thus, it is imminent to build simulation models which can reliably reproduce failures of components like the compressor, recirculation pump
Pandit, Harshad RajendraDimitrakopoulos, PantelisShenoy, ManishAltenhofen, Christian
The Aerospace Industry's drive towards zero defects has seen a significant shift to prevent defects and improve product quality during the design phase, instead of waiting until post-production inspection to discover and troubleshoot problems. Trying to ensure zero defects during the post-production inspection phase is too late in the product life cycle because it can lead to substantial costs. Aerospace Engine Supplier Quality (AESQ) introduced the Advanced Product Quality Planning (APQP) [2] process to realize zero defects. In APQP Phase 2 [2], Product and Design Development, a key output is performing a Design Failure Modes and Effects Analysis (DFMEA). Moog has effectively implemented a DFMEA process that adeptly identifies and mitigates design risks. This work showcases Moog's successful deployment of DFMEA, exemplifying the industry best practices. This work also presents simplified and innovative interpretations of DFMEA definitions and approaches. By addressing defects during
Shah, AchintShea, RachelleSiskowski, Bruce
Hydraulic systems in aircraft largely comprise of metallic components with high strength to weight ratios. Some examples of such material include Aluminum and Titanium alloys which are typically chosen for low and high-pressure applications respectively. For aircraft fluid conveyance products, hydraulic conduits are fabricated by axisymmetric turning to support flow conditions. The hydraulic conduits can have grooved interfaced design within for placement of elastomeric sealing components. This article presents a systematic study carried out on common loads experienced by fluid carrying conduits and the failure modes induced. Firstly, a static structural analysis was carried out on each of the geometries of the test articles to identify the locations having areas of high stress concentration. Test articles of various wall thicknesses and internal diameters were pressure impulse tested at different conditions of side loads to identify cycle numbers till failure and failure locations. On
Paidimarri, VishalJacob, KrupaHarish, UppuHovis, David
Thermo-mechanical fatigue and natural aging due to environmental conditions are challenging to simulate in an actual test with advanced fiber-reinforced composites, where their fatigue and aging behavior are little understood. Predictive modeling of these processes is challenging. Thermal cyclic tests take a prohibitively long time, although the strain rate effect can be scaled well for accelerating the mechanical stress cycles. Glass fabric composites have important applications in pipes, aircraft, and spacecraft structures, including microwave transparent structures, impact-resistant parts of the wing, fuselage deck and many other load-bearing structures. Often additional additively manufactured features and coatings on glass fabric composites are employed for thermal and anti-corrosion insulations. In this paper, we employ a thermo-mechanical fatigue model based on an accelerated fatigue test and life prediction under hot-to-cold cycles. Thermo-mechanical strain-controlled stress
Kancherla, Kishore BabuB S, DakshayiniRaju, BenjaminRoy Mahapatra, Debiprosad
With globalization, vehicles are sold across the world throughout different markets and their automotive brake systems must function across a range of environmental conditions. Currently, there is no current standardized test that analyzes brake pads’ robustness against severe cold and humid environmental conditions. The purpose of this proposed test method is to validate brake system performance under severe cold conditions, comparing the results with ambient conditions to evaluate varying lining materials’ functional robustness. The goal of this paper is to aid in setting a standardized process and procedure for the testing of automotive brakes’ environmental robustness. Seven candidate friction materials were selected for analysis. The friction materials are kept confidential. Design of experiment (DOE) techniques were used to create a full-factorial test plan that covered all combinations of parameters. The test script involves brake applications at 5, 10, 15, and 20 bar, at both
Passador, Stephen Daniel AustinBoudreau, Douglas BarretCapacchione, Christopher James
The qualification requirements of automakers derive from track testing in which road load and moment inputs to a part in x, y and z directions are recorded over a set of driving conditions selected to represent typical operation. Because recorded histories are lengthy, often comprising many millions of time steps, past industry practice has been to specify simplified block cycle schedules for purposes of durability testing or analysis. Simplification, however, depends on imprecise human judgement, and risks fidelity of the inferred life and failure mode relative to actual. Fortunately, virtual methods for fatigue life prediction are available that are capable of processing full, real-time, multiaxial road load histories. Two examples of filled natural rubber ride bushings are considered here to demonstrate. Each bushing is subject to a schedule of 11 distinct recorded track events. Endurica EIETM map building procedures are first used together with a finite element solution to map the
Mars, WilliamBarbash, KevinWieczorek, MatthewBraddock, ScottGoossens, JoshuaSteiner, Ethan
Validation of powertrain systems is nowadays performed with specific durability relevant load cycles, which represent the lifetime requirement of individual powertrain components. The definition of such durability relevant load cycles, which are used for vehicle testing should ideally be based on the actual vehicle's usage. Recording driving cycles within a vehicle is one of the most typical ways of collecting vehicle usage and relevant end customer behavior, but the generation of such measured vehicle data can be time consuming. In addition, this method of capturing on-road measurements has limitations in the variation of vehicle loadings (e.g., number of passengers, luggage, trailer usage etc.). Especially for new applications, entering new target markets, these kinds of in-vehicle measurements are not possible in early development stages, as the required vehicle or powertrain configuration is not available in hardware or incapable of measurements. This paper shows a method to
Haspl, AndreasUnterweger, MichaelaKuruc, JanPlettenberg, MirkoAkasapu, Uday Venkateswar
Complex chassis systems operate in various environments such as low-mu surfaces and highly dynamic maneuvers. The existing metrics for lateral motion hazard by Neukum [13] and Amberkar [17] have been developed and correlated to driver behavior against disturbances on straight line driving on a dry surface, but do not cover low-mu surfaces and dynamic driving scenarios which include both linear and nonlinear region of vehicle operation. As a result, an improved methodology for evaluating vehicle yaw dynamics is needed for safety analysis. Vehicle yaw dynamics safety analysis is a methodical evaluation of the overall vehicle controllability with respect to its yaw motion and change of handling characteristic. The yaw dynamics safety analysis is crucial for understanding how a driver-vehicle system responds to disturbances (external forces such as failure modes) in various driving scenarios and maneuvers., and it plays a significant role in evaluating the overall safety and performance of
paik, ScottAlmasri, HossamRao Medidha, NeelakantaCapobianco, AnthonyEvans, AndrewSevillano, Yvette
The paper introduces two methods for controlling motor voltage. One method requires the implementation of boost hardware, while the other allows for voltage control in battery failure mode without any additional hardware requirements. The boost voltage strategy for the hybrid system is based on managing boost modes, determining target voltages, and implementing PI control. The boost mode control includes different modes such as initial mode, normal mode, shutdown mode, and fault mode. Determining the boost target voltage involves regulating the boost converter with variable voltages depending on the operating states of the motor and generator. The second voltage control method without boost hardware is proposed in order to ensure that the vehicle can still function like a traditional car even under abnormal conditions of high-voltage battery failure in micro-mixing systems. In this mode, instead of conventional torque control, the generator operates in a voltage control mode where
Jing, JunchaoSun, XudongLiu, YiqiangHuang, Weishan
Steer-By-Wire (SBW) system directly transmits the driver's steering input to the wheels through electrical signals. However, the reliability of electronic equipment is significantly lower than that of mechanical structures, and the risk of failure increases, so it is important to conduct functional safety studies on SBW systems. This paper develops the functional safety of the SBW system according to the requirements of the international standard ISO26262, and first defines the relevant items and application scope of SBW system. Secondly, the Hazard and Operability (HAZOP) method was used to combine scenarios and possible dangerous events to carry out Hazard Analysis and Risk Assessment (HARA), and the Automotive Safety Integrity Level (ASIL) was obtained according to the three evaluation indicators of Exposure, Severity and Controlabillity, and then the corresponding safety objectives were established and Fault Tolerant Time Interval (FTTI) was set. Finally, the safety analysis of the
Li, AohanKaku, ChuyoWang, ZhenhuaZheng, Hongyu
Lithium-ion batteries serve as the main power source for contemporary electric vehicles. Safeguarding these batteries against damage is paramount, as it can trigger accelerated performance deterioration, potential fire hazards, environmental threats, and more. This study explores damage progression of a commercial vehicle lithium-ion battery module containing prismatic cells under indentation crush loading. We employed computational simulations of mechanical loading tests to investigate this behavior. Physical tests involved subjecting modules to low-speed (0.05 m/s) indentations using a V-shaped stainless-steel wedge, under six unique loading conditions. During the tests, force, and voltage change with wedge displacement were monitored. Utilizing experimental insights, we constructed a finite element model, which included key components of the battery module, such as the prismatic cells, steel frames, and various plastic parts. The finite element model reproduced failure modes
Zhu, FengLogakannan, KrishnaXu, SidaSypeck, David
The modern luxurious electric vehicle (EV) demands high torque and high-speed requirements with increased range. Fulfilling these requirements gives rise to the need for increased efficiency and power density of the motors in the Electric Drive Unit (EDU). Internal Permanent Magnet (IPM) motor is one of the best suited options in such scenarios because of its primary advantages of higher efficiency and precise control over torque and speed. In the IPM motor, permanent magnets are mounted within the rotor body to produce a resultant rotating magnetic field with the 3-phase AC current supply in the stator. IPM configuration provides structural integrity and high dynamic performance as the magnets are inserted within the rotor body. Adhesive glue is used to install the magnets within the laminated stack of rotor. High rotational speed of rotor introduces centrifugal loading on the magnets which can result in multiple failure modes such as the debonding of the magnet, and high radial
Karmakar, NilankanP, PraveenGoel, Ashish
In the aerospace industry, large aircrafts employ composite materials for making complex structures which not only reduces weight and cost but also reduces the number of joints. Irrespective of that joining of structures cannot be avoided and for that mechanical fasteners such as rivets and bolts are employed along with adhesive bonding. Further, in recent years natural fibers have been studied extensively for their numerous advantages and have already been made into several automotive applications. Keeping these current trends in mind an attempt is made to investigate the joining behavior of natural fiber composites experimentally. So in this study, the ultimate failure load, bearing strength and the dominating failure mode of jute-hemp fabric-reinforced polymeric composites joined using single and double-bolted configurations are studied. The polymeric composite laminates were successfully fabricated using resin infusion technique and test specimens were fabricated following ASTM
Koppad, PraveennathChinnakurli Suryanarayana, RameshReddy, NagarajaSethuram, D
The global electric and hybrid aircraft market utilizing lithium-ion Energy Storage Systems (ESS) as a means of propulsion, is experiencing a period of extraordinary growth. We are witnessing the development of some of the most cutting-edge technology, and with that, some of the most complex challenges that we as an industry have ever faced. The primary challenge, and the most critical cause of concern, is a phenomenon known as a “Thermal Runaway”, in which the lithium-ion cell enters an uncontrollable, self-heating state, that if not contained, can propagate into a catastrophic fire in the aircraft. A Thermal Runaway (TR) can be caused by internal defects, damage, and/or abuse caused by an exceedance of its operational specifications, and it is a chemical reaction that cannot be stopped once the cell has reached its trigger temperature. There are many technical papers that explore the characteristics of battery cells and the TR as a failure mode, but the failure mechanism(s) are still
Hanna, MichaelWalker, Cherizar
Airworthiness Directives (ADs) serve as a medium through which commercial and military regulators improve the system’s performance by responding to the failure of the airplanes. The Federal Aviation Administration (FAA) and United States Air Force (USAF) provide ADs that detail overall cost on operators. The dataset derived from the Boeing 767 (B767) and its military derivatives, USAF’s KC-46A gives ideas into sensor solutions and maintenance approaches that may reduce these costs. Given the ADs significant costs for Boeing 767 operations, an analytical failure framework that determines the failure modes and failure mechanisms is introduced. For example, a huge portion of severe impairment (e.g., cracking, corrosion, and chafing) constitutes 27% of failure mechanisms in these systems. To reduce future B767 ADs for commercial and military operators, sensor solution and maintenance strategies using performance metric and genetic algorithm are assessed. As a result, maintenance downtimes
Rasaq, LukmonFerguson, KorbinYadav, OmKyle, BlondSiddula, Madhuri
Aluminium composites are remarkably used in automotive, aerospace, and agricultural sectors because of their lightweight with definable mechanical properties. The stir casting route was followed to fabricate cylindrical samples with base aluminium alloy LM4, LM4/SiC, LM4/Al2O3, and LM4/SiC/Al2O3. The tensile strength, compressive strength, hardness, and micro-structural analysis were performed on samples and Finite element analysis (FEA) was adopted to predict the failure modes of composites. The composites experimental results were found to be in line with the FEA results, however, the LM4/SiC/Al2O3 revealed better results on the mechanical properties when compared with other composite configurations. The mechanical properties improvement like hardness 5%-11%, tensile strength 10.26%-20.67%, compressive strength 15.19% - 32.58% and 71.52 - 82.1% reduction in dimension have been achieved in LM4/SiC/Al2O3 composite comparing to base metal
Rajeswari, B.Manikandan, C.Rajeshkumar, L.Aravind, R.M.
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