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Viewing 151 to 180 of 16143
2015-04-14
Technical Paper
2015-01-1435
Jeffrey Wirth, Enrique Bonugli, Mark Freund
Google Earth is a map and geographical information application created and maintained by Google Corporation. The program displays maps of the Earth using images obtained from available satellite imagery, aerial photography and geographic information systems (GIS) 3D globe. Google Earth has become a tool often used by accident reconstructionist to create scene drawings and obtain dimensional information. In some cases, a reconstructionist will not be able to inspect the scene of the crash due to various circumstances. For example, a reconstruction may commence after the roadway on which the accident occurred has been modified. In other cases, the time and expense required to physically inspect the incident site is not justifiable. In these instances, a reconstructionist may have to rely on Google Earth imagery for dimensional information about the site. The accuracy of the Google Earth is not officially documented.
2015-04-14
Technical Paper
2015-01-1434
Gary A. Davis
Martinez and Schlueter (1996) described a method for reconstructing tripped rollover crashes, where the vehicle’s path is divided into pre-trip, trip, and post-trip phases. Brach and Brach (2011) also describe this method and noted that the trajectory segmentation method for the pre-trip phase needs further validation. When the rolling vehicle leaves a measurable yaw mark at the start of its pre-trip phase it might be possible to partially validate the roll model by comparing its initial speed estimates to those obtained from the critical speed method. This paper describes a Bayesian reconstruction of two such cases. For the first, the 95 percent confidence interval via the critical rate method was (64 mph, 73 mph) while the 95 percent confidence interval via the rollover model was (65 mph, 80 mph). For the second case the confidence intervals were (78 mph, 85 mh) and (79 mph, 92 mph), respectively.
2015-04-14
Technical Paper
2015-01-1330
Yoshiyuki Tosa, Hiroyuki Mae
The passenger airbag hits the windshield when it deploys, causing the impulse force to the windshield. To protect passengers, we must adequately support the airbag between the windshield and the instrument panel. We must not fracture the windshield deploying the airbag. We reviewed methods to simulate the stress on the windshield during deployment. This research predicts the dynamic strain on the windshield from deploying the airbag without vehicle tests. Deployment is fast enough to ignore spatial difference in the patterns of the pressure time histories. In this study, the prediction method consists of a deployment test and an FE simulation. The simple deployment test measures the dynamic pressure distribution between the airbag and the flat panel simulating the windshield.
2015-04-14
Technical Paper
2015-01-1341
Hisaki Sugaya, Yoshiyuki Tosa, Kazuo Imura, Hiroyuki Mae
When airbags deploy they break a plastic tear part of the instrument panel. Timing and the tear fracture process change the airbag’s deployment behavior. The tear fracture process is dependent on the plastic’s temperature. We developed a tear fracture simulation . Because the tear line is composed of 1mm width and 0.5mm-3.0mm flute thickness, simulating the tear fracture process is difficult, even using two models: airbag deployment, and plastic fracture. Thickness determines the tear fracture. The strain distribution of its parts should be predicted accurately. The tear fracture using solid mesh, which is 0.1mm mesh pitch, is predictable. Although it is a very complicated model and has a high computation cost, it is not applicable to the mass production development. We increase the accuracy of the tear fracture process prediction using the shell mesh, which is applicable to the mass production development.
2015-04-14
Technical Paper
2015-01-1464
Qiang Chen, Miao Lin, Bing Dai, Jiguang Chen
The objective of this work was to describe typical accident scenarios for pedestrian accidents in China. The accident analysis aims to develop test procedures for assessing Autonomous Emergency Braking (AEB) systems. Beyond that, this study was also with the goal of estimating the effectiveness of potential reduction of fatally and severely injured pedestrians by AEB systems.Based on statistics, more than 25% of traffic fatalities were pedestrians in China. Autonomous Emergency Braking (AEB) systems are already penetrating the vehicle market and are designed to offer protection against the occurrence and severity of collisions. However there is a need to evaluate the systems and their effectiveness. Test methods for such active safety systems are being developed and will be implemented in NCAP tests in the near future, e.g. 2016 in Euro-NCAP, and most probably in 2018 C-NCAP tests (still in consulting phase).
2015-04-14
Technical Paper
2015-01-0571
Andreas Teibinger, Christian Mayer, Ernö Dux, Gian Antonio D’Addetta, Peter Luttenberger, Jac Wismans, Rémy Willinger
In the next 20 years the number of small and light-weight full electric vehicles will substantially increase especially in urban areas. These Small Electric Vehicles (SEVs) show distinctive design differences compared to traditional vehicles (e.g. vertical windscreens, outstanding wheels). Thus the consequences of impacts of SEVs with vulnerable road users (VRUs) and other (mostly heavier) vehicles will be different from traditional collisions. These fundamental changes are not adequately addressed by current vehicle safety evaluation methods and regulations. Furthermore, no assessment concerning vehicle safety is defined for vehicles within European L7e class currently. Therefore the final objective of the EC co-financed project SafeEV is the development of a clear and practicable guideline for virtual testing of small electric vehicles. As a basis a virtual tool chain has to be defined for the realization of a guideline of virtual certification.
2015-04-14
Technical Paper
2015-01-0575
SongAn Zhang, Qing Zhou, Yong Xia
Small lightweight electric vehicle (SLEV) is an approach for compensating low energy density of the current battery. However, small lightweight vehicle presents technical challenges to crash safety design. One issue is that mass of battery pack and occupants is a significant portion of vehicle’s total weight, and therefore, the mass distribution has great influence on crash response. Using finite element modeling, this paper presents a parametric analysis. For this research purpose, we first built LS-DYNA model of SLEV with curb weight of 600 kg , which is a two-seater. The model has no complex components, but it can provide reasonable crash pulses under full-frontal rigid barrier crash loading and offset deformable barrier (ODB) crash loading.
2015-04-14
Technical Paper
2015-01-0307
Hongfeng Wang, Lei He, Qianfei Liu, Changfu Zong
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. This paper chooses laser radars as sensors to obtain relevant information, and then presents a algorithm to detect and track vehicles in front. The algorithm determine 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 obstacles can be determined. A threshold will be set to judge whether the obstacles are vehicles or not. Last Kalman filter will be used for target tracking. To verify the presented algorithm, related experiments have been designed and carried out.
2015-04-14
Technical Paper
2015-01-1406
Mikael Ljung Aust, Lotta Jakobsson, Magdalena Lindman, Erik Coelingh
This paper presents and discusses the continuous evolution of the developments in the area of collision avoidance systems. Collision avoidance systems have been on the market for a decade, and the development has been rapid. Starting with forward collision warning with brake support targeting vehicles moving in the same direction in front of the car, collision avoidance systems 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. The development up to date, along with future challenges, are described and discussed according to challenge areas; e.g. detection, decision strategy and intervention strategy. Also, ways of assessing system effects are discussed. Numerous studies have been made predicting the effect of different systems, and the real world effects of these systems have been shown to be significant.
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 technology can effectively improve vehicle safety. Most of them predict vehicle crashes using radar or video, but it can’t be applied extensively currently due to high cost. Another collision forecasting method is more economic which base on driver behavior and vehicle status, such as acceleration, angular velocity of the brake pedal and so on. But acceleration and angular velocity of the brake pedal will change with drive and vehicle change. In order to study the effect of different drives and vehicle types on 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 test content.
2015-04-14
Technical Paper
2015-01-1404
Arda Kurt, Güchan Özbilgin, Keith A. Redmill, Rini Sherony, Ümit Özgüner
In this paper, a series of design, development, and implementation details for testing and evaluation of Lane Departure Warning and Prevention systems are being discussed. The approach taken to generate a set of repeatable and relevant test scenarios and to formulate the test procedures to ensure the fidelity of the collected data includes initial statistical analysis of applicable statistics; growth and probabilistic pruning of a test matrix; simulation studies to support procedure design; and vehicle instrumentation for data collection. The success of this comprehensive approach strongly suggests that the steps illustrated in this paper can serve as guidelines towards a more general class of vehicular safety and advanced driver assistance systems evaluation.
2015-04-14
Technical Paper
2015-01-1410
Shotaro Odate, Kazuhiro Daido, Yosuke Mizutani
According to the National Automotive Sampling System (NASS) Crashworthiness Data System (CDS), which is a North American automobile accident database, collision events referred to as multiple-collision accidents, in which multiple collisions occur during travel, account for 55% of all accidents. In addition, multiple-collision accidents in which collision events following the first collision event are more severe than the first event account for 20% of all accidents. In a first collision, the system had simultaneously operated to restrain and protect the vehicle occupant. If the multiple-collision accidents occurs, because the system for restraining and protecting vehicle occupants will have already deployed, the performance of the system can be limited from subsequent collisions.
2015-04-14
Technical Paper
2015-01-1409
Joseph Yoon, Kajetan Kietlinski, Freerk Bosma, Martin Tijssens
These days, we begin to see more vehicles equipped with new active safety systems such as radar/camera system and collision imminent braking (CIB) system, etc. The active safety systems are designed and introduced as a safety system in order to help avoid crashes or mitigate injuries when crashes are unavoidable. However, through some internal study conducted at TASS International, we discovered that there may be a potential risk of increased injuries to the occupant when the activation of the active safety systems is not coordinated with that of the passive safety system. For example, when CIB is activated, it puts the occupant out of position closer to the deploying airbag therefore potentially increase injury risks. This risk is believed to be more severe if the occupant is not belted.
2015-04-14
Technical Paper
2015-01-1411
Caroline Crump, David Cades, Robert Rauschenberger, Emily Hildebrand, Jeremy Schwark, Brandon Barakat, Douglas Young
Advanced Driver Assistive System technologies are currently available in many passenger vehicles that provide safety benefits and will ultimately lead to autonomous, “self-driving” vehicles. One technology that has the potential for having substantial safety benefits is the forward collision warning and mitigation (FCWM) system, which is designed to (1) warn drivers of imminent front-end collisions, (2) potentiate driver braking responses, and (3) have the ability to apply the vehicle’s brake autonomously to slow, or, in some cases, stop the vehicle prior to a forward collision. Although the proliferation of such technologies can, in many ways, mitigate the necessity of a timely braking response by a driver in an emergency situation, how this system affects a driver’s overall ability to safely, efficiently, and comfortably operate a motor vehicle remains unclear.
2015-04-14
Technical Paper
2015-01-1414
Jitendra Shah, Mohamed Benmimoun
In the framework of large scale project interactIVe co-funded by the European Commission Ford has developed an active safety system for the supported and autonomous avoidance of rear end collisions by intervention of braking and steering systems. This paper focuses on the assessment of threat perceived by drivers in collision avoidance situation. The decision making related to the initiation of the interventions by driver is crucial to understand how much threat is the driver can hold. The study has helped to understand how driver feels a threat arising from environment. It is a step towards autonomous driving where the system interventions have to be initiated as early as possible in order to avoid the collision and avoid unstable vehicle dynamics situations. In parallel the reaction has to be delayed long enough until it is likely that the driver will no longer intervene or respectively he is no longer able to intervene. For this reason an experiment is conducted with 26 subjects.
2015-04-14
Technical Paper
2015-01-1413
Louis Tijerina, Michael Blommer, Reates Curry, Radhakrishnan Swaminathan, Dev Kochhar, Walter Talamonti
Objective: Investigate statistical effects of repeated measures design in FCW (warning vs. no-warning ) evaluation Background: Repeated measures designs are often used in FCW testing despite concerns that 1st exposure creates expectancy effects which may dilute or bias outcomes Method: 32 participants were divided into groups of 8 for an AA, BB, AB, BA design (A= no warning; B=FCW). They drove in a high-fidelity, motion-base simulator with a visual distraction task. After some 25 minutes of driving a simulated nighttime rural highway, a high-intensity forward collision threat arose during the distraction task. Response time was analyzed. Results: There was evidence of differential carryover and significant Period 1 vs. 2 effects which dilute the magnitude of difference between FCW and no warning relative to 1st exposure only. Also there was a trend toward slower response with no-warning after FCW exposure as first exposure than after no-warning as first exposure.
2015-04-14
Technical Paper
2015-01-1451
Anand Sai Gudlur, Theresa Atkinson
ABSTRACT The current study examined field data in order to document injury rates, injured body regions, and injury sources for persons seated in the second row of passenger vehicles. It was also intended to identify whether these varied with respect to age and restraint use in vehicles manufactured in recent years.Data from the 2007-2012 National Automotive Sampling System (NASS/CDS) was used to describe occupants seated in the second row of vehicles in frontal crashes. Injury plots, comparison of means and logistic regression analysis were used to identify factors associated with increased risk of injury. Restraint use reduced the risk of AIS ≥ 2 injury from approximately 1.8% to 5.8% overall. Seventy nine percent of the occupants in the weighted data set used either a lap and shoulder belt or child restraint system. The most frequently indicated injury source for persons with a MAIS ≥ 2 was “seat, back support”, across restraint conditions and for all but the youngest occupants.
2015-04-14
Technical Paper
2015-01-1460
Massoud Tavakoli, Janet Brelin-Fornari
This study was conducted to explore the effect of various combinations of seatbelt-related safety components on the adult rear passenger involved in a frontal collision. The study was conducted on a 50th male and a 5th female Hybrid III ATD in the rear seat of a mid-sized sedan. Each ATD was seated in an outboard position with 3-point continuous lap-shoulder belts. On these belts were combinations of pretensioners and load limiters. Since the main objective of the test series was to cross-compare the seatbelt configurations, front seats were not included in the buck to avoid the possibility of contact with the front seat, hence avoiding such uncontrollable variables. Nevertheless, there was a short barrier devised to act as a foot-stop for both ATDs. A design of experiment (DOE) was constructed as a full factorial with and without a pretensioner and three types of load limiters. Each ATD was tested with a progressive load limiter (PLL1).
2015-04-14
Technical Paper
2015-01-1458
Jia Hu
The driver and front row occupant safety is always the focus in the development of crash regulations and New Car Assessment Program (NCAP). However in recent years, rear row occupant safety is also being paid attention to widely. The rear row occupant safety is being included in the NCAP of different countries. JNCAP began to assess the rear row occupant safety in 2009. C-NCAP started to assess the rear row occupant safety from July, 2012. Euro NCAP is also being updated. The frontal 50-kph full rigid barrier impact test will be included in Euro NCAP from 2015 and two Hybrid III 5th percentile dummies will be positioned in both the driver seat and the rear seat. For the rear row occupants wearing seatbelts, thoracic injuries from the seatbelt are by far the dominant injury type. For unbelted rear row occupants, the extremities and head are frequently injured by the B pillar, the front seat and other interior components.
2015-04-14
Technical Paper
2015-01-1456
Mani Ayyakannu, Latha Subbiah, Mohammed Syed
Abstract: Knee Bolster requirements have changed substantially in recent years due to expanded safety requirements. A knee bolster assembly has been evolved to meet this matrix of requirements while being extremely lightweight (as low as 2 lbs), low in cost and easily tunable to work in various car/truck programs. The energy absorber is the primary component of this assembly and allows for a range of occupant sizes and weights to be protected( from a 50 Kg/5ft 5th percentile female to a 100 Kg/6ft 2 in 95th percentile male occupants). The evolution of this knee bolster assembly design is described using crush analysis, component testing to validate the crush analysis, instrument panel assembly level analysis with occupant models and sled tests. Steel and aluminum versions of this knee bolster are compared - in terms of weight, cost, design tunability for various crash conditions, structural stiffness etc.
2015-04-14
Technical Paper
2015-01-1459
Lotta Jakobsson, Magnus Björklund, Anders Axelson
Vertical accelerations can cause thoracic and lumbar spine injuries to a car occupant. Representative crashes potentially causing occupant vertical accelerations include; rollover events or free flying events when the car lands on its wheels, and run off road events when the car goes into the ditch and collides with an embankment from a crossing road. The spinal tolerances are dependent on occupant posture at time of impact which is an important factor with respect to limit of tolerances. Up to date, there is no standardized test method evaluating this occupant loading mechanism. The aim of this study was to develop test methods addressing vertical acceleration for car occupants and to evaluate countermeasures reducing the vertical loadings. Based on real world run off road crash investigations, representative test track methods were developed; including free flight before landing on the wheels and traveling in ditch impacting an embankment.
2015-04-14
Technical Paper
2015-01-1453
Jingwen Hu, Kurt Fischer, Paul Lange, Angelo Adler
Recent field data analyses have shown that front seats may provide better occupant protection than rear seats in newer vehicle models. The design of vehicle rear-seat compartment for protecting occupants is more challenging than front-seat because of the wide range of occupant ages and sizes that must be accommodated and protected. Furthermore, the increased demand for vehicle fuel economy will result in smaller rear-seat compartment and higher crash pulses, both of which will need further efforts to better protect rear-seat occupants. Therefore, the objective of this study is to use sled tests to quantify the effects of crash pulse, impact angle, occupant size, and front seat location on rear seat occupant protection. In this study, a sled buck representing a current compact vehicle was developed based on a HYGE system.
2015-04-14
Technical Paper
2015-01-1457
Aditya Belwadi, Richard Hanna, Audrey Eagle, Daniel Martinez, Julie Kleinert, Eric Dahle
Automotive interior design optimization must balance the design of the vehicle seat and occupant space for safety, comfort and aesthetics with the accommodation of add-on restraint products such as child restraint systems (CRS). It is important to understand the breadth of CRS dimensions so that this balance can be successfully negotiated. Previously this was addressed with the advent of advanced air bag systems, when emphasis was placed on the design and development of surrogate child restraints, which were used, in developing and testing occupant sensing and classification systems. CRS design is constantly changing. In particular, the introduction of side impact protection for CRS as well as emphasis on ease of CRS installation has likely changed key design points of any child restraints. This ever-changing target puts pressure on the vehicle manufacturers to keep their vehicle seats and occupant space compatible.
2015-04-14
Technical Paper
2015-01-1455
Kenshi Torikai, Hitoshi Higuchi, Kazuhiro Seki
Airbags help mitigate direct hits. The passenger airbag has a vent structure discharging the internal gas such that a suitable airbag reaction force is obtained. Since the conventional vent structure is always open, the reaction force of such an airbag tends to fall when the contact timing (CT) is long. What prevents this drop in the airbag reaction force is a structure which closes the vent hole until contact to maintain the internal pressure and opens the vent hole after contact. However, variable vent structures are typically complicated and difficult to control due to the lid of the vent hole and a strap to pull the lid. We researched a simplified variable vent structure, investigating a “slit type” vent structure to reduce the complexity of conventional variable vent structures.
2015-04-14
Technical Paper
2015-01-1462
Seung Jun Yang
Euro-Ncap committee has been adopted overall impact star-grade system after 2009 and strengthening pedestrian protection cut-off score to obtain best impact-star grade until 2016. It is very difficult target to pass enhanced pedestrian cut-off score due to previous method. In this paper, I studied where is pedestrian weak area and why pedestrian injury is so high at that area based on our test result. I compared long-hood, 3 corner pop-up hood and pedestrian air-bag system. Finlly I suggest 3-corner rear-ward hood pop-up system is best method to meet our Impact new target in considering pedestrian protection ability, cost &weight.
2015-04-14
Technical Paper
2015-01-1461
Dietmar Otte
During most pedestrian-vehicle crashes the car front impacts the pedestrian and the whole body wraps around the front shape of the car. Meanwhile the windscreen is tested in NCAP conditions. The severity of injuries is influenced by car impact speed; type of vehicle; stiffness and shape of the vehicle; nature of the front (such as the bumper height, bonnet height and length, windscreen frame); age and height of the pedestrian; and standing position of the pedestrian relative to the vehicle front. The socalled Wrap Around Distance WAD is one of important measurement for the assessment of protection. For the study accidents with pedestrians and bicyclists are used for the analysis, how good is the WAD for injury prediction. GIDAS (German In-Depth-Accident-Study) collects accidents as representative sample of the German accident situation based on in-depth-investigation.
2015-04-14
Technical Paper
2015-01-1469
Yan Wang, Taewung Kim, Yibing Li, Jeff Crandall
The characteristic of neck plays an important role on the kinematics and injury of pedestrian’s neck and head during the impact with vehicle, and the accuracy of the mathematical model affects the analysis results directly. A new mathematical pedestrian model has been developed in University of Virginia (UVA), which combines the advantages of both TNO facet occupant model and the lower extremity with more accuracy of biomechanical characteristics. So in this new pedestrian model, the occupant’s facet neck model developed by TNO is used to evaluate the pedestrian’s kinematics and dynamic response. Since the neck is special developed for occupants, the mechanical characteristics for lateral impact may not as good as that of frontal impact.
2015-04-14
Technical Paper
2015-01-1471
Hiroyuki Asanuma, Yukou Takahashi
Investigation with a pedestrian dummy develops further understanding of real-world pedestrian accidents. Investigating injuries to the pedestrian lower body, biofidelity of the thigh, leg, and pelvis of a pedestrian dummy were improved. Plastic solid shafts, covered by flesh jackets were the thigh and the leg from earlier studies. Biofidelity has been evaluated by means of 3-point bending; however, the inertial properties of these parts were adjusted to mimic a human. Biofidelity of the dummy’s pelvis was evaluated in lateral compression of an isolated pelvis. The dummy tests were performed in only quasi-static condition. This study improves and validates the lower limb and the pelvis of the pedestrian dummy, enhancing injury assessment. These parts were subjected to latero-medial 3-point bending at the deflection rate of 1.5 m/s.
2015-04-14
Technical Paper
2015-01-1465
Sho Nikaido, Shota Wada, Yasuhiro Matsui, Shoko Oikawa, Toshiya Hirose
1. Background and purpose There are various contributing factors to accidents of bicycles, it is considered that cyclists often do not observe the traffic regulation that requires cyclists to stop before a stop line at an intersection. As a countermeasure to this type of accident, cycling assist systems that activate a warning system for cyclists have been researched and developed. This assist system warns the cyclist about the danger of a collision. Such an assist system needs to provide a warning with appropriate timing. It is necessary to clarify cycling characteristics in developing a countermeasure for traffic accidents at an intersection without signals. The findings of this study can be used for the future construction of an assist system that will encourage cyclists to observe traffic regulations.
2015-04-14
Technical Paper
2015-01-1466
Dietmar Otte, Thorsten Facius, Birgit Wiese
The overall number of severely injured participants and fatalities in road traffic accidents has decreased enormously in the last decades. These casualties in the group of riders of motorcycles in traffic accidents have only decreased in a smaller percentage. The aim of this study is to analyze the accident situation of motorcycles with severely injured and killed riders of motorcycles with cubic capacity > 125 cm³ in Germany, to identify the characteristics in injury mechanisms and accident constellations and to find countermeasures to be suggested. The accident data of 1,498 drivers of motorcycles involved in traffic accidents were analyzed, collected by a scientific research team of GIDAS (German In-Depth Accident Study) in the area of Hannover and Dresden within the years 2000 up to 2013. For finding such characteristic, two samples are selected and compared, first the group of MAIS 3+ injured cyclists (n= 245) and second the group of MAIS 1 and 2 injured cyclists (n= 1253).
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