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Viewing 181 to 210 of 21653
2015-04-14
Journal Article
2015-01-0371
Rupesh Sonu Kakade, Prashant Mer
Abstract The human thermal comfort, which has been a subject of extensive research, is a principal objective of the automotive climate control system. Applying the results of research studies to the practical problems require quantitative information of the thermal environment in the passenger compartment of a vehicle. The exposure to solar radiation is known to alter the thermal environment in the passenger compartment. A photovoltaic-cell based sensor is commonly used in the automotive climate control system to measure the solar radiation exposure of the passenger compartment of a vehicle. The erroneous information from a sensor however can cause thermal discomfort to the occupants. The erroneous measurement can be due to physical or environmental parameters. Shading of a solar sensor due to the opaque vehicle body elements is one such environmental parameter that is known to give incorrect measurement.
2015-04-14
Technical Paper
2015-01-0464
Christian-Andreas Schumann, Eric Forkel, Thomas Klein, Dieter Gerlach, Egon Mueller
Abstract Total quality is becoming increasingly important for competitiveness. In order to achieve high quality, the requirements must be continuously compared with the results achieved in the process. This is done by means of measurement parameters and comparative values. The acquisition of the data requires appropriate measurement methods. The measurement methods and procedures have to be constantly developed in order to measure more precisely and to generate an even higher quality. Thus, the achieved product quality can be determined absolutely and relatively. If deviations from the planned quality parameters occur, the operator will be able to intervene immediately. The presented procedure is one of the noncontact (optical) measurement methods using CMMs, 3D scanners and 3D cameras. It is a combination of stereo photography and photogrammetry.
2015-04-14
Journal Article
2015-01-0460
Saket Kansara, Sumeet Parashar, Zhendan Xue
Abstract Decision making in engineering design is complicated, especially when dealing with high-dimensional data. Modern software tools are able to produce a large amount of data while performing optimization studies. A typical optimization problem with many objectives may produce 100s or even 1000s of Pareto Optimal solutions. It is a challenge to analyze this data and make a decision about which design/s to choose for further testing or as a final design. To tackle the problem, two data analysis techniques are used in this paper. Partitive Clustering (PC) is used to locate groups of similar designs in the dataset while Principal Component Analysis (PCA) is used to reduce the dimensionality of the data and visualize it in two and three dimensions. Although these techniques can be used independently, when used together, they prove to be a tremendous help in decision making. This paper underlines the benefit of using these two methods together.
2015-04-14
Technical Paper
2015-01-0475
Truong Nguyen, John Bell
Abstract Modern automotive electrical and electronic architecture is comprised of the battery and charging system, power distribution boxes, electronic control units, electrical devices, grounds, and the means of connecting all of these together - the wire harness or Electrical Distribution System (EDS). As automotive electrical content and complexity increases, it becomes imperative to optimize the weight, size, cost, and manufacturability of a vehicle [1]. In terms of an EDS, the most potential gain can be realized if the EDS supplier and vehicle Original Equipment Manufacturer (OEM) work together during the advanced electrical & electronic architecture development and packaging design process. Traditionally, the electrical content, harness partitioning, and packaging locations are designed by the vehicle OEM with limited advanced input from the EDS supplier.
2015-04-14
Technical Paper
2015-01-0266
Dominik Juergens, Dominik Reinhardt, Rolf Schneider, Georg Hofstetter, Udo Dannebaum, Andreas Graf
Abstract The German funded project ARAMiS included work on several demonstrators one of which was a multicore approach on large scale software integration (LSSI) for the automotive domain. Here BMW and Audi intentionally implemented two different integration platforms to gain both experience and real life data on a Hypervisor based concept on one side as well as using only native AUTOSAR-based methods on the other side for later comparison. The idea was to obtain figures on the added overhead both for multicore as well as safety, based on practical work and close-to-production implementations. During implementation and evaluation on one hand there were a lot of valuable lessons learned about multicore in conjunction with safety. On the other hand valuable information was gathered to make it finally possible to set up a cost model for estimation of potential overhead generated by different integration approaches for safety related software functions.
2015-04-14
Technical Paper
2015-01-0265
Martin Krammer, Philip Stirgwolt, Helmut Martin
Abstract The standard ISO 26262 stipulates a “top-down” approach based on the process “V” model, by conducting a hazard analysis and risk assessment to determine the safety goals, and subsequently derives the safety requirements down to the appropriate element level. The specification of safety goals is targeted towards identified hazardous events, whereas the classification of safety requirements does not always turn out non-ambiguous. While requirement formalization turns out to be advantageous, the translation from natural language to semi-formal requirements, especially in context of ISO 26262, poses a problem. In this publication, a new approach for the formalization of safety requirements is introduced, targeting the demands of safety standard ISO 26262. Its part 8, clause 6 (“Specification and management of safety requirements”) has no dedicated work product to accomplish this challenging task.
2015-04-14
Technical Paper
2015-01-0260
Ashlie B. Hocking, John C. Knight, M. Anthony Aiello, Shin'ichi Shiraishi
Abstract Software verification is a critical component of software development. Software verification techniques include different forms of testing, inspection, static analysis, and formal verification. Formal verification offers the advantage that it corresponds, at least informally, to testing all possible paths through the software. There are two primary approaches to using formal verification to establish properties of software: (a) proving properties of a formal specification, and (b) proving an implementation is a refinement of its specification. The first approach allows inference of the proven properties of the implementation provided the implementation is correct. The second approach allows inference of the correctness of the implementation. Proving properties of a specification provides a means for detecting critical design flaws early in the development process.
2015-04-14
Journal Article
2015-01-0283
Allan Lewis, Mohammad Naserian
Abstract Pedestrians A method of locating a charging target device (vehicle) in a parking lot scenario by the evaluation of Received Signal Strength Indication (RSSI) of the Dedicated Short Range Communications (DSRC) signal and Global Positioning System (GPS) data is proposed in this paper. A metric call Location Image (LI) is defined based on the RSSI received from each charger and the physical location of the parking associated to that charger. The central parking lot processor logs the GPS coordinates and LI received from the vehicle. Each pairing attempt by a vehicle loads a new LI into the central processor's database. Utilizing the LI and the proposed methods the vehicle will achieve expedited charger to system pairing while in the company of multiple chargers.
2015-04-14
Technical Paper
2015-01-0277
Seth Placke, John Thomas, Dajiang Suo
Abstract Automobiles are becoming ever more complex as advanced safety features are integrated into the vehicle platform. As the pace of integration and complexity of new features rises, it is becoming increasingly difficult for system engineers to assess the impact of new additions on vehicle safety and performance. In response to this challenge, a new approach for analyzing multiple control systems as an extension to the Systems Theoretic Process Analysis (STPA) framework has been developed. The new approach meets the growing need of system engineers to analyze integrated control systems, that may or may not have been developed in a coordinated manner, and assess them for safety and performance. The new approach identifies unsafe combinations of control actions, from one or more control systems, that could lead to an accident. For example, independent controllers for Auto Hold, Engine Idle Stop, and Adaptive Cruise Control may interfere with each other in certain situations.
2015-04-14
Technical Paper
2015-01-0278
Ingo Stürmer, Heiko Doerr, Thomas End
Managing ISO 26262 software development projects is a challenging task. This paper discusses major challenges in managing safety-critical projects from a high-level perspective, i.e. from a manager's point of view. We address managers (directors) with full project responsibility including software and hardware teams. Rather than discussing how to fulfill (technical) requirements stated by the ISO standard, we highlight major challenges and tough decisions a manager has to face on her way from project start up to delivery of the safety case. We discuss important project management topics and best practices such as negotiation issues with the contractor (OEM), selection of the appropriate functional safety manager, general ISO 262626-related project management matters, as well as contractual issues with supplier such as development interface agreement. We discuss the topics on the basis of real-life experience we collected during several ISO 26262 management projects.
2015-04-14
Technical Paper
2015-01-0279
Fumio Narisawa, Masahiro Matsubara, Masataka Nishi, Tomohito Ebina
Abstract Functions and sizes of electronic control and software systems in automotives are being increased to achieve better controllability and reduce fuel consumption. A higher safety level is also demanded, so functional-safety standards are increasingly being introduced to in-vehicle systems. In safety critical systems, failure must be diagnosed and a system transited to a safe state when hardware failure occurs. Therefore, the failure diagnosis part of the basic software that takes charge of signal inputs and outputs processing must be verified for high accountability and explanations to a third party. To diagnose failure, the hardware and software that originally operate independently need to cooperate in principle. Hardware and software cooperating systems are not straight-forward to verify, because the combinations of conditions are too numerous for testing.
2015-04-14
Technical Paper
2015-01-0280
Falco K. Bapp, Oliver Sander, Timo Sandmann, Viet Vu Duy, Steffen Baehr, Juergen Becker
Abstract Multicores, being the latest state-of-the-art technology, gain more and more importance in automotive and aerospace systems. This technology will not only be used in infotainment and non-safety-critical applications but will also be introduced in upcoming safety-critical systems. At the moment, various commercial off-the-shelf processors are available that are, however, not built for such applications. In order to ensure correct system behavior, online monitoring can be used for processors targeting infotainment or general purpose applications. The cores and other bus masters within the MPSoC compete for the exclusive use of shared resources like a memory controller. It is of high importance to provide guarantees of usage in such cases, e.g. in terms of access time and rates.
2015-04-14
Technical Paper
2015-01-0272
Ludovic Pintard, Michel Leeman, Abdelillah Ymlahi-Ouazzani, Jean-Charles Fabre, Karama Kanoun, Matthieu Roy
Abstract The complexity and the criticality of automotive electronic embedded systems are steadily increasing today, and that is particularly the case for software development. The new ISO 26262 standard for functional safety is one of the answers to these challenges. The ISO 26262 defines requirements on the development process in order to ensure the safety. Among these requirements, fault injection (FI) is introduced as a dedicated technique to assess the effectiveness of safety mechanisms and demonstrate the correct implementation of the safety requirements. Our work aims at developing an approach that will help integrate FI in the whole development process in a continuous way, from system requirements to the verification and validation phase.
2015-04-14
Technical Paper
2015-01-0275
Gokul Krithivasan, William Taylor, Jody Nelson
Abstract In ISO 26262, the top-level safety goals are derived using the Hazard Analysis and Risk Assessment. Functional safety requirements (FSRs) are then derived from these safety goals in the concept phase (ISO 26262-3:2011). The standard does not call out a specific method to develop these FSRs from safety goals. However, ISO 26262-8:2011, Clause 6, does establish requirements to ensure consistent management and correct specification of safety requirements with respect to their attributes and characteristics throughout the safety lifecycle. Hence, there are expectations on the part of system engineers to bridge this gap. The method proposed in this paper utilizes concepts from process modeling to ensure the completeness of these requirements, eliminate any external inconsistencies between them and improve verifiability.
2015-04-14
Technical Paper
2015-01-0267
Ryoichi Inada, Teppei Hirotsu, Yasushi Morita, Takahiro Hata
Abstract The ISO 26262 is a functional safety standard for road vehicles. The standard requires manufacturers to conduct quantitative assessment of the diagnostic coverage (DC) of products. The DC is defined as the percentage of failure probability covered by safety mechanisms. However, DC evaluation methods for drift faults, in which the change in element values is not constant, have not been discussed. In this paper, we propose a DC evaluation method for analog circuits with drift faults. With this method, we first parameterize the effect of drift faults onto a bounded region then split the region into safe fault, hazardous detectable fault, and hazardous undetectable fault regions. We evaluate the classification rate distribution by the area ratios of these regions.
2015-04-14
Technical Paper
2015-01-0268
Pablo Oliveira Antonino, Mario Trapp, Ashwin Venugopal
Abstract Evidence has shown that the lack of traceability between safety requirements and both architecture and failure propagation models is a key reason for the incompleteness and inconsistency of safety requirements, and, consequently, a root cause of safety incidents. In this regard, this paper presents checks for the automatic detection of incompleteness and inconsistency of safety requirements with respect to failure propagation models and architecture. First, the notion of safety requirements completeness and consistency was decomposed into small manageable pieces called Safety Requirement Completeness and Consistency Criteria. Breaking the complex notions of completeness and consistency into finer grains was important to allow systematic and precise elaboration of the completeness and consistency checks.
2015-04-14
Technical Paper
2015-01-0269
Andreas Kiep, Marco Puerschel, Chris Spielman
Abstract This paper will describe different types of short circuit conditions, how they affect power semiconductor devices, and how to detect and safely mitigate the event.
2015-04-14
Technical Paper
2015-01-0271
Fabian Joerg Uwe Koark, Christian Beul
Abstract Functional Safety engineering aligned to an international standard is already a long-lasting discussion. Nevertheless, the requirements of process conformance to assure functional safety have been detailed in description and interpretation. The ISO 26262 is seen as state-of-the-art Functional Safety engineering basement in Europe, the closer interpretation of the IEC 61508 is claimed by assessors in America and Asia. This work shows how stagnation in engineering process improvement is solved by re-engineering projects. The benefits of re-engineering are described in this context. A four month, proven-in-practice project plan is explained. The expected results of such a project are given as generic goals for similar projects. A practice report shows the realistic outcome of such a project for the Chinese automotive industry. The report shows how the motivation of the involved engineers was gained and how existing engineering documentation was used in an efficient way.
2015-04-14
Journal Article
2015-01-0302
Sagar Mody, Thomas Steffen
Abstract The idea of grid friendly charging is to use electricity from the grid to charge batteries when electricity is available in surplus and cheap. The goal is twofold: to avoid putting additional load on the electricity grid and to reduce the cost to the consumer. To achieve this, a smart meter and a tariff with variable electricity prices has to be in place. In Day Ahead tariff (DA), prices are announced in advance for the next day, and this information can be used to select the cheapest times to charge the battery by the required amount. The optimization method is very simple, and it only has to be run once per day. However, the balance of supply and demand is not fully known in advance. Therefore Real Time Pricing (RTP) tariff supplies electricity at spot market rate depending on the current balance.
2015-04-14
Technical Paper
2015-01-0301
Takayuki Shimizu, Akihisa Yokoyama, Kazuma Sato, Kunihiko Kumita
Abstract In this paper, we present an implementation of smart charging systems for plug-in electric vehicles based on off-the-shelf communication protocols for smart grids including SAE J2836/2847/J2931 standards and SEP 2.0. In this system, the charging schedule is optimized so that it supplies sufficient electricity for the next trip and also minimizes the charging cost under given time-of-use rate structures while it follows demand response events requested by a utility. Also, users can control charging schedule and check the current status of charging through application software of tablet computers. To validate the effectiveness of the developed smart charging system, we conducted experimental demonstration in which a total of 10 customers of Duke Energy regularly used our developed system for approximately one year with simulated time-of-use rate structures and demand response events.
2015-04-14
Technical Paper
2015-01-0300
Sven Bohn, Michael Agsten, Anamika Dubey, Surya Santoso
Abstract Supported by generous federal incentives and customer acceptance, the number of plug-in electric vehicles (PEVs) is increasing worldwide. A PEV can be charged both at a residential or a commercial facility by connecting it to the power grid using a charging equipment. The power demand for a single PEV charging may exceed the peak power demand of an ordinary household. Hence, an increasing number of PEVs can potentially impact the power grid massively. This paper aims to quantify the impacts of an increasing number of PEVs on power distribution circuits. A comparative analysis of the PEV impacts on the North American and European distribution circuits are presented. The study also identifies the indicators representative for quantifying the grid impacts of PEV charging. The paper further intents to clarify the interface between OEMs and utilities in achieving the common goal of a successful PEV charging and therefore a faster customer acceptance.
2015-04-14
Technical Paper
2015-01-0299
Saurav Talukdar
Abstract Control of vehicular platoons has been a problem of interest in the controls domain for the past 40 years. This problem gained a lot of popularity when the California PATH (Partners for Advanced Transportation Technology) program was operational. String stability is an important design criterion in this problem and it has been shown that lead vehicle information is essential to achieve it. This work builds upon the existing framework and presents a controller form for each follower in the string where the lead vehicle information is used explicitly to analytically demonstrate string stability. The discussion is focused on using information from immediate neighbors to achieve string stability. Recent developments in distributed control are an attractive framework for control design where each agent has access to states of the neighbors and not all agents in the network. In this work, the aim is to design sparse H2 controllers and then perform a check on string stability.
2015-04-14
Technical Paper
2015-01-0298
Wontaek Lim, Junsoo Kim, Kichun Jo, Yongwoo Jo, Myoungho Sunwoo
Abstract Parking path planning is an essential technology for intelligent vehicles. Under a confined area, a parking path has to guide a vehicle into a parking space without collision. To realize this technology, circle-based planning algorithms have been studied. The main components of these algorithms are circles and straight lines; subsequently, the parking path of the algorithm is designed by the combination of these geometric lines. However, the circle-based algorithm was developed in an open space within an unlimited parking lot width, so a feasible path cannot always be guaranteed in a narrow parking lot. Therefore, we present a parking planning algorithm based on Turning Standard Line (TSL) that is a straight line segment. The algorithm uses the TSL lines to guide sequential quadratic Béizer curves. A set of these curves from parking start to goal position creates a continuous parking path.
2015-04-14
Journal Article
2015-01-0297
Jianbo Lu, Dimitar Filev, Finn Tseng
Abstract This paper proposes an approach that characterizes a driver's driving behavior and style in real-time during car-following drives. It uses an online learning of the evolving Takagi-Sugeno fuzzy model combined with the Markov model. The inputs fed into the proposed algorithm are from the measured signals of on-board sensors equipped with current vehicles, including the relative distance sensors for Adaptive Cruise Control feature and the accelerometer for Electronic Stability Control feature. The approach is verified using data collected using a test vehicle from several car-following test trips. The effectiveness of the proposed approach has been shown in the paper.
2015-04-14
Technical Paper
2015-01-0296
Roman Schmied, Harald Waschl, Luigi del Re
Abstract Adaptive cruise control (ACC) systems allow a safe and reliable driving by adapting the velocity of the vehicle to velocity setpoints and the distance from preceding vehicles. This substantially reduces the effort of the driver especially in heavy traffic conditions. However, standard ACC systems do not necessarily take in account comfort and fuel efficiency. Recently some work has been done of the latter aspect. This paper extends previous works for CI engines by incorporating a prediction model of the surrounding traffic and a simplified control law capable for real time use in experiments. The prediction model itself uses sinusoidal functions as the traffic measurements often show periodic behavior and is adapted in every sample instant with respect to the predecessor's velocity. Furthermore, the controlled vehicle is forced to stay within a specific inter-vehicle distance corridor to avoid collisions and ensure safe driving.
2015-04-14
Journal Article
2015-01-0295
Dominik Moser, Harald Waschl, Roman Schmied, Hajrudin Efendic, Luigi del Re
Abstract Modern cars feature a variety of different driving assistance systems, which aim to improve driving comfort and safety as well as fuel consumption. Due to the technical advances and the possibility to consider vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communication, cooperative adaptive cruise control (CACC) strategies have received significant attention from both research and industrial communities. The performance of such systems can be enhanced if the future velocity of the surrounding traffic can be predicted. Generally, human driving behavior is a complex process and influenced by several environmental impacts. In this work a stochastic model of the velocity of a preceding vehicle based on the incorporation of available information sources such as V2I, V2V and radar information is presented. The main influences on the velocity prediction considered in this approach are current and previous velocity measurements and traffic light signals.
2015-04-14
Technical Paper
2015-01-0294
Takamasa Koshizen, MAS Kamal, Hiroyuki Koike
Abstract Our study unveils what smart cars are needed to minimize congestion by traffic stability. We have previously considered pacer cars with single lane road networks based on a car following model, e.g. adaptive cruise control (ACC). However, pacer cars may have a limitation with multi-lane roadways in terms of lane distribution of traffic and shockwave suppression. Therefore, we motivate building a new smart car which extends the capability of pacer cars allowing lane changing at the timing of congestion detection. In essence, the congestion detection plays a role of adjusting the (time) headway of smart cars to determine whether lane changes should be undertaken. Lane changes can be used to uniformize (or equalize) lane distribution for traffic (flow) stability. Our simulation study has suggested that the proposed smart cars enforce the capability of traffic stability more than manual and pacer cars.
2015-04-14
Technical Paper
2015-01-0293
Yaamini Devi Loganathan
Abstract Indian automobile production increased at a CAGR of 12.2% over FY05-FY13, with a decline in Commercial Vehicle (CV) growth rate during FY09 and FY13. Globally, automotive industry suffered a decline in FY09 due to the global financial crisis and again on a decline in FY12 due to the European sovereign debt crisis. Apart from the global events, there are various internal risks the Indian OEMs need to consider: 1) regulatory risk due to excise duty hikes, decontrol of fuel pricing, etc., 2) market risks due to currency, inflation, interest rates, material cost, 3) industry risks due to increased competition, price war, etc. In this scenario, Indian Original Equipment Manufacturers (OEMs) need to constantly recalibrate their strategies to the changing market dynamics and associated risks. A research on megatrends affecting the Indian CV industry has identified more focus on Total Cost of Ownership (TCO) as one of the megatrend.
2015-04-14
Technical Paper
2015-01-0290
Amin Tahmasbi-Sarvestani, Hadi Kazemi, Yaser P. Fallah, Mohammad Naserian, Allan Lewis
Abstract Pedestrians account for a significant ratio of traffic fatalities; as a result, research on methods of reducing vehicle-pedestrian crashes is of importance. In this paper, we describe a system architecture that allows the use of vehicle-to-pedestrian (V2P) communication as a means of generating situational awareness and eventually predicting hazards and warning drivers and pedestrians. In contrast, vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communication for safety applications, V2P has not received much attention. One major reason for this lack of attention had been the unavailability of communication mechanisms between pedestrians and vehicles. Recent advances in enabling Wi-Fi and dedicated short range communication (DSRC) based communication using smart-phones is changing this picture. As a result, V2P communication can be considered as a possible solution.
2015-04-14
Journal Article
2015-01-0288
Virendra Kumar, William Whyte
Abstract IEEE Standard 1609.2-2013, Security Services for Applications and Management Messages for Wireless Access in Vehicular Environments (WAVE), specifies its data structures and encoding using a proprietary language based on that used in the Internet Engineering Task Force (IETF)'s Transport Layer Security (TLS) specification. This approach is believed to allow fast encoding and decoding, but is non-standard, is not proved to be complete, lacks automatic tools for generation of codecs, and is difficult to extend. For these reasons, the 1609 Working Group approved the use of Abstract Syntax Notation 1 (ASN.1) for future versions of 1609.2, so long as ASN.1 did not significantly degrade performance. This paper is the first publication of the results of a performance analysis carried out to determine whether ASN.1-based encoding was in fact acceptable.
Viewing 181 to 210 of 21653

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