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Viewing 91 to 120 of 1648
2016-04-05
Technical Paper
2016-01-1359
R. Pradeepak, Shyamsundar Kumbhar, Nainishkumar Barhate
Abstract At present, vehicle testing in laboratory is one of the important phase to quicken the product validation process. In the early phase of laboratory testing it is required to evaluate the strength of the vehicle structure through physical rig setup which represents the consumer’s usage. Two and Multiple poster input excitation are among the laboratory rig testing to represent the actual road are used to predict the durability of vehicle components. The road inputs through the poster are known as drive files, a feedback controlled system which reproduces the track or real road recorded specimen’s accelerations, displacements and strains in laboratory. Derivation of drive files in poster testing requires iteration of physical specimen to exactly replicate the actual road.
2016-04-05
Technical Paper
2016-01-0375
Sinan Eroglu, Ipek Duman, Ahmet Hamdi Guzel, Rifat Yilmaz
Abstract The exhaust manifold is one of the engine components which is used to collect the burned gases from the cylinder head and send it to the exhaust hot end aftertreatment system with low engine backpressure. The main purpose of the automotive exhaust manifolds are providing a smooth flow field and must be able to endure thermo-mechanical loadings. The present paper explains the CAE analysis method to assess the design of exhaust manifold of a heavy duty diesel engine. Coupled computational fluid dynamics (CFD) analyses were performed to solve the flow field within the exhaust system and surface convection loading prediction at fluid side and obtain temperature distribution at solid region of exhaust manifold domain. The metal temperature prediction provided by thermal model is used to carry out the durability analysis of the structure.
2016-04-05
Technical Paper
2016-01-1482
Paul Montalbano, Daniel Melcher, Rachel Keller, Thomas Rush, Jay Przybyla
Abstract A number of methods have been presented previously in the literature for determination of the impact speed of a motorcycle or scooter at its point of contact with another, typically larger and heavier, vehicle or object. However, all introduced methods to date have known limitations, especially as there are often significant challenges in gathering the needed data after a collision. Unlike passenger vehicles and commercial vehicles, most motorcycles and scooters carry no onboard electronic data recorders to provide insight into the impact phase of the collision. Recent research into automobile speedometers has shown that certain types of modern stepper motor based speedometers and tachometers can provide useful data for a collision reconstruction analysis if the instrument cluster loses electrical power during the impact, resulting in a “frozen” needle indication.
2016-04-05
Technical Paper
2016-01-1391
Subash Sudalaimuthu, Mohamed Sithik, Roberto Pesce Jr, Chandra Mouli Sankaran
Abstract Based on current trends, there is a huge demand for lightweight components, which improves fuel efficiency and reduces cost of the vehicle. Stiffness based optimization process is simple and straightforward while durability (Misuse load case) based optimizations are relatively complex due to its highly nonlinear behavior. However, durability performances are critical in a front cradle design. So a process needs to be identified for creating a new light weight front cradle design. This study talks about the process of identifying new cast aluminium cradles achieving NVH and durability performance. Load path study using topology optimization is done based on compliance method for the durability load case. A concept model is generated from the topology results. This concept model is further optimized for thickness of ribs and walls by the application of various shape variables. All the critical non linear durability load cases are linked for the shape optimization study.
2016-04-05
Technical Paper
2016-01-0408
Sagar Polisetti, Siddesh Gowda, Nitin Kumar Khanna, Manjul Jyoti
Abstract Suspension system is one of the most important systems in an automobile and the failure in the sub systems or parts would prove catastrophic. A semi-trailing arm (STA) suspension is an independent rear suspension system for automobiles where each wheel hub is located only by a large, roughly triangular arm that pivots at two points onto the chassis or the body. STA usually is subjected to three directional loads viz. vertical, longitudinal and lateral in service. The conventional methodology of validating the system is by applying multi-axial loads or by road load simulation consuming significant amount of time. In this paper an attempt is being made to validate the damper mounting pins by reproducing the damper loads locally instead of validating the entire system. STA was strain gauged at the critical locations and was mounted onto the vehicle.
2016-04-05
Technical Paper
2016-01-0393
Kevin P. Barbash, William V. Mars
Abstract We demonstrate here an accounting of damage accrual under road loads for a filled natural rubber bushing. The accounting is useful to developers who wish to avoid the typical risks in development programs: either the risk of premature failure, or of costly overdesign. The accounting begins with characterization of the elastomer to quantify governing behaviors: stress-strain response, fatigue crack growth rate, crack precursor size, and strain crystallization. Finite Element Analysis is used to construct a nonlinear mapping between loads and strain components within each element. Multiaxial, variable amplitude strain histories are computed from road loads. Damage accrues in this reckoning via the growth of cracks. Crack growth is calculated via integration of a rate law from an initial size to a size marking end-of-life.
2016-04-05
Technical Paper
2016-01-0434
Roshan N. Mahadule, Jaideep Singh Chavan
Abstract Door closing velocity (DCV) is one of the important design parameter for door durability performance. The closing velocity varies with the design parameters and physical properties of the door. The variation in door closing effort may increase or decrease the durability of the door and body components, this can be a concern when the overall vehicle durability performance is considered. This paper gives a mathematical model to calculate the door closing effort accounting the energy sink from various door design parameters such as door seal, latch, hinge, door weight, checkstrap and cabin-pressure. In addition to this, the MS-Excel based computation tool has been developed, which aims to calculate the door closing velocity and energy contribution from each design parameter. This tool is very interactive and effective for durability engineer and helps in improving the quality of vehicle door design.
2016-04-05
Technical Paper
2016-01-1393
Prabhakar Konikineni, V. Sundaram, Kumar Sathish, Sankarasubramanian Thirukkotti
Abstract Fan shroud is one of the critical components in an engine cooling system. It helps in achieving optimum air flow across the heat exchangers. The major challenge is to design a fan shroud which meets noise, vibration and harshness (NVH) requirements without compromising on air flow targets [1]. An improperly designed fan shroud will cause detrimental effects such as undesirable noise and vibration, which will further damage the surrounding components. In current days, multiple simulations and test iterations are carried out in order to optimize its design. The objective of this paper is to provide a design framework to achieve optimized fan shroud that meets NVH requirements in quick turnaround time using Design for Six Sigma (DFSS) approach [2]. The purpose of the Engine cooling system is to maintain the coolant temperature across the vehicle.
2016-04-05
Journal Article
2016-01-1401
Thomas M. Cleary, Timothy Huten, Daniel Strong, Chester S. Walawender
Abstract The use of lightweight materials to produce automotive glazing is being pursued by vehicle manufacturers in an effort to improve fuel economy. As glazing’s become thinner, reduced rigidity means that the critical flaw size needed to create fracture becomes much smaller due to increased strain under load or impact. This paper documents experiments focused on the impact performance of several alternative thin laminate constructions under consideration for windshield applications (including conventional annealed soda-lime glass as well as laminates utilizing chemically strengthened glass), for the purpose of identifying new and unique failure modes that result from thickness reduction. Regulatory impact tests and experiments that focused on functional performance of laminates were conducted. Given the increased sensitivity to flaw size for thin laminates, controlled surface damage was introduced to parts prior to conducting the functional performance tests.
2016-03-27
Technical Paper
2016-01-1736
Manida Tongroon, Amornpoth Suebwong, Mongkon Kananont, Siamnat Panassorn, Paritud Bhandhubanyong
Abstract The effects of high quality biodiesel, namely, partially Hydrogenated Fatty Acid Methyl Ester or H-FAME, on 50,000km on-road durability test of unmodified common-rail vehicle have been investigated. Thailand brand new common-rail light duty vehicle, Isuzu D-Max Extended cab, equipped with 4JK1-TCX engine (DOHC 4-cylinder 2.5L, M/T 4×2, Euro IV emission) was chosen to undergo on-road test composed of well-mixed types of mountain, suburb and urban road conditions over the entire 50,000km. Palm-derived high quality biodiesel, H-FAME, conforming to WWFC (worldwide fuel charter) specification, was blended with normal diesel (Euro IV) at 20% (v/v) as tested fuel. Engine performance (torque and power), emission (CO, NOx, HC+NOx and PM), fuel consumption and dynamic response (0-100km acceleration time and maximum velocity) were analyzed at initial, middle and final distance; whereas, used lube oil analysis was conducted every 10,000km.
2016-02-01
Technical Paper
2016-28-0237
Vinod Verma, V Saravanan, Dinesh Redkar, Arun Mahajan, R Raja, Pankaj Pawar, Ashok Kumar
Abstract A hydraulic power train assembly of an agricultural tractor is meant to lift the heavy implements during field operations and transportation. As it is a crucial member of the tractor for its usage, so the power train assembly needs a properly designed lift arm, rocker arm assembly with better strength and stiffness. There are a standard like IS12224, IS4468 which regulates the test method for hydraulic power and lift capacity of tractor and the layout of hydraulic three point linkage. Computer aided engineering techniques followed by laboratory testing have been deployed in the earlier stages of the product design & development itself to deliver the first time right products to the customer. In this paper, a virtual simulation process has been established to design an agricultural tractor hydraulic lift arm to meet the above requirements. A Design Verification Plan (DVP) has been developed consisting of 3 load cases.
2016-02-01
Technical Paper
2016-28-0168
Prashant Shinde, Omprakash Kota
Abstract Increasing demand of Electric and Hybrid vehicles questions more about Reliability and Lifetime of electronic circuits associated with them. It is very important for a hardware circuit designer to evaluate if module will last the expected lifetime. This paper elaborates the methods and steps to find the expected lifetime of critical components; and to decide whether Hybrid Power Electronics Unit (PEU) will meet the OEM requirements on lifetime. Accelerated thermal stress method is used to determine the required High Temperature Operational Life (HTOL) hours for given thermal profile of Hybrid vehicle passenger car in driving (8,000Hrs), charging(30,000Hrs) and total lifetime (38000Hrs ≈ 15Years). Example calculation of required HTOL hours against expected lifetime for critical component from Hybrid ECUs is explained in this paper. Also inclusions and exclusions of this method in evaluating lifetime assessment are also discussed here.
2015-11-17
Technical Paper
2015-32-0811
Daichi Kano, Nagasaka Kazuya, Go Matsubara, Takumi Kawasaki, Akiyuki Yamasaki, Hiroyuki Kasugai, Hideaki Saito
In the development of a motorcycle frame, the balance between high performance and reliability and a short development period are important. In this study, a fatigue durability evaluation technique for a motorcycle frame was developed to enable highly accurate development within a short period of time. Furthermore, we developed a shaking table excitation system as a means to supplement the road test.
2015-09-29
Technical Paper
2015-01-2722
Sundarram Arunachalam, Ramprabhu Kannan, Nagarajan Gopikannan, Jayaramareddy Sekar
Abstract With advancement of technology, better safety and higher vehicle reliability is primary requirement of end customer especially in public transportation. Hence there exist challenges in design and development of steering system for long haulage and tipper application. In the steering system, track rod is used to steer both the front tyre under different operating condition assisted by power steering system. This paper deals with the failures observed on track rod in long haulage and tipper application with loading conditions. Also the methodology adapted to resolve the field failures.
2015-09-29
Technical Paper
2015-01-2756
Basaran Ozmen, Mehmet Bakir, Murat Siktas, Serter Atamer, Roman Teutsch
Abstract Securing the desired strength and durability characteristics of suspension components is one of the most important topics in the development of commercial vehicles because these components undergo multiaxial variable amplitude loading. Leaf springs are essential for the suspension systems of trucks and they are considered as security relevant components in the product development phase. In order to guide the engineers in the design and testing department, a simulation method is developed as explained by Bakir et al. in a recently published SAE paper [1]. The main aim of the present study is to illustrate the validation of this simulation method for the durability of leaf springs based on the results from testing and measurements. In order to verify this CAE Method, the calculated stresses on the leaf springs are compared with the results of strain gage measurements and the fatigue failures of leaf springs are correlated with the calculated damage values.
2015-09-29
Technical Paper
2015-01-2757
Deepak Anand Subramanian, Nithya Sridhar, N. Obuli Karthikeyan, V. Srinivasa Chandra
Abstract The Indian automotive sector is experiencing a major shift, focusing predominantly towards the levels of quality, reliability and comfort delivered to the customer. Since the entry of global players into the market, there is a rising demand for timely product launches with utmost priority to reliability. In any vehicle, engine isolation systems play a critical role in isolating the engine vibrations from the vehicle chassis. This project details on how testing can aid in reducing the launch time as well as estimating the reliability of the component when used in a different application/vehicle. It proposes a methodology to formulate a life model for the engine mount considering various combinations of predictor parameters affecting its performance over its design life. In order to maintain good correlation with the field (which considers the loading pattern and the environmental factors), warranty data was analyzed and the predictors were chosen appropriately.
2015-09-29
Technical Paper
2015-01-2864
Xinyu Ge, Jarrett Corcoran, Paul Gamble
With stringent emission regulations, many subsystems that abate engine tailpipe-out emissions become a necessary part for engines. The increased level of complexity poses technical challenges for the quality and reliability for modern engines. Among the spectrum of quality control methodologies, one conventional methodology focuses on every component's quality to ensure that the accumulative deviation is within predetermined limits. This conventional methodology tightens the component tolerance during the manufacturing process and typically results in increased cost. Another conventional methodology that is on the other side of the spectrum focuses on tailoring an engine calibration solution to offset the manufacturing differences. Although the tailored engine calibration solution reduces manufacturing cost for components, it increases the development and validation cost for engines.
2015-09-29
Technical Paper
2015-01-2865
Damodar Kulkarni, Pankaj Deore
Abstract Cost-reduction and cost competitiveness have emerged as major strategic tools to an enterprise and are being used all over the world to fight for survival as well as maintain sustainable growth. Maximization of value-creation by enriching the planet, people and the economy should be the key drivers leading to cost-reduction strategies in any business. The main objectives of this paper are to explain the Processes and Principles of Cost-reduction in technology-transfer to low-cost emerging economies to achieve sustainable cost-reduction and create a culture of cost-consciousness throughout an organization.
2015-09-29
Technical Paper
2015-01-2818
Scott Shafer
Abstract All around the world, steps are being taken to improve the quality of our environment. Prominent among these are the definition, implementation, and attainment of increasingly stringent emissions regulations for all types of engines, including off-highway diesels. These rigorous regulations have driven use of technologies like after-treatment, advanced air systems, and advanced fuel systems. Fuel dispensed off-highway is routinely and significantly dirtier than fuel from on-highway outlets. Furthermore, fuels used in developing countries can be up to 30 times dirtier than the average fuels in North America. Poor fuel cleanliness, coupled with the higher pressures and performance demands of modern fuel systems, create life challenges greater than encountered with cleaner fuels. This can result in costly disruption of operations, loss of productivity, and customer dissatisfaction in the off-highway market.
2015-09-29
Technical Paper
2015-01-2816
Andrei Radulescu, Leighton Roberts, Eric Yankovic
Cylinder deactivation (CDA) is an effective method to adjust the engine displacement for maximum output and improve fuel economy by adjusting the number of active cylinders in combustion engines. A Switching Roller Finger Follower (SRFF) is an economic solution for CDA that minimizes changes and preserves the overall width, height, or length of Dual Overhead Cam (DOHC) engines. The CDA SRFF provides the flexibility of either transferring or suppressing the camshaft movement to the valves influencing the engine performance and fuel economy by reducing the pumping losses. This paper addresses the performance and durability of the CDA SRFF system to meet the reliability for gasoline passenger car engines. Extensive tests were conducted to demonstrate the dynamic stability at high engine speeds and the system capacity of switching between high and low engine displacement within one camshaft revolution.
2015-09-29
Journal Article
2015-01-2758
Zhigang Wei, Robert Rebandt, Michael Start, Litang Gao, Jason Hamilton, Limin Luo
In product design and development stage, validation assessment methods that can provide very high reliability and confidence levels are becoming highly demanded. High reliability and confidence can generally be achieved and demonstrated by conducting a large number of tests with the traditional approaches. However, budget constraints, test timing, and many other factors significantly limit test sample sizes. How to achieve high reliability and confidence levels with limited sample sizes is of significant importance in engineering applications. In this paper, such approaches are developed for two fundamental and widely used methods, i.e. the test-to-failure method and the Binomial test method. The concept of RxxCyy (e.g. R90C90 indicates 90% in reliability and 90% in confidence) is used as a criterion to measure the reliability and confidence in both the test-to-failure and the Binomial test methods.
2015-09-27
Technical Paper
2015-01-2666
Scott Lambert
Abstract The Global Brake Safety Council sees an increase in disc brake pads that are prematurely replaced before the end of the friction lining life cycle, due to: 1 Rust related issues such as separation of friction lining from the disc brake shoe2 Fluctuation in critical dimensions. A leading cause for both issues is the use of mill scale steel, or ‘black steel’ (non-pickled and oiled). In the North American aftermarket, as there are little or no steel specifications for disc brake shoes, black steel is increasingly used. GBSC conducted research of discarded disc brake pads from job-shops and engaged in discussions with metallurgists, major pad manufacturers and OE brake foundation engineers to identify root causes of premature pad replacement and the effects of black steel used for disc brake shoe manufacturing. Mill scale is embedded in and around the bond line of the friction lining and the disc brake shoe, causing a weaker bond, susceptible to rust jacking.
2015-09-22
Technical Paper
2015-36-0561
Antonio C. C. Nascimento Filho
Abstract In the design of automotive structural components is common scaling of the data for the "worst case", i.e. a condition of the component of least resistance (stress) and maximum load conditions applied (strength). However, in a real situation, it is not possible to determine with absolute certainty these amounts due to the random nature of the parameters involved. Thus, this design should be treated in a probabilistic manner, where the parameters involved could be considered as random variables, and the project could be qualified for a desired condition of reliability. This paper presents a proposed process (flowchart) for performing computational experiments for reliability analysis in automotive structural components regarding stochastic conditions of involved parameters. The process showed itself as able to identify the most adequate method of predicting reliability to solve problems of stress -strength interference in a design of structural automotive component.
2015-09-22
Technical Paper
2015-36-0553
Alirio Cavalcanti de Brito, Marcelo Lopes de Oliveira e Souza
Abstract The increasing use of embedded electronics in aerospace and automotive vehicles increases the designers' concern regarding the reliability of the components as well as the reliability of their interconnections. The discussion about the most appropriate method for assessing the reliability of solder joints for a given application is an ever-present theme in the literature. Several methods of prediction have been developed for assessing the reliability of solder joints. The standard method established by the industries for assessing reliability of solder joints is the thermal cycling. However, when the thermal distributions in real applications are studied, particularly in some electronic components used in on-board electronics of space systems, the thermal cycling does not represent what actually happens in practice in the packaging.
2015-09-22
Technical Paper
2015-36-0306
Haraldo Rehder, Gustavo P. Rehder
Abstract Durability tests of commercial vehicles are performed on road running uphill and downhill as well as on flat roads; these tests take very long time and have high costs. To lower test time and costs, it is proposed to accelerate the durability tests of commercial vehicles power trains by using a Towing Trailer with an electromagnetic (EM) brake, developed in Brazil, simulating uphill. This Trailer was already presented [1], [2] for cooling test simulation at 20 km/h on commercial vehicles up to 250 HP. In the cabin (cab) of the vehicle under test, there are the braking level control and a laptop, which receives wireless and registers the operational parameters of the Towing Trailer. The GPS in the truck cabin (cab) supply information such as time, speed, latitude and longitude allowing the control of the route.
2015-09-22
Technical Paper
2015-36-0415
I. Coutinho, L. F. Vales, C. B. S. Vimieiro
Abstract Vehicle durability mission loads are an essential and decisive for a reliable life prediction for the component through any durability evaluation. One option to calculate mission loads are multibody models to represent vehicle’s suspension degrees of freedom (dofs) and its dynamic behavior. Generally, trucks have greater wheelbase and then lower natural frequencies than passengers’ vehicles. Therefore are more suitable to dynamic body excitation and the ordinary consideration of a rigid body shell is not relevant. The proposal of this work is to compare the chassis loads considering rigid and flexible frame mounted over the primary suspension. A pseudo-damage was calculated with chassis loads time history for severity assessment. The chose vehicle for the study is an Iveco 4×2 medium range, 6850mm of wheel base, with gross weight of 17ton and leaf springs primary suspension on both: front and rear axles.
2015-09-22
Technical Paper
2015-36-0219
Daniel Haber
Abstract Today, in order to optimize the resources usage and reduce the air pollution, the automobile industry is facing new challenges, with the necessity to improve engines fuel economy, enhance vehicles autonomy and reduce the CO2 emission. One of the solution, which is being much researched, is the car components weight reduction. There is a range of new materials that have been developed to attend the new weight standards. Together with lightweight these materials must also deliver acceptable mechanical properties, easy to manufacture and to assembly capability, good appearance, high durability, good cost-benefit relation and in some cases also acceptable impact energy absorption. This paper presents a review of some of the lightweight materials that are being applied in automobiles, like Carbon Fiber, Aluminum Alloy, Magnesium Alloy, Hybrid Material and Polymer Composites.
2015-09-15
Technical Paper
2015-01-2549
Marc-André Léonard, Jean-François Boland, Christophe Jégo, Claude Thibeault
Abstract Design assurance guidance such as DO-254, and commercial off the shelf (COTS) increasing popularity in high critical mission have pushed the validation and verification methodologies to improve by integrating fault tolerance analysis in reliability assessment. A novel methodology for analysing the sensitivity of digital designs to single event upsets (SEU) is proposed. We first characterize basic combinational circuit models using fault injection via mutation technique at low level of abstraction. Error analysis is performed at primary outputs to identify patterns that are collected in a faulty behaviour library. This library is then used at a high level of abstraction to execute a sensitivity analysis on a digital design model. A reliability report is then generated showing the soft error rate (SER) and the benign errors count. We proved our methodology by analysing the radiation sensitivity of a discrete wavelet transform architecture using two different sets of data.
2015-09-15
Technical Paper
2015-01-2555
Ephraim Suhir, Alain Bensoussan, Johann Nicolics
There is a concern that the continuing trend on miniaturization (Moore's law) in IC design and fabrication might have a negative impact on the device reliability. To understand and to possibly quantify the physics underlying this concern and phenomenon, it is natural to proceed from the experimental bathtub curve (BTC) - reliability “passport” of the device. This curve reflects the combined effect of two major irreversible governing processes: statistics-related mass-production process that results in a decreasing failure rate with time, and reliability-physics-related degradation (aging) process that leads to an increasing failure rate. It is the latter process that is of major concern of a device designer and manufacturer. The statistical process can be evaluated theoretically, using a rather simple predictive model.
2015-09-15
Technical Paper
2015-01-2556
Thomas Rousselin, Guillaume Hubert, Didier Regis, Marc Gatti
Abstract The changes brought by the increasing integration density and the new technological trends have pushed the reliability at its limit. Safety analysis for critical system such as embedded electronics for avionics systems needs to take into account these changes. In this paper, we present the consequences on the deep sub-micron (DSM) CMOS devices concerning their single event effect (SEE) sensitivity. We also propose a new modeling method in order to address these issues.
Viewing 91 to 120 of 1648