Browse Topic: Quality, Reliability, and Durability

Items (10,233)
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 BAE Systems has departed from traditional design rules of thumb and implemented a full-vehicle durability fatigue life analysis process at the design concept level to support lighter weight component designs. The durability process includes derivation of test duty cycles, generation of virtual loads from vehicle dynamic simulations, cascading of hundreds of channels of suspension attachment loads, and prediction of accumulated damage/fatigue life for both quasi-static and transient responses using a finite element vehicle structural model. The fatigue analysis process is typically deterministic, however the stochastic nature of the loads, material properties, and build variations should also be considered to ensure a robust durability process. The process is demonstrated on a heavy wheeled-vehicle platform using a generic duty cycle with examples shown at each stage of the process. This study additionally demonstrates the effects of variability of loads, materials, and
Purushothaman, NammalwarJayakumar, ParamsothyCritchley, JamesDatta, SandipPisipati, Venkat
ABSTRACT State-of-the-art Diesel engines used for on-highway operation are integrated systems containing multiple subsystems for performance and emissions enhancements. The drive to lower tailpipe emissions on on-highway engines drives system complexity which is both undesired and unnecessary for military ground vehicles. There are, however, on-highway technologies such as high pressure fuel injection systems and advanced turbocharger systems that allow improving the engines’ efficiency and therefore lowering its fuel consumption. The aforementioned technologies are currently available and present possible near term opportunities for military ground vehicles. The adaptation to allow reliable operation in military vehicles will be discussed as part of this near term view. The authors will also discuss the electronic controls architecture requirements that come along with these sophisticated technologies and discuss the advantages and opportunities that present themselves using advanced
Tatur, MarekTomazic, DeanKoehler, Erik
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
ABSTRACT Systems Engineering (SE) would always benefit from the inclusion of the Six-Sigma perspective in both the planning and execution of project systems. This applies to not only System Engineers but also to Systems Extended Team Members, all who must provide cumulated knowledge along with competency to the project. It is difficult to obtain a high level of competency among single members of the team to be highly successful. Strength in one area is very often an underlying factor of weakness in another area. Determining and integrating sigma characteristics from the development cycle into all remaining phases of the product project, especially at critical component interfaces, with a resultant sigma value given to those connections that develop a sigma-risk factor for each function and process pathway within the operational configuration. This sigma-risk factor concept is the key in uniting knowledge with experience
Maholick, WilliamGodell, Carl J
ABSTRACT Value Engineering (VE) is an organized effort directed at analyzing the function of a product, service, or process to achieve the lowest total cost of effective ownership while meeting the customer’s needs. A comparison as to how VE is applied and to what extent is made between the automotive industry and the Government using the Program Executive Office Ground Combat Systems (PEO GCS) as a standard. Both the automotive industry and the Government use common VE techniques to conduct VE studies. Both use VE to manage functionality to yield value to the customer. Neither the Government nor the automotive industry sacrifices the quality of the product or its reliability in the name of cost. Both the auto industry and the PEO employ a systematic team approach to analyze and improve the value of a product, facility design, system, or service. Applying systems engineering principles helps ensure successful execution of the PEO GCS VE program. The auto industry uses VE more widely
Dmoch, Barbara J.Wiklund, George
ABSTRACT The demand for mobile, secure communications has been and will continue to be a fundamental requirement for dismounted, urban and distributed operations in the field. It is imperative that soldiers on the front lines receive actionable information in a timely, secured and uninterrupted manner to increase force protection and effectiveness. In this paper, we describe a novel, high technical maturity (TRL 8+) communications link that offers the mounted and dismounted soldier secure, beyond line of sight, encrypted capability for weapons control and command & control of multiple platforms. An innovative spread spectrum waveform was designed from the ground up to deliver necessary functionality for reliable communications amongst multiple nodes with a data rate and range commensurate with battlefield scenarios
Mehta, Amish A.Cambridge, AndrewGardner, Brian
ABSTRACT The design of power distribution systems for modern tanks and fighting vehicles involves a number of challenges, including demands for increasing amounts of electrical power. In response to these needs, Solid State Power Controllers (SSPCs) provide a number of advantages over electromechanical circuit breakers and relays. These include increased reliability, higher volume and weight power densities, lower power dissipation, reduced EMI emissions, very rapid short circuit protection, and precise I2t overload protection. The latter protects wiring, loads and the SSPCs themselves against overheating, while reliably avoiding “nuisance trips” when switching into capacitive or incandescent lamp loads. Further, SSPCs provide capabilities in the area of real time feedback, enabling system-level diagnostics and prognostics, and predictive, condition-based maintenance, thereby providing increased availability and continued mission readiness
Glass, Mike
ABSTRACT Modern heavy duty Commercial Off The Shelf (COTS) diesel engines represent the state of the art in engine performance and design features, control architecture, and the use of light weight high strength materials. These engines, with appropriate adaptation for operation on military fuels, make excellent choices for defense applications. This paper reviews the selection and modification of a COTS engine suitable for potential defense applications. Considerations for robust operation of the engine on JP8, engine system modifications appropriate for military vehicle emission requirements, reduction of engine system heat rejection, and optimization of engine efficiency will be discussed using example data from converting a 2011 model year COTS engine for defense applications as funded by Broad Agency Announcement (BAA) Topic 15
Hunter, Gary L.
ABSTRACT Results are presented from tests on a formulated 15W-40 mil-spec engine/transmission fluid to examine the impact of additives on improving its reliability and durability under extreme tribological conditions. A block-on-ring (BOR) configuration was used to measure the effect of five additives (an emulsion-based boric acid, tricresyl phosphate, particulate-based boron nitride, particulate-based MoS2, and particulate-based graphite) on the critical scuffing load as a function of additive concentration and time to scuff during oil-off tests (starved lubrication). A four-ball configuration was used to evaluate the impact of simulated engine grit/sand on the abrasive wear of steel as a function of grit size and loading. The results demonstrated that the additives increased the load for scuffing by 50 to 100% for the formulated oil and by 50 to 150% for the unformulated base fluid used in the formulated oil. Two of the additives (emulsion-based boric acid and tricresyl phosphate
Fenske, G. R.Ajayi, O. O.Erck, R. A.Lorenzo-Martin, C.Masoner, AshleyComfort, A. S.
ABSTRACT This paper will describe layers of open standards, demonstrate the problems of standard top-down requirements flow-down and derivation, and show how the standard Analysis-of-Alternatives, as used at highest levels of Department of Defense acquisition, is appropriate for use at lower levels. Examples of how to (and not to) use open-standards in systems engineering specifications for best commonality and competition will be provided, intended for use as templates in specifications
Jedynak, David
ABSTRACT Today’s battlefield requires access to information in a multitude of environments with varying terrains (both urban and rural) in either passive or active engagements. Ground vehicles need sensors that can be rapidly deployed to different locations and networked into the family of vehicles in order to effectively share information. Masted sensor systems, in particular, are a potential valuable resource with their ability to perform long-range surveillance over obstructions while minimizing vehicle exposure. To maximize effectiveness these systems must withstand harsh battlefield conditions without undue maintenance. The need for variable mast heights, on-the-move (OTM) sensor performance, the ability to support a wide variety of long-range sensors, internal cabling to better resist battlefield damage, resistance to armored vehicle vibration and shock environments, and rapid mast deployment and stowage have driven Lockheed Martin to a robust mast solution that meets this
Neely, DavidFosen, KeithPoteat, DanielCarmichael, D. Brian
ABSTRACT The Integrated Systems Engineering Framework (ISEF) is an Army Research, Development, and Engineering Command (RDECOM) solution to address stovepiped systems engineering(SE) information and processes, disparate tools united by custom, one-off integrations, and a lack of accepted, common standards that exists in today’s Department of Defense (DoD) operating environment. Ever increasing technical complexity of fielded solutions combined with budgetary constraints push DoD engineers to “do more with less,” requiring a technical management solution that allows them collaborate virtually yet effectively with distributed engineers and other stakeholders. Easy access to systems engineering tools and information through a single “cloud” based application allows connections between federated databases, and facilitates knowledge preservation over time to avoid “reinventing the wheel” when new programs replace retired ones. ISEF is an ever-expanding collection of systems engineering
Umpfenbach, EdwardMendonza, PradeepGraf, Lisa
ABSTRACT The integration of software into transportation systems is growing and requires the adoption of safety standards and software development systems. There are several different safety standards that could be applied based on the specific category of use. The basic methodologies used in these standards can be applied to any transportation system including Ground Based systems. This paper evaluates two different safety development standards and provides a high level comparison between a well-used standard for aviation and a more recent standard for automotive that can be applied to other transportations systems with no available standards
Crots, KevinSkentzos, PaulBartz, Dan
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 Leveraging an open standard may still not achieve the desired interoperability between systems. Addressing “lessons learned” from past implementations of open standards for various Department of Defense (DoD) acquisition programs is critical for future success. This paper discusses past issues which range from insufficient technical detail, when and how to apply a given specification, verification of an implementation’s compliance, to inconsistent and imprecise contractual language. This paper illustrates how the Vehicular Integration for C4ISR/EW Interoperability (VICTORY) initiative addresses these challenges to enable interoperability on Army ground vehicles, as well as facilitate rapid technology insertion and incorporation of new capabilities. VICTORY represents a leap ahead in solving interoperability challenges and defining open standards
Dirner, JasonMelber, AdamPankowski, John A.
ABSTRACT Of the tests of any good theory or suppositional work, the most critical is whether it can forecast the need or accurately describe the number, timing, event and impact of the endeavor. In order to reduce the risk and to exponentially increase the rate of success a continual reevaluation of the data and reconfiguration of the plan will be required, must be properly front-loaded with the appropriate human capital. This is precisely where the application of Six Sigma, Project Management and, Six Sigma for Human Capital works’ intimately with Risk Management to mitigate error and insure the ultimate success of the effort. This is critical in business, critical in the field for greater energy efficiency for soldiers. Unified in concert as core disciplines, the identification of human capital for specialists required at any particular point in the project especially in the definition and design phases, is determined with greater accuracy. Critically predictable and integrated into
Maholick, WilliamGodell, Carl J
In recent years, battery electric vehicles (BEVs) have experienced significant sales growth, marked by advancements in features and market delivery. This evolution intersects with innovative software-defined vehicles, which have transformed automotive supply chains, introducing new BEV brands from both emerging and mature markets. The critical role of software in software-defined battery electric vehicles (SD-BEVs) is pivotal for enhancing user experience and ensuring adherence to rigorous safety, performance, and quality standards. Effective governance and management are crucial, as failures can mar corporate reputations and jeopardize safety-critical systems like advanced driver assistance systems. Product Governance and Management for Software-defined Battery Electric Vehicles addresses the complexities of SD-BEV product governance and management to facilitate safer vehicle deployments. By exploring these challenges, it aims to enhance internal processes and foster cross
Abdul Hamid, Umar Zakir
This document establishes an industry standard checklist for the auditing of the methods and procedures used in aircraft deicing and anti-icing on the ground to support conformance with the industry global standards, AS6285, AS6286 and AS6332. The checklist covers the use of SAE AMS1424 and SAE AMS1428 qualified fluids (Types I, II, III, and IV) and non-fluid methods
G-12T Training and Quality Programs Committee
In order to reduce the pumping loss of low loads and maximize the lean combustion advantage of hydrogen, the paper proposes a load control strategy based on hydrogen mass, called quality control, for improving thermal efficiency and emissions at low loads. The advantages of quality control and the effect of VVT on the combustion performance of hydrogen internal combustion engines under low loads were discussed. The results show that when the relative air–fuel ratio (λ) increases to more than 2.5, the NOx emissions are reduced to less than 3.5 g/kW · h at the brake mean effective pressure (BMEP) below 8 bar, especially when the BMEP is less than 5 bar, the NOx is within 0.2 g/kW · h. Compared to quantity control based on air mass, the quality control strategy based on hydrogen mass achieves over a 2.0% reduction in pumping loss at BMEP levels lower than 4.4 bar. Furthermore, it enhances thermal efficiency by up to 5% at low loads, while maintaining NOx emissions within 0.2 g/kW · h at
Li, YongChen, HongFu, ZhenDu, JiakunWu, Weilong
This document is intended for discrete and integrated digital, wavelength division multiplexing (WDM), and analog/radio frequency (RF) photonic components developed for eventual transition to aerospace platforms. The document provides the reasons for verification of photonic device life test and packaging durability. The document focuses on pre-qualification activity at the optical component level to achieve TRL 6. The recommended tests in this document are intended to excite typical failure mechanisms encountered with photonic devices in an aerospace operating environment, and to build confidence that a technology is qualifiable during a program’s engineering and manufacturing development phase. This recommended practice is targeting components to support electrical-to-optical, optical-to-electrical, or optical-to-optical functionality. Passive optical waveguide, fiber optic cable, and connector components that are integral to a photonic package are included. Component and photonic
AS-3 Fiber Optics and Applied Photonics Committee
This specification covers metric aircraft quality spacers for use as positioners for tubes, flat washers for use as load spreaders, galling protection of adjacent surfaces and or material compatibility, and key or tab washers for use as locks for bolts, nuts, and screws
E-25 General Standards for Aerospace and Propulsion Systems
Vehicle HVAC noise performance is an important vehicle design validation criterion since it significantly links the brand image of a vehicle. It affects the customer’s buying decision and the business of selling vehicles because it directly affects driving comfort. Customers expect continuous improvement in HVAC noise without compromising cooling performance. The process of cascading vehicle-level acoustic performance to subsystem and component levels becomes an important factor in the vehicle NVH development process. It was found that the component-level [HVAC unit without duct] performance of an HVAC system measured in an anechoic chamber was at par when compared to targets, whereas the subsystem-level performance [HVAC unit with duct and dashboard] was on the higher side of the targets. Advanced NVH tools were used to identify the source of noise at the subsystem level. It helped to locate the source and its transfer path. A design modification done at the transfer path location
Titave, Uttam VasantKalsule, ShrikantNaidu, Sudhakara
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
This standard defines the minimum requirements for conducting Measurement Systems Analysis (MSA) for variable and attribute assessment on characteristics as defined on the drawing or specification. It does not define the detailed analytical methods for each type of study as these can be found in existing published texts (see Section 2 for guidance
G-22 Aerospace Engine Supplier Quality (AESQ) Committee
This document establishes age limit and guidance for acceptance of hose and hose assemblies containing elastomeric materials for use in aircraft, space vehicles, missiles and component assemblies thereof at time of delivery to the contractor, procuring activity, or contracting officer. This document does not establish limitations on storage times for military/civil activities nor operating life
G-3, Aerospace Couplings, Fittings, Hose, Tubing Assemblies
This study looks at the effects of low-viscosity fuel on high-pressure fuel pump durability. Several high-pressure fuel pumps were allowed to operate with low-viscosity fuel on a custom test stand until failure. Fuel-pumps lasted 0.3-294 hours before failure. The fuel pumps failed by experiencing a sharp rise in the low-pressure outlet fuel temperature due to scuffing of the camring-bucket interface. We describe a technique for analyzing acoustic emission sensor data to monitor the status of the fuel pump. Acoustic emission signals were able to detect a two-stage failure process of scuffing initiation on a single camring-bucket interface to propagation of damage to the other interfaces
Murthy, NikhilCoburn, VincentMatzke, CalebBerkebile, Stephen
Innovators at NASA Johnson Space Center have developed a method using low-viscosity RTV silicone to form durable seals between polymer bladder and metal bulkhead interfaces to be used for inflatable space habitats
To provide a method by which to assess the cleanliness of new hydraulic fluids. The method is applicable to new mineral and synthetic hydraulic fluids - regardless of packaging. This SAE Standard is not intended as a procedure for operating equipment
CTTC C1, Hydraulic Systems
This SAE Aerospace Recommended Practice (ARP) covers the requirements for the types of glass to be utilized in the fabrication of cover glasses and lighting wedges used in aerospace instruments. It defines the maximum extent of physical defects and recommends standard methods of inspection and evaluation. Definitions of terminology used in this document are covered in 2.2
A-20A Crew Station Lighting
Designing a brake disc is a very challenging job. Besides to being a key item in vehicle safety, we are referring to a product that goes through several manufacturing processes and during its application it is exposed to extreme conditions of mechanical stress, temperature and vibration. The raw material for a large portion of commercial brake discs is normally gray cast iron with the possibility of adding alloy elements. This material is characterized by having high resistance to wear due to friction and having practically zero plasticity. As it is a material without a plastic working regime, it is very important to properly size the product for use, once the material’s resistance limit is reached, a catastrophic failure in operation may be inevitable. Quality control systems in casting and machining have great importance in the development of the disc, but physical tests are always essential in this type of product. Dynamometer tests are great options for validating brake discs, due
Deckmann, Jardel Luisdo Nascimento, Vagner
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