Criteria

Display:

Results

Viewing 31 to 60 of 10325
2017-03-28
Journal Article
2017-01-0325
Samer Abbas, John Joyce
Abstract Severity-mitigating mechanisms (typically software-based) detect failures in a system and perform functions in order to reduce the severities of failures. Various approaches to FMEA analysis of severity-mitigating mechanisms exist within the industry. Three are compared and contrasted. Each method is compared against its ability to capture the three fundamental failures of a system that has severity-mitigating mechanisms: 1 a failure occurs and mitigating action is taken,2 a failure occurs and mitigating action is not taken,3 no failure occurs but mitigating action is taken. One method is advocated over the others because it: uses existing FMEA formatting; addresses all three cases; supports consistent linkage between FMEAs in a hierarchy of systems with any number of layers.
2017-03-28
Technical Paper
2017-01-0326
Samuel J. Tomlinson, Martin J D Fisher, Thomas Smith, Kevin Pascal
Abstract When sealing an application with a radial O-ring system design there is a balance that must be struck between O-ring function and the ease of assembly. If design parameters are not properly controlled or considered it is possible to design an O-ring seal that would require assembly insertion forces that exceed acceptable ergonomic practices from a manufacturing standpoint. If designs are released into production with these high insertion forces manufacturing operators will struggle to assemble parts, creating opportunity for potential operator injury due to repetitive strain or CTD. In this study several variables impacting O-ring system insertion forces were tested to quantify the effects. Results were analyzed to identify design controls that could be implemented from an early design phase to optimize both functionality and ease of assembly.
2017-03-28
Journal Article
2017-01-0404
Anatoliy Dubrovskiy, Sergei Aliukov, Sergei Dubrovskiy, Alexander Alyukov
Abstract Currently, a group of scientists consisting of six doctors of technical sciences, professors of South Ural State University (Chelyabinsk, Russia) has completed a cycle of scientific research for creation of adaptive suspensions of vehicles. We have developed design solutions of the suspensions. These solutions allow us to adjust the performance of the suspensions directly during movement of a vehicle, depending on road conditions - either in automatic mode or in manual mode. We have developed, researched, designed, manufactured, and tested experimentally the following main components of the adaptive suspensions of vehicles: 1) blocked adaptive dampers and 2) elastic elements with nonlinear characteristic and with improved performance.
2017-03-28
Technical Paper
2017-01-0005
Yun Liu, Sung-Kwon Hong, Tony Ge
Abstract Powertrain drivability evaluation and calibration is an important part of vehicle development to enhance the customer experience. This step mainly takes place on vehicle testing very late in the product development cycle, and is associated with a considerable amount of prototype, test facility, human resource and time cost. Design change options at this stage are also very limited. To reduce the development cost, a model based computer aided engineering (CAE) method is introduced and combined with hardware-in-the-loop (HIL) simulation technology. The HIL simulation method offers a possibility for drivability prediction and development in early phase of product cycle. This article describes the drivability HIL simulation process under development in Ford. The process consists of real time capable multi-domain CAE model integration, powertrain control module (PCM) and HIL simulator interface development and drivability HIL simulation.
2017-03-28
Technical Paper
2017-01-0022
Holger Zeltwanger
Abstract In-vehicle networks (IVN) have been standardized from the beginning. The story of IVN standardization started at the beginning of the 90s. Today, several IVN technologies have been internationally standardized by ISO (International Organization for Standardization) including the related conformance test plans. But as all electronic technologies, IVNs are a matter of improvement and change due to new requirements and gained experiences. This makes it difficult to always keep the standard backwards compatible, in particular if immature approaches are submitted. Furthermore, new communication protocols are knocking on the door of international standardization bodies. The automotive industry itself is conservative and adapts new IVNs slowly. There are also concerns regarding too many different bus systems and networks in one vehicle. This paper discusses the benefits and challenges of the standardization of IVNs.
2017-03-28
Technical Paper
2017-01-0023
Naoya Tsuchiya, Tomohisa Kishigami, Eiichirou Kawakami
Abstract In-vehicle network communication is evolving faster speeds and higher performance capabilities, connecting the information possessed by ECU and sensors with the in-vehicle electronic systems which are continuing to develop. With the evolution of the complicated networks, it is becoming difficult to develop them without many verification of actual machine. On the other hand, as for the verification means required at the logic level or physical level for a network verification through ECU design, virtual verification in the whole vehicle is difficult due to speed increases and the sheer size of the system. Therefore, it is only applicable for systems which are limited to a domain or an area, and flexible and timely utilization would be difficult due to the changes in specifications.
2017-03-28
Technical Paper
2017-01-0201
Tejas Janardan Sarang, Amar Phatak, Jay Bendkhale
Abstract In the recent years, the timeline of releasing a new vehicle has decreased drastically due to rapidly changing trends in the automotive industry. Therefore, it is very important to constantly optimize the development phases, starting from concept initiation to the final testing of production ready vehicle. The real world tests conducted on vehicles take huge amount of time, since these tests are carried out for large kilometers to periodically analyze tire wear, clutch wear and brake failure. Collecting large kilometers of CAN data is also tedious and time consuming due to various unwanted variables which add up during real world tests. In this paper, a technique known as Rescaled Range Analysis is adapted to abridge the collection of kilometers data from testing by nearly ten times. This analysis estimates a Hurst coefficient to correlate the entire data with its divided parts. The division factor of the entire data is very crucial for the analysis.
2017-03-28
Technical Paper
2017-01-0200
Hongwei Zhang, Liangjin Gui, Zijie Fan
Abstract Road test simulation on test rig is widely used in the automobile industry to shorten the development circles. However, there is still room for further improving the time cost of current road simulation test. This paper described a new method considering both the damage error and the runtime of the test on a multi-axial test rig. First, the fatigue editing technique is applied to cut the small load in road data to reduce the runtime initially. The edited road load data could be reproduced on a multi-axial test rig successfully. Second, the rainflow matrices of strains on different proving ground roads are established and transformed into damage matrices based on the S-N curve and Miner rules using a reduction method. A standard simulation test for vehicle reliability procedure is established according to the proving ground schedule as a target to be accelerated.
2017-03-28
Technical Paper
2017-01-0199
Harpreet Grewal, Anthony D'Amato, Kathleen Rossie
Abstract Designing a durability test for an automatic transmission that appropriately reflects customer usage during the lifetime of the vehicle is a formidable task; while the transmission and its components must survive severe usage, overdesigning components leads to unnecessary weight, increased fuel consumption and increased emissions. Damage to transmission components is a function of many parameters including customer driving habits and vehicle and transmission characteristics such as weight, powertrain calibration, and gear ratios. Additionally, in some cases durability tests are required to verify only a subset of the total parameter space, for example, verifying only component modifications. Lastly, the ideal durability test is designed to impose the worst case loading conditions for the maximum number of internal components, be as short as practicable to reduce testing time, with minimal variability between tests in order to optimize test equipment and personnel resources.
2017-03-28
Technical Paper
2017-01-0198
Jiliang Zhang, Carolyn Wozniak
Component failures in electrical vehicle (EV) charge stations may lead to a complete loss or reduction of charging power available to the vehicles. The multistate coherent structure is employed to model the system reliability and availability of the charging cabinet and station. The number of vehicles and the customer behavior in choosing charge port is considered in the analysis. The methodology is illustrated with a simplified charging cabinet example. The usefulness of the methodology presented in this paper to EV charge station design and service is further discussed. In summary, the framework of a multistate system reliability modeling is developed for EV charge station, which can be used for further studies. The authors believe it can find many engineering applications in EV charge station and beyond.
2017-03-28
Journal Article
2017-01-0204
Gaurav Gosain, Billy Holland, Thomas McKinley
Abstract Understanding customer usage space and its impact on engine, after treatment, and vehicle duty cycles poses challenges in terms of data noise, data variability and complex interrelations. Moreover, humans are only able to concurrently visualize at most 2 to 3 dimensions, limiting the number of engine parameters that can be considered. Previous studies in this field have been limited to understanding trends in data based on single duty cycle, comparatively short application period and time domain segmented clustering analysis. These techniques have been used to determine representative cycles for specific applications. In this paper, K-Means Clustering is used to classify customer usage space based on tens of dimensions, for multiple duty cycles, and over years of operation. The clusters are evaluated based on system, sub-system, and component-based metrics on a day based unsegmented engine parameter values.
2017-03-28
Technical Paper
2017-01-0202
Zhigang Wei, Raghuram Mandapati, Ranjith Nayaki, Jason Hamilton
Life testing or test-to-failure method and binomial testing method are the two most commonly used methods in product validation and reliability demonstration. The two-parameter Weibull distribution function is often used in the life testing and almost exclusively used in the extended time testing, which can be considered as an accelerated testing method by appropriately extending the testing time but with significantly reduced testing samples. However, the fatigue data from a wide variety of sources indicate that the three-parameter Weibull distribution function with a threshold parameter at the left tail is more appropriate for fatigue life data with large sample sizes. The uncertainties introduced from the assumptions about the underlying probabilistic distribution would significantly affect the interpretation of the test data and the assessment of the performance of the accelerated binomial testing methods, therefore, the selection of a probabilistic model is critically important.
2017-03-28
Journal Article
2017-01-0197
Vasiliki Tsianika, Vasileios Geroulas, Zissimos Mourelatos, Igor Baseski
Abstract Fatigue life estimation, reliability and durability are important in acquisition, maintenance and operation of vehicle systems. Fatigue life is random because of the stochastic load, the inherent variability of material properties, and the uncertainty in the definition of the S-N curve. The commonly used fatigue life estimation methods calculate the mean (not the distribution) of fatigue life under Gaussian loads using the potentially restrictive narrow-band assumption. In this paper, a general methodology is presented to calculate the statistics of fatigue life for a linear vibratory system under stationary, non-Gaussian loads considering the effects of skewness and kurtosis. The input loads are first characterized using their first four moments (mean, standard deviation, skewness and kurtosis) and a correlation structure equivalent to a given Power Spectral Density (PSD).
2017-03-28
Technical Paper
2017-01-1678
Joseph Antony John Selvaraj, Sivapalan Balanayagam
Modern Instrument Panel Clusters (IPC) are equipped with thin film transistor (TFT) based displays. Contrary to conventional IPCs with hard gauges and liquid crystal diode (LCD) displays, TFT displays offer versatile usage of display area with soft gauges, reconfigurable menus, tell tales, graphics and warning messages etc., At the same time, the number of possible screen combinations, multicolor images validation and different screen arbitration become significantly complex. Thereby display validation turns out to be a complex and time consuming task in IPC validation. The task becomes even more complex when change requests are to be incorporated during final phases of development stage. This paper provides a novel solution that helps to validate any graphical and behavioral changes with minimum effort and maximum accuracy.
2017-03-28
Technical Paper
2017-01-1674
Wenxu NIU, Ke Song, Tong Zhang
Abstract X-in-the-loop (XiL) framework is a validation concept for vehicle product development, which integrates different virtual and physical components to improve the development efficiency. In order to develop and validate an extended validation method based on XiL, Tongji University in Shanghai, China and the Karlsruhe Institute of Technology (KIT) in Karlsruhe, Germany co- performed a feasibility study about an X-in-the-distance-loop demonstration platform. The X-in-the-distance-loop demonstration platform includes a MATLAB/Simulink software platform and geographically distributed equipment (driver simulator, driving electric motor and dynamometer test stand), which are used to conduct bidirectional experiments to test communication of powertrain data between China and Germany.
2017-03-28
Technical Paper
2017-01-1671
Johannes Bach, Marc Holzäpfel, Stefan Otten, Eric Sax
Abstract Enhanced technological capabilities render the application of various, increasingly complex, functional concepts for automated driving possible. In the process, the significance of automotive software for a satisfactory driving experience is growing. To benefit from these new opportunities, thorough assessment in early development stages is highly important. It enables manufacturers to focus resources on the most promising concepts. For early assessment, a common approach is to set up vehicles with additional prototyping hardware and perform real world testing. While this approach is essential to assess the look-and-feel of newly developed concepts, its drawbacks are reduced reproducibility and high expenses to achieve a sufficient and balanced sample. To overcome these drawbacks, new flexible, realistic and preferably automated virtual test methods to complement real world verification and validation are especially required during early development phases.
2017-03-28
Journal Article
2017-01-1669
Keiichiro Numakura, Kenta Emori, Akinori Okubo, Taku Shimomura, Tetsuya Hayashi
Abstract This paper presents the technologies incorporated in an electric vehicle (EV)/hybrid electric vehicle (HEV) inverter built with power semiconductors of silicon carbide (SiC) metal-oxide-semiconductor field-effect transistors (MOSFETs) instead of conventional silicon (Si) insulated gate bipolar transistors (IGBTs). A SiC inverter prototype of 2.9 L in size for driving an 80-kW motor was fabricated and evaluated on a motor test bench. The SiC inverter prototype attained average efficiency of 98.5% in the Worldwide harmonized Light-duty Test Cycle (WLTC) driving mode. The two main technologies achieved with this SiC inverter prototype are described. The first one is a new direct-cooled power module with a thick copper (Cu) heat spreader located under the semiconductors that improves thermal resistance by 34% compared with a conventional direct-cooled power module.
2017-03-28
Technical Paper
2017-01-0835
Hitoshi Shibata, Takeshi Mizobuchi, Makoto Iwamuro, Akinori Koda, Hidekazu Omura
Abstract Gasoline direct injection (GDI) systems are a main development focus for global environment issues and energy security. At the same time, it is also important to challenge further development of Multi point injection (MPI) systems for a simple and robust combustion system responding to global fuels ,required for the growing automotive markets in emerging countries, especially in the A, B vehicle segments. This paper focuses on reducing wall wetting in cold conditions and maximizing mixture cooling by fuel vaporization (preventing knocking) in high load conditions as key development points of MPI systems. We propose a dual MPI system enhancing direct flow of spray into the combustion chamber to gain part of the benefit of GDI in addition to the homogeneity advantage of an MPI system. This dual MPI system requires finer atomization with at the same time robustness against intake airflow.
2017-03-28
Technical Paper
2017-01-0064
Agish George, Jody Nelson
Abstract The ISO 26262 standard for functional safety was first released in 2011 and has been widely incorporated by most OEMs and Tier1 suppliers. The design and conformance of the product to functional safety standards is strongly intertwined with the product development cycle and needs to be carefully managed. The consideration for functional safety needs to begin right from the product’s concept phase through engineering and production and finally decommissioning. The application of the standard in a project can bring significant challenges especially to managers who are relatively new to the standard. This paper provides some guidelines on the key tasks involved in managing ISO26262 in projects and some ways to approach them. The paper is expected to help managers manage ISO26262 compliant projects. The paper also tries to come up with a metric that can be used for resource estimation for implementing ISO26262 in projects.
2017-03-28
Technical Paper
2017-01-0173
Stephen Andersen, Sourav Chowdhury, Timothy Craig, Sangeet Kapoor, Jagvendra Meena, Prasanna Nagarhalli, Melinda Soffer, Lindsey Leitzel, James Baker
Abstract This paper quantifies and compares the cooling performance and refrigerant and fuel cost savings to automobile manufacturers and owners of secondary-loop mobile air conditioners (SL-MACs) using refrigerants hydrofluorocarbon (HFC)-134a and the available alternatives HFC-152a and HFO-1234yf. HFC-152a and HFO-1234yf are approved for use by the United States Environmental Protection Agency (US EPA) and satisfy the requirements of the European Union (EU) F-Gas Regulations. HFC-152a is inherently more energy efficient than HFC-134a and HFO-1234yf and in SL-MAC systems can generate cooling during deceleration, prolong comfort during idle stop (stop/start), and allow powered cooling at times when the engine can supply additional power with the lowest incremental fuel use. SL-MAC systems can also reduce the refrigerant charge, emissions, and service costs of HFO-1234yf.
2017-03-28
Journal Article
2017-01-0622
Sury Janarthanam, Sarav Paramasivam, Patrick Maguire, James Gebbie, Douglas Hughes
Abstract Hybrid Electric Vehicles (HEV) utilize a High Voltage (HV) battery pack to improve fuel economy by maximizing the capture of vehicle kinetic energy for reuse. Consequently, these HV battery packs experience frequent and rapid charge-discharge cycles. The heat generated during these cycles must be managed effectively to maintain battery cell performance and cell life. The HV battery pack cooling system must keep the HV battery pack temperature below a design target value and maintain a uniform temperature across all of the cells in the HV battery pack. Herein, the authors discuss some of the design points of the air cooled HV battery packs in Ford Motor Company’s current model C-Max and Fusion HEVs. In these vehicles, the flow of battery cooling air was required to not only provide effective cooling of the battery cells, but to simultaneously cool a direct current high voltage to low voltage (DC-DC) converter module.
2017-03-28
Technical Paper
2017-01-0632
Chen Yang, Haiyuan Cheng, Zizhu fan, Jiandong Yin, Yuan Shen
Abstract In recent years, more attention has been focused on environment pollution and energy source issues. As a result, increasingly stringent fuel consumption and emission legislations have been implemented all over the world. For automakers, enhancing engine’s efficiency as a must contributes to lower vehicle fuel consumption. To reach this goal, Geely auto started the development of a 3-cylinder 1.0L turbocharged direct injection (TGDI) gasoline engine to achieve a challenging fuel economy target while maintaining fun-to-drive and NVH performance. Demanding development targets for performance (specific torque 205Nm/L and specific power 100kW/L) and excellent part-load BSFC were defined, which lead to a major challenge for the design of engine systems, especially for combustion system.
2017-03-28
Journal Article
2017-01-0642
Richard Osborne, Trevor Downes, Simon O'Brien, Ken Pendlebury, Mark Christie
Abstract The Magma engine concept is characterised by a high compression ratio, central injector combustion system employed in a downsized direct-injection gasoline engine. An advanced boosting system and Miller cycle intake-valve closing strategies are used to control combustion knock while maintaining specific performance. A key feature of the Magma concept is the use of high CR without compromise to mainstream full-load performance levels. This paper focuses on development of the Magma combustion system using a single-cylinder engine, including valve event, air motion and injection strategies. Key findings are that Early Intake Valve Closing (EIVC) is effective both in mitigating knock and improving fuel consumption. A Net Indicated Mean Effective Pressure (NIMEP) equivalent to 23.6 bar Brake Mean Effective Pressure (BMEP) on a multi-cylinder engine has been achieved with a geometric compression ratio of 13:1.
2017-03-28
Technical Paper
2017-01-1174
Vincent Freyermuth, Aymeric Rousseau
Today’s value proposition of plug-in hybrid electric vehicles (PHEV) and battery electric vehicles (BEV) remain expensive. While the cost of lithium batteries has significantly decreased over the past few years, more improvement is necessary for PHEV and BEV to penetrate the mass market. However, the technology and cost improvements of the primary components used in electrified vehicles such as batteries, electric machines and power electronics have far exceeded the improvements in the main components used in conventional vehicles and this trend is expected to continue for the foreseeable future. Today’s weight and cost structures of electrified vehicles differ substantially from that of conventional vehicles but that difference will shrink over time. This paper highlights how the weight and cost structures, both in absolute terms and in terms of split between glider and powertrain, converge over time.
2017-03-28
Journal Article
2017-01-1154
Jimmy Kapadia, Daniel Kok, Mark Jennings, Ming Kuang, Brandon Masterson, Richard Isaacs, Alan Dona, Chuck Wagner, Thomas Gee
Abstract The automotive industry is rapidly expanding its Hybrid, Plug-in Hybrid and Battery Electric Vehicle product offerings in response to meet customer wants and regulatory requirements. One way for electrified vehicles to have an increasing impact on fleet-level CO2 emissions is for their sales volumes to go up. This means that electrified vehicles need to deliver a complete set of vehicle level attributes like performance, Fuel Economy and range that is attractive to a wide customer base at an affordable cost of ownership. As part of “democratizing” the Hybrid and plug-In Hybrid technology, automotive manufacturers aim to deliver these vehicle level attributes with a powertrain architecture at lowest cost and complexity, recognizing that customer wants may vary considerably between different classes of vehicles. For example, a medium duty truck application may have to support good trailer tow whereas a C-sized sedan customer may prefer superior city Fuel Economy.
2017-03-28
Technical Paper
2017-01-0235
Qiuming Gong, Jimmy Kapadia
Abstract Plug-in hybrid electric vehicles (PHEV) have an EV mode driving range which can cover a portion of customer daily driving. This EV mode range affects the refuel frequency substantially compared with conventional vehicle. For a conventional vehicle, daily driving pattern, tank size and fuel economy are the factors affecting the refuel frequency. While for a PHEV, EV range is another factor would affect the results substantially. Traditional method of label range can’t represent real world driving range between fill-ups for PHEV well. How to accurately predict the PHEV refuel distance taking into account real world customer driving patterns and PHEV parameters become critical for PHEV system design and optimization. This paper presents real world big customer data based PHEV refuel distance estimation modeling. The target is to estimate PHEV refuel distance given several specific parameters such as EV range, hybrid mode fuel economy, tank size etc.
2017-03-28
Technical Paper
2017-01-0232
Nizar Khemri, Hao Ying, Joseph Supina, Fazal Syed
Abstract Realistic vehicle fuel economy studies require real-world vehicle driving behavior data along with various factors affecting the fuel consumption. Such studies require data with various vehicles usages for prolonged periods of time. A project dedicated to collecting such data is an enormous and costly undertaking. Alternatively, we propose to utilize two publicly available vehicle travel survey data sets. One is Puget Sound Travel Survey collected using GPS devices in 484 vehicles between 2004 and 2006. Over 750,000 trips were recorded with a 10-second time resolution. The data were obtained to study travel behavior changes in response to time-and-location-variable road tolling. The other is Atlanta Regional Commission Travel Survey conducted for a comprehensive study of the demographic and travel behavior characteristics of residents within the study area.
2017-03-28
Technical Paper
2017-01-0238
Velappan Shalini, Sridharan Krishnamurthy, Srinivasan Narasimhan
Abstract This study compares the model efficacy of Neural Network and Vector Auto Regression. Further it also analyses the impact of predictors controlling for total industry volume. Understanding both the methodologies has their distinctive advantages and disadvantages. Our empirical findings indicate that based on the characteristics of data such as non-stationary, non-linearity and non-normality paves the way for use of machine learning algorithm relative to econometrics technique. Our results suggest that data type and its characteristics are more important in determining the methodology than the methodology itself. In industry, econometrics methodologies are widely used due to their usage simplicity and its ability to explain the relationships in simple terms.
2017-03-28
Technical Paper
2017-01-1484
Giampiero Mastinu, Mario Pennati, Massimiliano Gobbi, Giorgio Previati, Federico Ballo
Abstract The ride comfort of three Alfa Romeo cars, namely Giulietta (1955), Alfetta (1972) and 159 (2005) has been assessed both objectively and subjectively. The three cars belong to the same market segment. The aim is to let young engineers or graduate students understand how technology has evolved and eventually learn a lesson from the assessed trend. A number of cleats have been fixed at the ground and the three cars have traversed such uneven surface. The objective assessment of the ride comfort has been performed by means of accelerometers fixed at the seat rails, additionally a special dummy developed at Politecnico di Milano has been employed. The subjective assessment has been performed by a panel of passengers. The match between objective and subjective ratings is very good. Simple mathematical models have been employed to establish a (successful) comparison between experimental and computational results. The ride comfort differs substantially among the cars.
2017-03-28
Technical Paper
2017-01-1613
Atilla Bulmus, Axel Freiwald, Chris Wunderlich
Abstract Connecting mobile communication channels to vehicles’ networks is currently attracting engineers in a wide range. Herein the desire of vehicle manufacturers to remotely execute software updates over the air (SOTA) within electronic control units (ECU) is probably the field of highest attention at the moment. Today software updates are typically done at vehicle service stations and connection the vehicles electronic network via the onboard diagnosis (OBD) interface to a service computer. Herby the duration of the update is invisible to the user, as this happens during standard service appointments. With introduction of SOTA, these updates become very convenient to the customer and can lead to higher customer satisfaction levels. SOTA can be made transparent to the user however the method of implementation can affect the user experience.
Viewing 31 to 60 of 10325