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2015-04-14
Journal Article
2015-01-0156
Alexandr Murashkin, Luis Silva Azevedo, Jianmei Guo, Edward Zulkoski, Jia Hui Liang, Krzysztof Czarnecki, David Parker
The number of software-intensive and complex electronic automotive systems is continuously increasing. Many of these systems are safety-critical and pose growing safety-related concerns. ISO 26262 is the automotive functional safety standard developed for the passenger car industry. It provides guidelines to reduce and control the risk associated with safety-critical systems that include electric, electronic, and programmable parts. The standard uses the concept of Automotive Safety Integrity Levels (ASILs) to decompose and allocate safety requirements of different stringencies to the elements of a system architecture in a top-down manner. ASILs are assigned to system-level hazards and then iteratively decomposed and allocated to relevant subsystems and components. ASIL decomposition rules may give rise to multiple alternative allocations, leading to an optimization problem of finding cost-optimal allocations.
2015-04-14
Journal Article
2015-01-0501
Dengfeng Wang, Rongchao Jiang
The cost of fuel for commercial trucks takes up a great proposition in the total vehicle operating costs. In order to improve the power performance and fuel economy of a domestic self-dumping truck, an optimization matching method of the powertrain system was presented in this paper. A vehicle performance simulation model of this self-dumping truck was established using AVL-Cruise software. Then the power performance and fuel economy simulations were executed according to China National Standard GB/T 12543-2009 “Acceleration performance test method for motor vehicles” and GB/T27840-2011 “Fuel consumption test methods for heavy-duty commercial vehicles”. Moreover, the simulation results were compared with the road test results, which were measured on proving ground, to verify the validity of the vehicle performance simulation model.
2015-04-14
Journal Article
2015-01-0460
Saket Kansara, Sumeet Parashar, Zhendan Xue
Increased sophistication of engineering simulation tools, availability of computing power and demand for optimization is steering engineers towards multi-objective and multi-disciplinary formulation. It is becoming common to see problem setup with hundreds of input parameters, many objective functions and constraints. While modern optimization algorithms and software tools are able to handle large scale problems and generate even larger datasets, it is a challenge to analyze such large data sets and make effective decisions. Decision making is especially challenging when one has multiple objectives of conflicting nature. Pareto frontier solutions for two or three objective space are easy to visualize and comprehend, however, as the number of objectives increase, it becomes more and more difficult to understand and analyze trade-offs from the results coming out of optimization.
2015-04-14
Journal Article
2015-01-0495
Shohei Mikami, Georgi Chakmakov
Designing a lightweight and high-strength engine product is universally important from the standpoints of fuel consumption, power, and cost; however, it is difficult to find an optimal solution accomplishing these characteristics in products such as the cylinder heads that are simultaneously affected by a thermal load and various mechanical loads. We focused on an optimization means called “nonparametric optimization” and created a method of cylinder head design that utilized it. Our optimization process was divided into topological optimization and shape optimization. In the topological optimization process, we searched for a structure with the highest theoretical stiffness in the given design space. This provided an efficient structure when pursuing both lightweight and high-strength characteristics in the subsequent shape optimization process. Strain energy and displacement of the combustion chamber were used as the parameters for controlling stiffness.
2015-04-14
Journal Article
2015-01-0489
Jason Rogers
A Catia-and-Excel-based predictive tool was developed to predict trunk spring movement for preventing recurrence of a noise problem. While effective, the tool could not completely explain measured CBU results. Since design data was used for the study, it was hypothesized that the difference between study and actual results was related to tolerance variation on the actual vehicle. Using Siemens VSA software, the vehicle was built and simulated virtually with tolerances using a Monte Carlo model. The study found that the hypothesis was correct; tolerance variation was fully responsible for the differences. The study also allowed accurate prediction of failure rates.
2015-04-14
Journal Article
2015-01-0488
Andreea Elena Balau, Dennis Kooijman, Ignacio Vazquez Rodarte, Norbert Ligterink
The goal of this work is to develop a tool that stochastically generates drive cycles based on measured data, with the purpose of testing light duty vehicles in a simulation environment or on a test-bench for type approval testing. The WLTC database was used as input data. This database was created with the help of a number of European countries that collaborated and provided real world driving measurements. Consequently cycles that contain typical accelerations per velocity and road types are generated, such that these cycles are representative to real driving behaviour. The stochastic drive cycle generator is developed in Matlab and is based on Markov processes. Two different stochastic generators are used: one for generating the road type and one for generating the vehicle acceleration.
2015-04-14
Journal Article
2015-01-0500
Emilio Larrodé, Alberto Torne, Alberto Fraile
This paper is collaboration between the Research Group on Sustainable Means of Transport and Systems (SMITS) of the University of Zaragoza (Spain) and the Spanish company, Zytel Automotive S.L. (ZYTEL). The analysis and decision making on design, behaviour and use of a prototype electric vehicle is the main focus has been pursued in this paper. It was modelled a prototype electric vehicle, called Gorila EV, as from the software tool Adams/Car (MSC Software Corporation). The way it decided to tackle this paper was by Computer Aided Engineering (CAE). Conduct an analysis of the vehicle by CAE allows increasing the quickness and convenience when getting results and reduce costs incurred testing with real prototypes. In this study it considers urban driving, where the vehicle trajectory is constrained by the infrastructure (road signs) and other vehicles (traffic).
2015-04-14
Journal Article
2015-01-0603
Robert A. Smith, Mikel Petty
Dynamic Mechanical Analysis Evaluation of the Dimensional Stability of Poly(butylene terephthalate) with Glass Fiber Filler Robert A. Smith and Mikel Petty Delphi Electrical/Electronic Architecture 4551 Research Parkway Warren, Ohio 44483 Sealed connections are critical for the safe operation of all vehicles; particularly with the high voltages (350V) of HEV and EVs. Leakage of water or petroleum-based contaminants into connections could cause immediate cessation of operation risking a catastrophic collision. Connections consist of various designs which require a sufficient hold force between the male and female components to enable gasket sealing. Loss of hold force or distortion from dimensional instability may lead to leakage through the gasket.
2015-04-14
Journal Article
2015-01-0869
Ningsheng Qiao, Chandrasekar Krishnamurthy, Nicholas Moore
Air-fuel ratio cylinder imbalance is a condition where the air-fuel ratio in one or more cylinders is different than the other cylinders. When air-fuel ratio cylinder imbalance occurs in one or more cylinders the fuel delivery system is unable to maintain a proper vehicle emission level. It is required for on-board diagnostics to detect air-fuel ratio cylinder imbalance levels which cause the fuel delivery system to be unable to maintain vehicle emissions at or below 1.5 times of any of the applicable FTP (Federal Test Procedure) emission standards. Currently California Air Resources Board (CARB) only requires on-board diagnostics to detect exhaust bank specific air-fuel ratio cylinder imbalance. In the near future CARB will require on-board diagnostics to detect cylinder specific air-fuel ratio cylinder imbalance. This paper presents a non-intrusive approach on determining single cylinder air-fuel ratio imbalance identification (ID) with an oxygen sensor.
2015-04-14
Journal Article
2015-01-1306
Jeremy S. Neubauer, Eric Wood, Ahmad Pesaran
Battery second use – putting used plug-in electric vehicle (PEV) batteries into a secondary service following their automotive tenure – has been proposed as a means to decrease the cost of PEVs while providing low cost energy storage to other fields (e.g. electric utility markets). Under the support of the U.S. Department of Energy’s Vehicle Technologies Office, the National Renewable Energy Laboratory (NREL) has conducted a comprehensive study of this topic. This presentation will focus on a subset of that study focusing on battery degradation and value, specifically addressing the following key questions: How long will PEV batteries last in automotive service? How healthy will PEV batteries be when they leave automotive service? How long will retired PEV batteries last in second-use service? How can we best predict the second-use lifetime of a used automotive battery? What’s the value of a second-use battery?
2015-03-30
Technical Paper
2015-01-0101
Piyapong Premvaranon, Jenwit Soparat, Apichart Teralapsuwan, Wuttipong Sritham, Chi-na Benyajati, Nathapol Taweewong
Abstract Due to recent oil price crisis and an ever-increasing public awareness on environmental issues, an interest in electric vehicles (EV) has increased tremendously in Thailand and other Asian countries over the last few years. In this study, a prototype of 9-metre battery electric vehicle (BEV) bus was chosen as a vehicle of interest to undergo a series of field test by operating the lead acid battery powered electric bus in order to estimate a power demand of the bus as well as to evaluate a battery performance characteristic Two different types of battery were employed in this study i.e. a flooded-type deep cycle lead acid battery and a valve regulated lead acid (VRLA) battery. The effect of different driving modes available from the drive motor i.e. normal, max power, max range, as well as regenerative braking feature would be investigated while an influence of drivers were also taken into account to ensure the repeatability of the obtained results.
2015-03-30
Technical Paper
2015-01-0102
Jenwit Soparat, Wuttipong Sritham, Apichart Teralapsuwan, Chadchai Srisurangkul, Chi-na Benyajati
Abstract In this study, a prospect of employing electric fans in a battery cooling system was investigated by means of a computational fluid dynamic (CFD) analysis. The concept was to have the fans to stimulate appropriate air flows inside the battery compartment. A rear utility space behind back passenger seats was dedicated for the battery compartment containing 100 cells of Lithium Ion batteries. Due to limited working space, a battery arrangement was conceived as a double stacking configuration. In computational analysis, the heat source model of employed batteries was obtained from the experimental work. Several potential designs of cooling patterns were investigated. The design parameters of interest were locations of inlet/outlet, and air flow rate. The performance criteria of cooling system were resulting battery temperatures, temperature distribution uniformity, required pump pressure, and structural integrity.
2015-03-30
Technical Paper
2015-01-0124
Raksit Thitipatanapong, Sunhapos Chantranuwathana, Nuksit Noomwongs, Pornporm Boonporm, Petch Wuttimanop, Sanya Klongnaivai
Abstract The road accident is major concern around the world, so do Thailand. It is caused by three main factors: man, vehicle and infrastructure. The most important part that accounts the safety of vehicle is human. With experiences and careful driver, the accident could be diminished. So that the vehicle monitoring systems are the vital tools to screen out the inexperience or aggressive driver. In this paper, we state the problem about the dangerous driving behavior by monitoring lateral and longitudinal acceleration. For this purpose, the inertial measurement unit should be applied but it is inconvenient to install in the vehicle. Consequently, the vehicle monitoring system were developed based on novel consumer grade multi-satellite navigation receivers and were compared to Racelogic Video V-Box system in controlled condition tested track. The incidents were virtually detected and reviewed. The incident detection algorithm were proposed and tested alongside with receivers.
2015-03-30
Technical Paper
2015-01-0094
Supakit Rooppakhun, Pornporm Boonporm, Worawat Puangcha-um
Abstract In this study, the method of analyzing the thin-wall crashing box of impact attenuator for student formula is proposed by the means of simulation and validation following Formula Society of Automotive Engineers-SAE rules. The analysis was performed based on computerized simulation software for calculated the absorption capacity of the simple and multiple cell of thin-walled tubes. The effect of thin-wall thickness consisted of 1.2 mm, 1.6 mm and 2.0 mm was also evaluated. The simulation results as energy absorption, crashing force efficiency, and absorbed energy per unit mass were identified among nine patterns. According to the results, the increase of interior cell number and the wall thickness contribute the absorbed energy ability. However, the increment of wall thickness lead to the increase of crashing force magnitude. Regarding the kinetic energy, a 2×2 multiple cell box with the thickness of 2 mm is designated for construction and verify.
2015-03-30
Technical Paper
2015-01-0123
Raksit Thitipatanapong, Petch Wuttimanop, Sunhapos Chantranuwathana, Sanya Klongnaivai, Pornporm Boonporm, Nuksit Noomwongs
Abstract The road accident is major problem around the world and also in Thailand, The main cause is concerning the driving behavior e.g. uncarefulness, aggression, drowsiness and etc. Dangerous driving is categorized by means of lateral vehicle dynamics when the turning or lane changing is performed, and longitudinal one if the braking or rapid acceleration is occurred. For this reason, we developed the vehicle monitoring system based on novel consumer grade multi-satellite navigation receivers and proposed the lateral acceleration estimation from these data. The system were tested within controlled condition tested track. The multiple satellite system, GPS and multi-GNSS: GPS+Glonass and GPS+Beidou were tested and compared to the reference inertial measurement unit (IMU) As results, the maximum lateral acceleration in tested track were chosen and compared with reference IMU.
2015-03-10
Technical Paper
2015-01-0054
Guangming Liu, Minggao Ouyang, Languang Lu, Jian qiu Li
Abstract Electric vehicle (EV) is a worldwide researching focus due to its environmental friendliness, but the inaccurate Remaining Driving Range (RDR) estimation hinders the EVs' popularity, and an accurate determination of the battery Residual Usable Energy (RUE) is the key factor to obtain a precise RDR value. A common RUE estimation method is based on State-of-Charge (SOC) estimation, in which the RUE is proportionally related to the current SOC. However, the battery voltage varies significantly under real-world conditions, and the traditional method results in certain estimation errors. An adaptive RUE prediction method (AEP) is introduced in this paper, in which the dynamic voltage is predicted based on the future discharge profile and a battery model, while the RUE is then calculated by the predicted voltage and current sequences.
2015-03-10
Technical Paper
2015-01-0023
Sung Hoon Kim, Jung Su Kim, Dian Nugraha, Vincent Wan, Il Hong Suh
Abstract It has become an important trend to implement safety-related requirements in the road vehicles. Recent studies have shown that accidents, which occurred when drivers are not focused due to fatigue or distractions, can be predicted in advance when using safety features. Advanced Driver Assistance Systems (ADAS) are used to prevent this kind of situation. Currently, many major tiers are using a DSP chip for ADAS applications. This paper suggests the migration from a DSP configuration to a Microcontroller configuration for ADAS application, for example, using a 32bit Multi-core Microcontroller. In this paper, the following topics will be discussed. Firstly, this paper proposes and describes the system block diagram for ADAS configuration followed by the requirements of the ADAS system. Secondly, the paper discusses the current solutions using a DSP. Thirdly, the paper presents a system that is migrated to a Multi-core microcontroller.
2015-03-10
Technical Paper
2015-01-0058
Robin Smit, Phil Kingston
Abstract Reliable motor vehicle emission predictions are needed to ensure sound policy decisions. This study reports on a comparison between measured in-tunnel fleet emissions and predictions made with two new Australian vehicle emission software programs (COPERT Australia and PΔP) for one air pollutant: nitrogen oxides (NOx). Measurements were taken from a 6.8 km tolled motorway tunnel that links several major roads in Brisbane, Australia. The validation study suggests that modelled vehicle emissions of NOx are similar to those measured in the tunnel with a prediction error less than ±25% for both light-duty and heavy-duty vehicles. A possible reason for the difference is a suspected younger and cleaner fleet in the tunnel as compared with the Queensland average fleet. Further analysis of license plate information is anticipated to verify this.
2015-03-10
Technical Paper
2015-01-0039
Ryuzo Hayashi, Hajime Tsuyuki, Masao Nagai
Abstract This study proposes a method for presenting maneuver request information of accelerator pedal to a driver via the accelerator pedal itself. By applying periodic force like vibration on an accelerator pedal, information is transferred to the driver without displacing the accelerator pedal. In this study, the authors focus on a saw-tooth wave as the periodic force. When the saw-tooth-waved force is applied on the accelerator pedal, a human driver feels as if the accelerator pedal is knocked by someone periodically. In addition, information about the quantity of requested maneuver can be transferred by the amplitude of the saw-tooth wave. Based on these facts, the saw-tooth wave is modified and optimized empirically with ten human drivers so that the information of direction is transferred most reliably. In addition, the relationship between the amplitude of the saw-tooth wave and requested quantity of the pedal maneuver that the drivers feel is formulated.
2015-03-10
Technical Paper
2015-01-0041
Shashank Arora, Weixiang Shen, Ajay Kapoor
Abstract Battery packs are highly sensitive to operating environment and their interactions with other systems in electric vehicles (EVs). Control of the operating environment and understanding of the influences of these interactions on battery performances are required to maximise their energy capacity and cycle life in EVs. This paper presents a modified parameter diagram (P-diagram) which is a part of systematic effort to design a robust battery pack. In the modified P-diagram, the physical inputs that affect the performance of a battery pack are identified and categorised into noise factors and control factors, where the former limits the performance and the latter can be used to improve it. Different noise factors are conceptually analysed in conjunction with various control factors and graded according to their relative influence on the performance of a battery pack. The performance is measured in terms of ideal function output and potential error states.
2015-03-10
Technical Paper
2015-01-0063
Ambarish Kulkarni, Ajay Kapoor, Shashank Arora
Abstract Increased demands on rare earth fossil fuels and the global warming have led to development of alternative technology vehicles. Electrical vehicle (EV) is chosen as one of the alternative technology to overcome these hindrances. In EVs the battery and the motor are the two most critical components used for generating the required power output. In this paper, work was done for selection battery technology and relevant packaging for a small car. The work done is described in four stages: i) battery selection based on literature, ii) car selection based on virtual reality (VR) study iii) battery package design, and iv) finally specification sheet was developed for an EV. Key Objectives considered for the battery selection are: i) minimal maintenance, ii) modular and scalable, iii) high energy density, iv) optimized thermal management, and v) low cost implications.
2015-03-10
Technical Paper
2015-01-0013
Li Sun
The design of the onboard powertrain energy storage system (ESS) plays a vital role in laying out performance specifications for an electric vehicle (EV). One solution to address the relatively low power density problem of battery being sole storage source is to hybridize ESS with higher power density sources such as supercapacitor via a buck-boost converter to electrically regulate each power flow bi-directionally. This paper proposes a simple but innovative method with the aim of guiding EV designers of logically choosing the optimal size and ratio of each power source to form a hybrid energy storage system (HESS), when considering a set of constraints in practice such as the presence of buck-boost converter.
2015-02-27
Article
U.S. Secretary of Transportation Anthony Foxx discussed a wide range of technology and safety issues following his SAE Government/Industry Meeting keynote speech, including cybersecurity, autonomous vehicles, and international harmonization of safety standards.
2015-02-27
WIP Standard
AS81511A
This specification covers four series of electrical connectors (plugs and receptacles) with removable crimp contacts and accessories (see 6.1). AS81511 connectors are not recommended for new design. All AS81511 detail sheets that specified class D and/or H have been cancelled without replacement, therefore all class D and H requirements have been deleted from this specification.
2015-02-26
Article
The system is based on Elbit’s ClearVision EFVS for fixed-wing platforms and provides helicopter pilots with increased situational awareness.
2015-02-26
Standard
J1113/13_201502
This SAE Standard specifies the test methods and procedures necessary to evaluate electrical components intended for automotive use to the threat of Electrostatic Discharges (ESDs). It describes test procedures for evaluating electrical components on the bench in the powered mode and for the packaging and handling non-powered mode. A procedure for calibrating the simulator that is used for electrostatic discharges is given in Appendix A. An example of how to calculate the RC Time Constant is given in Appendix B Functional Performance Status Classifications for immunity to ESD and Sensitivity classificatins for ESD sensitive devices are given in Appendix C. Sensitivity classifications for ESD sensitive devices are given in Appendix B.
2015-02-25
Article
The inventors of semiconductor chips or electronic parts most likely never imagined that over 50 years later, the aviation, space, and defense industries would be faced with the availability or proliferation of counterfeit electronic parts in their supply chains.
2015-02-24
Article
Conventional vehicle radios are morphing into increasingly powerful infotainment systems, prompting a need for storage to hold apps, navigation, and other data. Flash storage supplier SanDisk is beefing up its automotive portfolio with automotive grade chips and memory cards to satisfy that need.
2015-02-24
Article
What do rice cookers have to do with lowering the price of hybrid and electric cars? In this episode of SAE Eye on Engineering, Senior Editor Lindsay Brooke looks at a tiny electrical device called the IGBT (Insulated Gate Bipolar Transistor).
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