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Viewing 91 to 120 of 16152
2015-04-14
Technical Paper
2015-01-1362
Chao Li, Il Yong Kim
Abstract A bumper system plays a significant role in absorbing impact energy and buffering the impact force. Important performance measures of an automotive bumper system include the maximum intrusions, the maximum absorbed energy, and the peak impact force. Finite element analysis (FEA) of crashworthiness involve geometry-nonlinearity, material-nonlinearity, and contact-nonlinearity. The computational cost would be prohibitively expensive if structural optimization directly perform on these highly nonlinear FE models. Solving crashworthiness optimization problems based on a surrogate model would be a cost-effective way. This paper presents a design optimization of an automotive rear bumper system based on the test scenarios from the Research Council for Automobile Repairs (RCAR) of Europe. Three different mainstream surrogate models, Response Surface Method (RSM), Kriging method, and Artificial Neural Network (ANN) method were compared.
2015-04-14
Technical Paper
2015-01-1364
Tao Wang, LIangmo Wang, Yuanlong Wang, Xiaojun Zou, Fuxiang Guo
Abstract The design of aluminum foam reinforced thin-walled tubes has garnered much interest recently due to the high energy absorption capacity of these tubes. As a new kind of engineering composite material, aluminum foam can hugely increase the crashworthiness capacity without sacrificing too much weight. In this paper, axisymmetric thin-walled hollow tubes with four different kinds of cross-sections (circular, square, hexagonal and octagonal) are studied to assess their performance for crashworthiness problems. It is found that the tube with square cross-section has the best crashworthiness performance under axial impact. To seek optimal designs of square aluminum foam reinforced thin-walled tubes, a surrogate modeling technique coupled with a multi-criteria particle swarm optimization algorithm has been developed, to maximize specific energy absorption (SEA) and minimize peak crash force (PCF).
2015-04-14
Technical Paper
2015-01-1384
Richard Young, Jing Zhang
Abstract In this age of the Internet of Things, people expect in-vehicle interfaces to work just like a smartphone. Our understanding of the reality of in-vehicle interfaces is quite contrary to that. We review the fundamental principles and metrics for automotive visual-manual driver distraction guidelines. We note the rise in portable device usage in vehicles, and debunk the myth of increased crash risk when conversing on a wireless device. We advocate that portable electronic device makers such as Apple and Google should adopt driver distraction guidelines for application developers (whether for tethered or untethered device use in the vehicle). We present two design implications relevant to safe driving. First, the Rule of Platform Appropriateness: design with basic principles of ergonomics, and with driver's limited visual, manual and cognitive capacity, in mind. Second, the Rule of Simplicity: thoughtful reduction in the complexity of in-vehicle interfaces.
2015-04-14
Technical Paper
2015-01-1387
Richard Young
Abstract This study revises the odds ratios (ORs) of secondary tasks estimated by Virginia Tech Transportation Institute (VTTI), who conducted the 100-Car naturalistic driving study. An independent and objective re-counting and re-analysis of all secondary tasks observed in the 100-Car databases removed misclassification errors and epidemiological biases. The corrected estimates of secondary task crude OR and Population Attributable Risk Percent (PAR%) for crashes and near-crashes vs. a random baseline were substantially lower for almost every secondary task, compared to the VTTI estimates previously reported. These corrected estimates were then adjusted for confounding from demographics, time of day, weekday-weekend, and closeness to junction by employing secondary task counts from a matched baseline from a later VTTI 100-Car analysis. This matched baseline caused most OR estimates to decline even further.
2015-04-14
Journal Article
2015-01-1386
Devin SJ Caplow-Munro, Helen Loeb, Venk Kandadai, Flaura Winston
Abstract Inadequate situation awareness and response are increasingly recognized as prevalent critical errors that lead to young driver crashes. To identify and assess key indicators of young driver performance (including situation awareness), we previously developed and validated a Simulated Driving Assessment (SDA) in which drivers are safely and reproducibly exposed to a set of common and potentially serious crash scenarios. Many of the standardized safety measures can be calculated in near real-time from simulator variables. Assessment of situation awareness, however, largely relies on time-consuming data reduction and video coding. Therefore, the objective of this research was to develop a near real-time automated method for analyzing general direction and location of driver's gaze in order to assess situation awareness.
2015-04-14
Journal Article
2015-01-1381
Jason P. Huczek, R. Rhoads Stephenson
Abstract The Department of Transportation (DOT) National Highway Traffic Safety Administration (NHTSA) awarded a contract to Southwest Research Institute (SwRI) to conduct research and testing in the interest of motorcoach fire safety. The goal of this program was to develop and validate procedures and metrics to evaluate current and future detection, suppression, and exterior fire-hardening technologies that prevent or delay fire penetration into the passenger compartment of a motorcoach - in order to increase passenger evacuation time. The program was initiated with a literature review and characterization of the thermal environment of motorcoach fires and survey of engine compartments, firewalls, and wheel wells of motorcoaches currently in North American service. These characterizations assisted in the development of test methods and identification of the metrics for analysis.
2015-04-14
Technical Paper
2015-01-1380
Kumar Kumar
Abstract According to the National Fire Protection Agency (NFPA), from the most recent available data, it was estimated that there were 164,000 highway vehicle fires in 2013 causing roughly 300 civilian fire deaths, 925 civilian fire injuries and $1.1 billion in property damages [1]. In a modern automobile, the plastics content is dramatically higher than it was in 1972, when Federal Motor Vehicle Safety Standard (FMVSS) 302 was implemented [2]. FMVSS 302 applies only to materials in the passenger compartment and was put in place to address accidental fires started from sources such as cigarettes, matches, etc. There has never been any regulation for the plastic materials used outside the vehicle interior, including those used in under-the-hood (UTH) applications, and this is true even for today's automobiles.
2015-04-14
Technical Paper
2015-01-1382
Lisa Schei Blikeng, Siril Hegén Agerup
Abstract This paper is based on the bachelor thesis “Fire in electric cars” [1] 2013, written in Norwegian. The number of electric vehicles has increased significantly in recent years. Today, there are more than 35,000 electric cars in Norway, and the government's goal is 200,000 cars by 2020. [3] The main question investigated was: What happens when the lithium-ion battery pack ignites? The major part of this assignment was to perform a full-scale fire experiment with a modern and drivable electric car. This experiment took place in February 2013, when a Peugeot iOn 2012 model was set on fire. The car burned out without any attempt being made to extinguish the fire. We had to supply much heat from the external heat source to achieve thermal runaway in the cells. Observations and results from the experiment indicated that fire in the lithium-ion battery cells consists of two phases.
2015-04-14
Journal Article
2015-01-1383
Andrew Blum, Richard Thomas Long
Abstract Fires involving cars, trucks, and other highway vehicles are a common concern for emergency responders. In 2013 alone, there were approximately 188,000 highway vehicle fires. Fire Service personnel are accustomed to responding to conventional vehicle (i.e., internal combustion engine [ICE]) fires, and generally receive training on the hazards associated with those vehicles and their subsystems. However, in light of the recent proliferation of electric drive vehicles (EDVs), a key question for emergency responders is, “what is different with EDVs and what tactical adjustments are required when responding to EDV fires?” The overall goal of this research program was to develop the technical basis for best practices for emergency response procedures for EDV battery incidents, with consideration for suppression methods and agents, personal protective equipment (PPE), and clean-up/overhaul operations.
2015-04-14
Journal Article
2015-01-1379
Hideki Matsumura, Shinichiro Itoh, Kenichi Ando
Abstract Lithium-ion cells are being used in an increasing number of electric and hybrid vehicles. Both of these vehicle types contain many cells. Despite various safety measures, however, there are still reports of accidents involving abnormal heat, smoke, and fire caused by thermal runaway in the cells. If thermal runaway in one cell triggers that of another and thus causes thermal runaway propagation, this can lead to rupture of the battery pack, car fire, or other serious accidents. This study is aimed to ensure the safety of vehicles with lithium-ion cells by clarifying such accident risks, and so we investigated the process of thermal runaway propagation. In the experiment, we created a battery module made of seven laminate-type cells tightly stacked one on another. Then, we induced thermal runaway in one of the cells, measured the surface temperatures of the cells, and collected video data as the process developed. As a result, all of the seven cells underwent thermal runaway.
2015-04-14
Technical Paper
2015-01-1413
Louis Tijerina, Michael Blommer, Reates Curry, Radhakrishnan Swaminathan, Dev Kochhar, Walter Talamonti
Abstract This paper investigates the effects on response time of a forward collision event in a repeated-measures design. Repeated-measures designs are often used in forward collision warning (FCW) testing despite concerns that the first exposure creates expectancy effects that may dilute or bias future outcomes. For this evaluation, 32 participants were divided into groups of 8 for an AA, BB, AB, BA design (A= No Warning; B=FCW alert). They drove in a high-fidelity simulator with a visual distraction task. After driving 15 min in a nighttime rural highway environment, a forward collision threat arose during the distraction task (Period 1). A second drive was then run and the forward collision threat was repeated again after ∼10 min (Period 2). The response times from these consecutive events were analyzed.
2015-04-14
Technical Paper
2015-01-1410
Shotaro Odate, Kazuhiro Daido, Yosuke Mizutani
Abstract According to the North American National Automotive Sampling System Crashworthiness Data System (NASS/CDS), approximately one-half of all accidents during driving are of the secondary collision pattern in which the collision event involves the occurrence of secondary collision. Accidents involving impact to a stopped vehicle (chain-reaction collisions) have increased to approximately 3% of all accidents in North America, and although the rate of serious injury is low, cases have been reported of accidents in which cervical sprain occurs as an after-effect[1]. In order to mitigate these circumstances, research has been conducted on systems of automatic braking for collisions. These systems apply brakes automatically when a first collision has been detected in order to avoid or lessen a second collision. Research on automatic collision braking systems, however, has not examined the multiple collisions parked [1, 2].
2015-04-14
Technical Paper
2015-01-1411
Caroline Crump, David Cades, Robert Rauschenberger, Emily Hildebrand, Jeremy Schwark, Brandon Barakat, Douglas Young
Abstract Advanced Driver Assistive System (ADAS) technologies have been introduced as the automotive industry moves towards autonomous driving. One ADAS technology with the potential for substantial safety benefits is forward collision warning and mitigation (FCWM), which is designed to warn drivers of imminent front-end collisions, potentiate driver braking responses, and apply the vehicle's brakes autonomously. Although the proliferation of FCWM technologies can, in many ways, mitigate the necessity of a timely braking response by a driver in an emergency situation, how these systems affect a driver's overall ability to safely, efficiently, and comfortably operate a motor vehicle remains unclear. Exponent conducted a closed-course evaluation of drivers' reactions to an imminent forward collision event while driving an FCWM-equipped vehicle, either with or without a secondary task administered through a hands-free cell phone.
2015-04-14
Journal Article
2015-01-1408
Kristofer D. Kusano, Hampton C. Gabler
Abstract Intersection crashes are a frequent and dangerous crash mode in the U.S. Emerging Intersection Advanced Driver Assistance Systems (I-ADAS) aim to assist the driver to mitigate the consequences of vehicle-to-vehicle crashes at intersections. In support of the design and evaluation of such intersection assistance systems, characterization of the road, environment, and drivers associated with intersection crashes is necessary. The objective of this study was to characterize intersection crashes using nationally representative crash databases that contained all severity, serious injury, and fatal crashes. This study utilized four national crash databases: the National Automotive Sampling System, General Estimates System (NASS/GES); the NASS Crashworthiness Data System (CDS); and the Fatality Analysis Reporting System (EARS) and the National Motor Vehicle Crash Causation Survey (NMVCCS).
2015-04-14
Technical Paper
2015-01-1405
Guanjun Zhang, Feng Yu, Zhigao OuYang, Huiqin Chen, Zhonghao Bai, Libo Cao
Abstract The combination of passive and active vehicle safety technologies can effectively improve vehicle safety. Most of them predict vehicle crashes using radar or video, but they can't be applied extensively currently due to the high cost. Another collision forecasting method is more economic which is based on the driver behavior and vehicle status, such as the acceleration, angular velocity of the brake pedal and so on. However, the acceleration and angular velocity of the brake pedal will change with the driver and the vehicle type. In order to study the effect of different drivers and vehicle types on the braking acceleration and angular velocity of the brake pedal, six volunteers were asked to drive five vehicles for simulating the working conditions of emergency braking, normal braking, inching braking and passing barricades under different velocities. All the tests were conducted on asphalt road, and comprehensive experimental design was used to arrange tests.
2015-04-14
Technical Paper
2015-01-1406
Mikael Ljung Aust, Lotta Jakobsson, Magdalena Lindman, Erik Coelingh
Abstract This paper first discusses the advancement and challenges in the areas of developing Collision Avoidance Systems, or CAS. CAS have been on the market for a decade, and their development has been rapid. Starting with forward collision warning with brake support, targeting vehicles moving in the same direction in front of the car, CAS now cover pedestrians and cyclists in front of the car as well as vehicles standing still and even some situations of approaching vehicles in crossings. This development up to date is described and discussed according to the challenge areas of detection, decision strategy and intervention strategy. Next, the paper discusses assessment of system effects on driving safety. Numerous studies have tried to predict the effect of various CAS, and the real world effect of these systems has been shown to be significant.
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
2015-01-0273
Helmut Martin, Martin Krammer, Bernhard Winkler, Christian Schwarzl
Abstract Although the ISO 26262 provides requirements and recommendations for an automotive functional safety lifecycle, practical guidance on how to handle these safety activities and safety artifacts is still lacking. This paper provides an overview of a semi-formal safety engineering approach based on SysML for specifying the relevant safety artifacts in the concept phase. Using specific diagram types, different views of the available data can be provided that reflects the specific needs of the stakeholders involved. One objective of this work is to improve the common understanding of the relevant safety aspects during the system design. The approach, which is demonstrated here from the perspective of a Tier1 supplier for an automotive battery system, covers different breakdown levels of a vehicle. The safety workflow presented here supports engineers' efforts to meet the safety standard ISO 26262 in a systematic way.
2015-04-14
Technical Paper
2015-01-0264
Jeya Padmanaban
Abstract This study examined the Consumer Product Safety Commission (CPSC) Death Certificate file to identify frequency and rate of accidental CO poisoning deaths associated with exhaust gases of stationary vehicles in enclosed areas. A comprehensive search was then made to determine whether or not there was an increase in such deaths with the introduction of “smart keys” (available as standard equipment beginning in 2004). For 2000-2011 CY, the CPSC file contained 4,760 death certificate records for ICD-10 code X47 (accidental poisoning by exposure to other gases and vapors). The manual review of narratives for these records covered 2004-2011 and found 1,553 CO poisoning deaths associated with vehicle exhaust, including 748 for enclosed areas. For these 748 incidents, information on victim and location was then identified, and an exhaustive effort was undertaken to determine whether the vehicles involved were equipped with rotary or smart keys.
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.
2015-04-14
Journal Article
2015-01-0285
Ehsan Moradi-Pari, S M Osman Gani, Yaser P. Fallah, Mohammad Naserian, Allan Lewis
Abstract Cooperative collision warning (CCW) systems use communication networks as a main component for creating situational awareness and eventually hazard detection. Simulation and analysis of such systems are generally more complicated due to the system being composed of components from very different domains of communication and vehicle safety. These components are inherently developed and modeled in different domains, as their basic operations are usually defined and engineered by researchers from different disciplines. Creating a simulation tool for CCW systems requires combining simulation models that are developed using different methodologies. As a result, a unified tool for study of such systems is not readily available. In this paper, we describe a co-simulation tool that models both components of communication and hazard prediction in one framework.
2015-04-14
Technical Paper
2015-01-0369
Rupesh Sonu Kakade
Abstract In addition to the thermal comfort of the vehicle occupants, their safety by ensuring adequate visibility is an objective of the automotive climate control system. An integrated dew point and glass temperature sensor is widely used among several other technologies to detect risk of fog formation on the cabin side (or inner) surface of the windshield. The erroneous information from a sensor such as the measurement lag can cause imperfect visibility due to the delayed response of the climate control system. Also the high value, low cost vehicles may not have this sensor due to its high cost. A differential equation based model of the cabin air humidity is proposed to calculate in real-time specific humidity of the passenger compartment air. The specific humidity is used along with the windshield surface temperature to determine relative humidity of air and therefore, the risk of fog formation on the interior surface of a windshield.
2015-04-14
Journal Article
2015-01-0449
Libo Cao, Kai Zhang, Xin Lv, Lingbo Yan
Abstract The public Hybrid III family finite element models have been used in simulation of automotive safety research widely. The validity of an ATD finite element model is largely dependent on the accuracy of model structure and accurate material property parameters especially for the soft material. For Hybrid III 50th percentile male dummy model, the femur load is a vital parameter for evaluating the injury risks of lower limbs, so the importance of accuracy of knee subcomponent model is obvious. The objective of this work was to evaluate the accuracy of knee subcomponent model and improve the validity of it. Comparisons between knee physical model and knee finite element model were conducted for both structure and property of material. The inaccuracy of structure and the material model of the published model were observed.
2015-04-14
Technical Paper
2015-01-0499
Nagarjun Jawahar, Sangamitra Manoharan, Harish Chandran
Abstract Material energy and cost minimization has been the need of the hour off late. The work aims at designing a micro gripping device which has suitable application in bio medical industry; specifically surgical operation of comminuted fracture using CAE software. Being a combination of an inverter and a clip, the ability of the compliant mechanism to be used as a gripper as well as positioner constitutes its rare versatility. The compliant mechanisms are single-piece structures, having no backlash as in case of rigid-body, jointed mechanisms and comparatively cheaper to manufacture. Designed in MATLAB R2008a using the concept of topological optimization, modeled in AutoCAD Mechanical 2011 and analyzed in ANSYS Workbench 13.0; the mechanism is initially designed with a geometrical advantage of 2. The MATLAB code which is an improvement of the 99 line code written by O.
2015-04-14
Technical Paper
2015-01-0502
Zhicheng Xu, Gangfeng Tan, Xingzhi Sun, Yongqiang Ge, Min Hua, Haobo Xu
Abstract For the thin ice on the road in winter, the traditional road deicing vehicle relies on mechanical and chemical methods for melting ice, which is inclined to damage the pavement and has insidious influence on environment. The thermal deicing vehicle has been adopted in recent years. Although the deicing method is available, the deicing efficiency is unacceptable while the energy consumption is huge. The study adopts the new idea of “bottom-to-top” for melting the intersection area between the road surface and the bottom ice layer by the microwave heating firstly and then cleaning them out using high pres. vapor cutting so as to save the cost of energy and enhance the traffic safety. First of all, the mathematical model of the melting process of the intersection of the pavement and the ice layer was established according to the microwave heating characteristics.
2015-04-14
Technical Paper
2015-01-0310
R Danymol, Krishnan Kutty
Abstract Camera sensors that are made of silicon photodiodes and used in ordinary digital cameras are sensitive to visible as well as Near-Infrared (NIR) wavelength. However, since the human vision is sensitive only in the visible region, a hot mirror/infrared blocking filter is used in cameras. Certain complimentary attributes of NIR data are, therefore, lost in this process of image acquisition. However, RGB and NIR images are captured entirely in two different spectra/wavelengths; thus they retain different information. Since NIR and RGB images compromise complimentary information, we believe that this can be exploited for extracting better features, localization of objects of interest and in multi-modal fusion. In this paper, an attempt is made to estimate the NIR image from a given optical image. Using a normal optical camera and based on the compressed sensing framework, the NIR data estimation is formulated as an image recovery problem.
2015-04-14
Technical Paper
2015-01-0312
Jiji Gangadharan, Shanmugaraj Mani, Krishnan Kutty
Abstract Advanced Driver Assistance System (ADAS) in combination with other active safety features like air bags etc. is gaining popularity. Vision based ADAS systems perform well under ideal lighting, illumination and environmental conditions. However, with change in illumination and other lighting related factors, the effectiveness of vision based ADAS systems tend to deteriorate. Under conditions of low light, it is therefore important to develop techniques that would offset the effects of low illumination and generate an image that appears as if it were taken under ideal lighting conditions. To accomplish this, we have developed a method, that uses local color statistics from the host image with low illumination, and enhance the same using an adaptive color transfer mechanism.
2015-04-14
Technical Paper
2015-01-0311
Reecha Yadav, Vinuchackravarthy Senthamilarasu, Krishnan Kutty, Vinay Vaidya, Sunita Ugale
Abstract In view of the continuous efforts by the automotive fraternity, for achieving traffic safety, detecting pedestrians from image/video has become an extensively researched topic in recent times. The task of detecting pedestrians in the urban traffic scene is complicated by the considerations involving pedestrian figure size, articulation, fast dynamics, background clutter, etc. A number of methods using different sensor technologies have been proposed in the past for the problem of pedestrian detection. To limit the scope, this paper reviews the techniques involved in day-time detection of pedestrians, with emphasis on the methods making use of a monocular visible-spectrum sensor. The paper achieves its objective by discussing the basic framework involved in detecting a pedestrian, while elaborating the requisites and the existing methodologies for implementing each stage of the basic framework.
2015-04-14
Technical Paper
2015-01-0307
Hongfeng Wang, Lei He, Qianfei Liu, Changfu Zong
Abstract Nowadays active collision avoidance has become a major focus of research, and a variety of detection and tracking methods of obstacles in front of host vehicle have been applied to it. In this paper, laser radars are chosen as sensors to obtain relevant information, after which an algorithm used to detect and track vehicles in front is provided. The algorithm determines radar's ROI (Region of Interest), then uses a laser radar to scan the 2D space so as to obtain the information of the position and the distance of the targets which could be determined as obstacles. The information obtained will be filtered and then be transformed into cartesian coordinates, after that the coordinate point will be clustered so that the profile of the targets can be determined. A threshold will be set to judge whether the targets are obstacles or not. Last Kalman filter will be used for target tracking. To verify the presented algorithm, related experiments have been designed and carried out.
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