Browse Topic: Six Sigma
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
ABSTRACT The key to a better correlation between the interface of systems engineering and project management is in fact a strong sigma relationship. In the recent past this would be termed Value Engineering and was that activity that took place prior to cutting the tools, but it is considerably more common today with the computer systems and software suites in use for modeling and the emphasis on Design for Six Sigma and time to market. All of these tools and methodologies are placing the focus on the final product performance, quality and cost and in so doing helping to again strengthen the manufacturing posture and job outlook of America and re-shore much of the work that was outsourced to save money. Whether of Military or U.S. vehicle manufacturing requirements, for the safety of our programs this work can and should stay in the United States when appropriate. This paper will develop better tools solutions, to provide better risk decisions which improve safety, budget, predictions
In research and development of any automotive industry the main challenge is to virtually simulate probable failures rather than relying on physical testing which consumes time and resources. It is even more challenging when it comes to failure prediction of ABS plastic parts due to its complexity in material, behavior and assembly variations. ABS material is used extensively in automotive vehicles especially in motorcycles and scooters due to its visual and structural benefits at moderate cost. In this paper, the work showcases a methodology to predict failure of ABS parts. In order to do so, understanding the shortcomings in the current system is necessary. With the help of testing database history of various vehicles on proving grounds, root causes and drawback with respect to current simulation process are identified for failure of ABS parts. The input excitations from proving ground are probabilistic, thus, random vibration fatigue process is then introduced to calculate life. By
Ford CEO Jim Farley exposed significant product-development lapses during his company's fourth-quarter-2022 earnings call on February 2. Ford's 4Q profit performance was no-excuses dismal. Its causes, he stated, run deep. So, in front of investors and media, Farley boldly lifted Ford's PD skirt to reveal alarming management and process issues behind the dysfunction. The fire had to be lit. “We didn't know that our wiring harness for Mach-E was 1.6 kilometers longer than it needed to be,” Farley stated on the call. “We didn't know it's 70 pounds heavier and that that's [worth] $300 a battery. We didn't know that we underinvested in braking technology to save on the battery size.” Credit to CNN's Chris Isidore for roping these EV-specific details into a Feb. 3 story
Climate change and global warming are the main threats to our planet. CO2 emissions contribute vastly to climate change and automobiles contribute to CO2 emissions. We can reduce the CO2 emissions from vehicles by various measures, out of which shredding weight is one of the solutions, and even for hybrid or electric vehicles there will be a need for weight reduction for the control of global CO2 emission. We can shred the weight of the automobiles by replacing the components with lighter materials or by optimizing the components by removing excessive material. It is not always possible to change the materials due to its mechanical, thermal properties, manufacturability etc. This leads to the other method which is removing excessive material. Today, we use different simulation tools like ANSYS for topology or shape optimization. During the traditional optimization, we perform the simulation, based on the available design limits and propose the best optimized design to the customer
The Bharat Stage VI emission norms in India is driving the use of more complex after treatment systems for diesel engines, to meet the stringent emission limits. The after-treatment system typically includes theSelective Catalytic Reduction (SCR) catalyst and the Diesel Oxidation Catalyst (DOC) - Diesel Particulate Filter (DPF) systems to reduce engine out emissions of Nitrogen Oxides (NOx), hydrocarbons (HC), and particulates respectively. For a durable functioning of the aftertreatment system, cleaning of these components at regular intervals is required, the process termed as ‘regeneration’. The most common industry technique for regeneration is to use the existing injectors in the engine, to dose the extra fuel which is burnt in the DOC for regeneration. This has been a cost effective and simpler technique compared to the external hydrocarbon dosing system. But the tradeoff involved with this in-cylinder dosing technique is the risk of fuel in oil (FIO). The extra fuel injected
Aerostructures assembly (ASA) is a vital process in any aircraft production phase that integrates individual detail parts, sub-assemblies, major assemblies, components, and systems into a final deliverable, a completed aircraft structure fit for flight. ASA in an aircraft’s entire product life cycle represents more than half the cost and time that is a significant portion of the total aircraft production cost. ASA depends on highly skilled manual labor work across the global aerospace supply chain for various assembly processes and subprocesses required for assembling detail parts into sub-assemblies and components to achieve the design intent of the load-carrying aerostructure that is airworthy for the complete operational cycle till disposal of an aircraft. The assembly processes can significantly impact quality, safety, and reliability and can affect an aircraft structure’s performance and design intent. To mitigate the increase in defects due to non-standardization and to fulfill
Roof is one of the major subsystems of the Body-In-White Structure, which significantly affects the vehicle strength and durability performance criteria. The roof structure should meet the functional targets under the standard operating conditions. Roof design considering various parameters in the initial phase is beneficial in reducing the product timeline for the OEM. The first-time right approach provides an opportunity for Optimization and Cost benefits in the longer term. This paper provides the use of Design for Six Sigma techniques to arrive at a robust and optimum design for the standard roof structure. The roof structure is designed to meet the operating conditions for durability. Roof finite element models are developed with control factors that affect the structure design. Virtual Analysis is performed on the Standard roof structure models. Roof Performance is the contribution of multiple factors such as roof material, thickness, number of roof bows, positioning of the bows
Design for Six Sigma (DFSS) is an essential tool and methodology for innovation projects to improve the product design/process and performance. This paper aims to present an application of the DFSS Taguchi Method for an automotive/vehicle component. High-Pressure Vacuum Assist Die Casting (HPVADC) technology is used to make Cast Aluminum Front Shock Tower. During the vehicle life, Shock Tower transfers the road high impact loads from the shock absorber to the body structure. Proving Ground (PG) and washout loads are often used to assess part strength, durability life and robustness. The initial design was not meeting the strength requirement for abusive washout loads. The project identified eight parameters (control factors) to study and to optimize the initial design. Simulation results confirmed that all eight selected control factors affect the part design and could be used to improve the Shock Tower's strength and performance. Non-dynamic analysis Smaller-the-Better (STB) was used
Vehicle suspension parts are subjected to variable road loads, manufacturing process variation and high installation loads in assembly process. Seam welding can be considered as such process to connect more components and parts. Typical in a Mc Pherson suspension system stabilizer bar link is connected to the strut assembly through ball stud and clamped to a bracket welded to the outer strut tube. Cracks have been observed in the stabilizer bar link bracket welds of vehicles in the field, effecting the functionality of the suspension system. During preliminary phase of product development CAE assessment of the seam weld is carried out against road load data, if the design does not meet the targets enabler studies are carried out in an iterative approach. Various design variables (control factors) can be considered to carry out the iterations. Design for Six Sigma (DFSS) and Taguchi approach are used to carry out a parametric design study of the weld attachment to quantify the effect of
The aerospace industry had recently initiated the journey towards the transition to the Advanced Product Quality Planning (APQP) process, for the manufacturing and assembly process of their products in their supply chain, aiming to continually meet the rising delivery demand of the global aerospace industry and improve the quality and costs of current products and services. Of the various APQP process elements and requirements, one specific requirement is the application of Design For Manufacturing and Assembly (DFMA®) guidelines, early in the product design and development phase, aiming to design, develop, and analyze the designs for effective and efficient product realization. These guidelines, though widely used, are fairly new for the aerospace industry, and there is no standard framework readily available to aerospace organizations for the successful deployment of these guidelines in the Aerospace APQP process. The study in this technical paper is a continuation of the research
The main components present in the clutch disc assembly are friction facing, metallic disc, damper spring, drive plate, retainer plate, washers and hub. Among the parts, metallic disc is the weakest component present in the clutch system and moreover it is subjected to higher fatigue load during the vehicle operating condition. Hence it is necessary to make the design as more robust to withstand the worst loading conditions. The metallic disc is subjected to axial load, torque, speed and axial misalignment during vehicle operating condition. Through bench test, it was observed that higher severity in metallic disc was due to axial misalignment. Initially, metallic disc was tested for axial misalignment condition up to failure through bench test and the number of cycles were determined. Structural simulation was simulated as the same as bench test using ANSYS workbench 19.2. From this better correlation arrived between FEA and bench test. To make FEA result more robust, tolerance study
Since the electronic shift lever detent system is used in vehicles on a large scale, it is urgent to solve the problem of robustness parameter design of the shift quality of SLDS under the uncertain dynamic parameters and manufacturing tolerances. We Build the MBD model of shift lever detent system, selecte the evaluation indicator for shifting quality and propose a two-stage method which associates the deterministic optimization of grey relational grade with the robustness parameter optimization of six sigma, in the early stage of product quality design. We use the grey relational grade to take the place of SNR in deterministic optimization, and compute the the optimal combination of controllable factors and their levels. The controllable parameters of shift lever detent system include three parameters that determine the detent profile structure parameters, spring parameters and contact pair parameters. The deterministic optimization of grey relational grade provides initial values
Active grille shutter (AGS) in a vehicle provides aerodynamic benefit at high vehicle speed by closing the front-end grille opening. At the same time this causes lesser air flow through the cooling module which includes the condenser. This results in higher refrigerant pressure at the compressor outlet. Higher head pressure causes the compressor to work more, thereby possibly negating the aerodynamic benefits towards vehicle power consumption. This paper uses a numerical method to quantify the compressor power consumed in different scenarios and assesses the impact of AGS closure on total vehicle energy consumption. The goal is to analyze the trade-off between the aerodynamic performance and the compressor power consumption at high vehicle speeds and mid-ambient conditions. These so called real world conditions represent highway driving at mid-ambient temperatures where the air-conditioning (AC) load is not heavy. AC system is modeled using 1D methodology and its performance simulated
Nowadays development of automotive HVAC is a challenging task wherein thermal comfort and safety are very critical factors to be met. HVAC system is responsible for the demisting and defrosting of the vehicle’s windshield and for creating/maintaining a pleasing environment inside the cabin by controlling airflow, velocity, temperature and purity of air. Fog or ice which forms on the windshield is the main reason for invisibility and leads to major safety issues to the customers while driving. It has been shown that proper clear visibility for the windshield could be obtained with a better flow pattern and uniform flow distribution in the defrost mode of the HVAC system and defrost duct. Defroster performance has received significant attention from OEMs to meet the specific global performance standards of FMVSS103 and SAE J902. Therefore, defroster performance is seriously taken into consideration during the design of HVAC system and defroster duct. The HVAC unit provides hot air to the
It is a challenging task to find an optimal design concept for a truck frame structure given the complexity of loading conditions, vehicle configurations, packaging and other requirements. In addition, there is a great emphasis on light weight frame design to meet stringent emission standards. This paper provides a framework for fast and efficient development of a frame structure through various design phases, keeping durability in perspective while utilizing various weight reduction techniques. In this approach frame weight and stiffness are optimized to meet strength and durability performance requirements. Fast evaluation of different frame configurations during the concept phase (I) was made possible by using DFSS (Design for Six Sigma) based system synthesis techniques. This resulted in a very efficient frame ladder concept selection process. Frame gauge optimization during the subsequent development phase (II) utilizing a newly developed damage based approach greatly reduced the
Robust engineering is an integral part of the quality initiative, Design For Six Sigma (DFSS), in most companies to enable good designs and products for reliability and durability. Taguchi’s signal-to-noise ratio has been considered as a good performance index for robustness for many years. An alternate approach that is direct and simple for measuring robustness is proposed. In this approach, robustness is measured in terms of an augmented output response and it is a composite index of variation and efficiency of a system. This formulation represents an engineering design intent of a product in a statistical sense, so engineers can understand, communicate, and resonate at ease. Robust formulations are illustrated and discussed with case studies for smaller-the-better, nominal-the-best, and dynamic responses. Confirmation runs of optimization show good agreement of the augmented response with the additive predictive models
In this paper we present an integrated approach which combines analysis of the effect of simultaneous variations in model input parameters on component or system temperatures. The sensitivity analysis can be conducted by varying model input parameters using specific values that may be of interest to the user. The alternative approach is to use a structured set of parameters generated in the form of a DFSS DOE matrix. The matrix represents a combination of simulation conditions which combine the control factors (CF) and noise factors. CF’s are the design parameters that the engineer can modify to achieve a robust design. Noise factors include parameters that are outside the control of the design engineer. In automotive thermal management, noise factors include changes in ambient temperature, exhaust gas temperatures or aging of exhaust system or heat shields for example. The integrated approach, presented in this paper, provides powerful tools that can significantly reduce the total
An Aircraft’s assembly process plays a vital part in its design, development and production phases and contributes to about half of the Total cost spent in its entire product lifecycle. Design For Assembly (DFA®) principles have been one of the proven effective methodologies in Automotive and Process industries. Use of DFA® principles have resulted in proactively simplifying and optimizing engineering designs with reduced product costs, and improved efficiencies in product design and performance. Standardization of Assembly guidelines is vital for “Design and Build” and “Build-To-Print” manufacturing supplier organizations. However, Standardizing design methodologies, through use of proven tools like Advanced Product Quality Planning, (APQP) are still in the initial stages in Aerospace part and process design processes. Thus, there is a tremendous opportunity for research on the application of the existing DFA® guidelines to optimize Engineering Aerospace Assembly processes aiming to
Multi-layered, high-density polyethylene (HDPE) fuel tanks are increasingly being used in automobiles due to advantages such as shape flexibility, low weight and corrosion resistance. Though, HDPE fuel tanks are perceived to be safer as compared to metallic tanks, the material properties are influenced by service temperature. At higher temperatures (more than 80oC), plastic fuel tanks can soften, sag and eventually spill out the fuel, while the extreme cold (less than -20°C) can lead to potential cracking problems. Damage may also occur due to accidental drop while handling or due to an impact from a flying shrapnel. This can be catastrophic due to flammability of the fuel. The objective of this work is to characterize and develop a failure model for the plastic fuel tank material to simulate damage and enhance predictive capability of CAE for chassis and safety load cases. Different factors influencing the material properties such as service temperature, rate of deformation, state of
Drive cycles have been an integral part of emission tests and virtual simulations for decades. A drive cycle is a representation of running behavior of a typical vehicle, involving the drive pattern, road characteristics and traffic characteristics. Drive cycles are typically used to assess vehicle performance parameters, perform system sizing and perform accelerated testing on a test bed or a virtual test environment, hence reducing the expenses on road tests. This study is an attempt to design a relatively robust process to generate a real world drive cycle. It is based on a Six Sigma design approach which utilizes data acquired from real world road trials. It explicitly describes the process of generating a drive cycle which closely represents the real world road drive scenario. The study also focuses on validation of the process by simulation and statistical analysis
The automotive Air Induction System (AIS) is an important part of the engine systems which delivers the air to the engine. A well-designed AIS should have low flow restriction and radiates a good quality sound at the snorkel. The GT-Power simulation tool has been widely utilized to evaluate the snorkel noise in industry. In Fiat Chrysler Automobiles, the simulation method enhanced with Design For Six Sigma (DFSS) approach has been developed and implemented in AIS development to meet the functional requirements. The development work included different types of DFSS projects such as identifying new concept, robust optimization and robust assessment etc. In this paper, the work of a robust optimization project is presented on developing an AIS parametric model to achieve optimized snorkel noise performance for a V8 engine. First, the theory of AIS acoustic modeling using GT-power and DFSS robust optimization using Taguchi’s parameter design method are described. Secondly, the effects of
Motivation - Ambiguous product targets, a global market, innovation pressure, changing process requirements and limited resources describe the situation for engineering management in the most R&D organizations. Achieving complex objective with limited resources is a question of performance. Performance in engineering departments is highly correlated to the existing capability of the engineering staff. When the reduction of engineering effort in development projects becomes additional goal for the management, an increase of engineering productivity is required. International engineering sites are established globally to push the capacity limits and to increase the productivity by the accessing big employment markets of engineering talents. By solving the conflict of limited resources and complex engineering goals, a need organizational challenge occurs - global co-engineering. Co-engineering is the extension of simultaneous engineering by the distribution of tasks and responsibilities
Recently, upon customer’s needs for noise-free brake, carmakers are increasingly widely installing damping kits in their braking systems. However, an installation of the damping kits may excessively increase softness in the brake system, by loosening stroke feeling of a brake pedal and increasing compressibility after durability. To find a solution to alleviate this problem, we first conducted experiments to measure compressibility of shims by varying parameters such as adhesive shims (e.g., bonding spec., steel and rubber thickness), piston’s shapes (e.g., different contact areas to the shims), and the numbers of durability. Next, we installed a brake feeling measurement system extended from a brake pedal to caliper. We then compared experimental parameters with brake feeling in a vehicle. Finally, we obtained an optimized level of brake feeling by utilizing the Design for Six Sigma (DFSS). Our results may provide practitioners with a better guideline by helping them design a brake
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