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2015-04-14
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Active Safety and Driver assistance systems are gaining importance as many passive safety systems have already been found to have yielded significant safety benefits that are possible from the deployment of those systems in the fleet. Similar success will much depend upon how fast these systems proliferate the entire passenger vehicle fleet. It will also depend on the deployment strategies used by the industry and the government as well as consumer acceptance and market demand for these systems. Additionally, opportunities exist to use the information gained from the various onboard sensors and vision systems in active safety systems for improving the effectiveness of today’s passive safety systems such as seat belts, airbags, and post-crash safety systems even further by the integration of active and passive safety systems.
2015-04-14
Technical Paper
2015-01-0575
SongAn Zhang, Qing Zhou, Yong Xia
Abstract 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. This paper presents a parametric analysis using finite element modeling. We first build LS-DYNA model of a two-seater SLEV with curb weight of 600 kg. The model has no complex components and can provide reasonable crash pulses under full frontal rigid barrier crash loading and offset deformable barrier (ODB) crash loading.
2015-04-14
Technical Paper
2015-01-0564
Sung Wook Moon, Byunghyun Kang, Jaeyoung Lim, Byoung-Ho Choi
Abstract In a car accident which is involving pedestrians, head injuries occur very frequently as the head of the pedestrian hits the windshield. The head injury criterion (HIC) obtained through the windshield impact test is used to evaluate the pedestrian injury, and car manufacturers are trying to meet the criterion by changing the design and/or materials.. However, there are some difficulties in the windshield impact test, e.g. a large scatter of the test data or windshield shape-dependent property of the test. These problems make it very difficult to obtain the meaningful results from single test and thus, tests should be executed several times. In this study, a lab-scale windshield impact test was performed using a modified instrumented dart impact (IDI) tester. Tests were carried out by switching test conditions such as the impact speed, the size of the head form and the specimen thickness.
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
Journal Article
2015-01-1426
Drew A. Jurkofsky
Abstract Photogrammetry from images captured by terrestrial cameras and manned aircraft has been used for many years to model objects, create scale diagrams and measure distances for use in traffic accident investigation and reconstruction. Due to increasing capability and availability, Unmanned Aircraft Systems (UAS), including small UAS (SUAS), are becoming a valuable, cost effective tool for collecting aerial images for photogrammetric analysis. The metric accuracy of scale accident scene diagrams created from SUAS imagery has yet to be compared to conventional measurement methods, such as total station and laser measurement systems, which are widely used by public safety officials and private consultants. For this study, two different SUAS were used to collect aerial imagery for photogrammetric processing using PhotoModeler software.
2015-04-14
Technical Paper
2015-01-1435
Jeffrey Wirth, Enrique Bonugli, Mark Freund
Abstract 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 reconstructionists to create site drawings and obtain dimensional information. In some cases, a reconstructionist will not be able to inspect the site 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 Google Earth is not officially documented.
2015-04-14
Technical Paper
2015-01-1434
Gary A. Davis
Abstract Martinez and Schlueter [6] described a three-phase model for reconstructing tripped rollover crashes, where the vehicle's path is divided into pre-trip, trip, and post-trip phases. Brach and Brach [9] also described this model and noted that the trajectory segmentation method for the pre-trip phase needed further validation. When a vehicle leaves a measurable yaw mark at the start of its pre-trip phase it might be possible to compare estimates from the three-phase model to those obtained using the critical speed method, and this paper describes Bayesian reconstruction of two such cases. For the first, the 95 percent confidence interval for the case vehicle's initial speed, estimated using the critical speed method, was (64 mph, 81 mph) while the 95 percent confidence interval via the three-phase model was (66 mph, 79 mph).
2015-04-14
Technical Paper
2015-01-1462
Seung Jun Yang
Abstract Each year, more than 270,000 pedestrians lose their lives on the world's roads. Globally, pedestrians constitute 22% of all road traffic fatalities, and in some countries this proportion is as high as two thirds of all road traffic deaths. Millions of pedestrians are non-fatally injured and some of whom are left with permanent disabilities. These incidents cause much suffering and grief as well as economic hardship. To lower the rate of pedestrian injuries and fatalities, the Euro-Ncap committee adopted an overall impact star-grade system in 2009, making the pedestrian protection cut-off score required to obtain the best impact-star grade more stringent until 2016. It is very difficult to surpass the enhanced pedestrian cut-off score using past methods. In this paper, I determine the hood's worst-performing areas in terms of pedestrian protection by analyzing previous pedestrian test results.
2015-04-14
Technical Paper
2015-01-1471
Hiroyuki Asanuma, Yukou Takahashi
Abstract The evaluation of pedestrian safety performance of vehicles required by regulations and new car assessment programs (NCAPs) have been conducted. However, the behavior of a pedestrian in an actual car-pedestrian accident is complex. In order to investigate injuries to the pedestrian lower body, the biofidelity of the lower limb and the pelvis of a pedestrian dummy called the POLAR II had been improved in past studies to develop a prototype of the next generation dummy called the POLAR III. The biofidelity of the thigh and the leg of the POLAR III prototype has been evaluated by means of 3-point bending. However, the inertial properties of these parts still needed to be adjusted to match those of a human. The biofidelity of the pelvis of the POLAR III prototype has been evaluated in lateral compression. Although the experiment using PMHSs (Post Mortem Human Subjects) was conducted in dynamic condition, the dummy tests were performed only in quasi-static condition.
2015-04-14
Technical Paper
2015-01-1479
Adria Ferrer, Eduard Infantes
Abstract The introduction of the new NHTSA (National Highway Traffic Safety Administration) oblique test configuration presents a new and critical load case that manufacturers are on the way to solving. Towards providing the best tools for passive safety development, this paper presents the work carried out to enable the analysis of the loads transmitted to the barrier in this kind of test. These data enable the identification of the elements of the vehicle that take part in the absorption of energy during the crash and are a valuable tool to improving the safety of vehicles by comparing the loads transmitted to the barrier in oblique tests. To record these data, a load cell wall system located between the deformable barrier and the trolley was installed. To assess the barrier design, one oblique test with the RMDB barrier was carried out. The deformable barrier for the oblique test is instrumented with 9 columns of 3 and 4 load cells with a total of 32 x-axial load cells.
2015-04-14
Technical Paper
2015-01-0130
Julio Rodriguez, Ken Rogich, Philip Pidgeon, Kim Alexander, John R. Wagner
Abstract Driving skills and driving experience develop differently between a civilian and a military service member. Since 2000, the Department of Defense reports that two-thirds of non-related to war fatalities among active duty service members were due to transportation-related incidents. In addition, vehicle crashes are the leading non-related to war cause of both fatalities and serious injuries among active duty Marines. A pilot safe driving program for Marines was jointly developed by the Richard Petty Driving Experience and Clemson University Automotive Safety Research Institute. The pilot program includes four modules based on leading causes of vehicle crashes, and uses classroom and behind the wheel components to improve and reinforce safe driving skills and knowledge. The assessment results of this pilot program conducted with 192 Marines in September 2011 at Camp LeJeune, NC are presented and discussed.
2015-04-14
Technical Paper
2015-01-1486
Craig A. Markusic, Ram Songade
Abstract Simplified Side Impact Finite Element Model (SSM) merged the complex side crash model parameters used in LS-DYNA4; the same sophisticated software employed by finite element (FE)2 analysts, and the user-friendly custom graphical user interface (GUI)1 to allow users having little to no simulation software knowledge the ability to conduct a full vehicle representative crash simulation. Prior to SSM development a literature search was carried to try and identify similar CAE tools for side impact. We did not find any tool that would cater specifically to side impact. During the testing phase, SSM demonstrated that one model analysis run can be completed in fewer than thirty (30) minutes, a radical efficiency increase because previous procedures require several days of effort from a highly skilled FE2 analyst to set up, execute, and analyze.
2015-04-14
Technical Paper
2015-01-1487
Andreas Teibinger, Harald Marbler-Gores, Harald Schluder, Veit Conrad, Hermann Steffan, Josef Schmidauer
Abstract Structural component testing is essential for the development process to have an early knowledge of the real world behaviour of critical structural components in crash load cases. The objective of this work is to show the development for a self-sufficient structural component test bench, which can be used for different side impact crash load cases and can reflect the dynamic behaviour, which current approaches are not able. An existing basic system is used, which includes pneumatic cylinders with a controlled hydraulic brake and was developed for non-structural deformable applications only (mainly occupant assessments). The system is extended with a force-distance control. The method contains the analysis of a whole vehicle FEM simulation to develop a methodology for controlled force transmission with the pneumatic cylinders for a structural component test bench.
2015-04-14
Technical Paper
2015-01-1458
Jia Hu
Abstract A Finite Element (FE) model for analysis of the rear row occupant injury assessment parameters in a frontal crash test was developed by using the LSTC Hybrid III 5th percentile FE dummy model. Three cases were studied using three different rear seatbelt retractor configurations, which were as follows: an ordinary retractor without load limiter or pretensioner (Case 1), a retractor with load limiter only (Case 2), and a retractor with load limiter and pretensioner (Case 3). The simulation results of each of these three cases were compared respectively to the results obtained from two frontal 50-kph full rigid barrier impact tests and one sled test. It turned out that the dummy kinematics and injury assessment parameters of the head, neck, chest, pelvis and femurs were all similar between test and simulation in the three cases. Thus, FE simulation models can be used to predict dummy injury assessment parameters.
2015-04-14
Technical Paper
2015-01-1443
Morteza Seidi, Marzieh Hajiaghamemar, James Ferguson, Vincent Caccese
Abstract Falls in the elderly population is an important concern to individuals and in the healthcare industry. When the head is left unprotected, head impact levels can reach upwards of 500 g (gravitational acceleration), which is a level that can cause serious injury or death. A protective system for a fall injury needs to be designed with specific criteria in mind including energy protection level, thickness, stiffness, and weight among others. The current study quantifies the performance of a protective head gear design for persons prone to falls. The main objective of this paper is to evaluate the injury mitigation of head protection gear made from a patented system of polyurethane honeycomb and dilatant materials. To that end, a twin wire fall system equipped with a drop arm that includes a Hybrid-III head/neck assembly was used. The head was instrumented with an accelerometer array.
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
Journal Article
2015-01-1422
Neal Carter, Nathan A. Rose, David Pentecost
Abstract Several sources report simple equations for calculating the lean angle required for a motorcycle and rider to traverse a curved path at a particular speed. These equations utilize several assumptions that reconstructionists using them should consider. First, they assume that the motorcycle is traveling a steady speed. Second, they assume that the motorcycle and its rider lean to the same lean angle. Finally, they assume that the motorcycle tires have no width, such that the portion of the tires contacting the roadway does not change or move as the motorcycle and rider lean. This study reports physical testing that the authors conducted with motorcycles traversing curved paths to examine the net effect of these assumptions on the accuracy of the basic formulas for motorcycle lean angle. We concluded that the basic lean angle formulas consistently underestimate the lean angle of the motorcycle as it traverses a particular curved path.
2015-04-14
Technical Paper
2015-01-1467
Chinmoy Pal, Tomosaburo Okabe, Kulothungan Vimalathithan, Jeyabharath Manoharan, Munenori Shinada
Abstract Logistic regression analysis for accident cases of NASS-PCDS (National Automotive Sampling System-Pedestrian Crash Data Study) clearly shows that the extent and the degree of pedestrian's lower extremity injury depend on various factors such as the impact speed, the ratio of the pedestrian height to that of the bonnet leading edge (BLE) of the striking vehicle, bumper to knee ratio, bumper lead angle, age of the pedestrian, and posture of the pedestrian at the time of impact. The pedestrian population is divided in 3 groups, equivalent to small-shorter, medium-height and large-taller pedestrian with respect to the “pedestrian to BLE height-ratio” in order to quantify the degree of influence of lower leg injuries in each group. Large adult male finite element model (95th percentile male: 190 cm and 103 kg) was developed by morphing the Japan Automobile Manufacturers Association (JAMA) 50th percentile male.
2015-04-14
Technical Paper
2015-01-1469
Yan Wang, Taewung Kim, Yibing Li, Jeff Crandall
Abstract Multibody human models are widely used to investigate responses of human during an automotive crash. This study aimed to validate a commercially available multibody human body model against response corridors from volunteer tests conducted by Naval BioDynamics Laboratory (NBDL). The neck model consisted of seven vertebral bodies, and two adjacent bodies were connected by three orthogonal linear springs and dampers and three orthogonal rotational springs and dampers. The stiffness and damping characteristics were scaled up or down to improve the biofidelity of the neck model against NBDL volunteer test data because those characteristics were encrypted due to confidentiality. First, sensitivity analysis was performed to find influential scaling factors among the entire set using a design of experiment.
2015-04-14
Technical Paper
2015-01-1419
Raymond M. Brach
Abstract Numerous algebraic formulas and mathematical models exist for the reconstruction of vehicle speed of a vehicle-pedestrian collision using pedestrian throw distance. Unfortunately a common occurrence is that the throw distance is not known because no evidence exists to locate the point of impact. When this is the case almost all formulas and models lose their utility. The model developed by Han and Brach published by SAE in 2001 is an exception because it can reconstruct vehicle speed based on the distance between the rest positions of the vehicle and pedestrian. The Han-Brach model is comprehensive and contains crash parameters such as pedestrian launch angle, height of the center of gravity of the pedestrian at launch, pedestrian-road surface friction, vehicle-road surface friction, road grade angle, etc. Such an approach provides versatility and allows variations of these variables to be taken into account for investigation of uncertainty.
2015-04-14
Journal Article
2015-01-1433
R. Matthew Brach, Raymond M. Brach, Richard A. Mink
This paper presents a reconstruction technique in which nonlinear optimization is used in combination with an impact model to quickly and efficiently find a solution to a given set of parameters and conditions to reconstruct a collision. These parameters and conditions correspond to known or prescribed collision information (generally from the physical evidence) and can be incorporated into the optimized collision reconstruction technique in a variety of ways including as a prescribed value, through the use of a constraint, as part of a quality function, or possibly as a combination of these means. This reconstruction technique provides a proper, effective, and efficient means to incorporate data collected by Event Data Recorders (EDR) into a crash reconstruction. The technique is presented in this paper using the Planar Impact Mechanics (PIM) collision model in combination with the Solver utility in Microsoft Excel.
2015-04-14
Technical Paper
2015-01-1439
Toshiyuki Yanaoka, Yasuhiro Dokko, Yukou Takahashi
Abstract The high frequency of fatal head injuries is one of the important issues in traffic safety, and Traumatic Brain Injuries (TBIs) without skull fracture account for approximately half of them in both occupant and pedestrian crashes. In order to evaluate vehicle safety performance for TBIs in these crashes using anthropomorphic test dummies (ATDs), a comprehensive injury criterion calculated from the rotational rigid motion of the head is required. While many studies have been conducted to investigate such an injury criterion with a focus on diffuse brain injuries in occupant crashes, there have been only a limited number of studies focusing on pedestrian impacts. The objective of this study is to develop a comprehensive injury criterion based on the rotational rigid body motion of the head suitable for both occupant and pedestrian crashes.
2015-04-14
Technical Paper
2015-01-1460
Massoud Tavakoli, Janet Brelin-Fornari
Abstract This study was conducted to explore the effect of various combinations of seatbelt-related safety components (namely, retractor pretensioners and load limiting retractors) 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 this test series was to cross-compare the seatbelt configurations, front seats were not included in the buck in order to avoid uncontrollable variables that would have affected the comparison study if the possibility of contact with the front seat were allowed. Nevertheless, there was a short barrier devised to act as a foot-stop for both ATDs.
2015-04-14
Technical Paper
2015-01-1465
Sho Nikaido, Shota Wada, Yasuhiro Matsui, Shoko Oikawa, Toshiya Hirose
Abstract Although traffic accidents in Japan involving bicycles have been decreasing yearly, more than 120,000 per year still occur. Few data exist regarding the mechanisms underlying bicycle accidents occurring at intersections. Such dangerous situations form the backdrop of the warning and automatic braking systems being developed for motor vehicles. By clarifying cyclist behavioral characteristics at crucial times, it may be possible to introduce a similar warning system for cyclists as a countermeasure to reduce accidents. The objective of this study is to clarify the mechanism of accidents involving bicycles and to obtain useful data for the development of a warning system for cyclists. A video camera and software investigated and analyzed cyclists' speed and trajectory at an intersection where many accidents occur. Cyclists entering the intersection from one direction were recorded.
2015-04-14
Technical Paper
2015-01-1466
Dietmar Otte, Thorsten Facius, Birgit Wiese
Abstract The overall number of severely injured participants and fatalities in road traffic accidents has decreased enormously during the last decades especially in Europe, but casualties in the group of riders of motorcycles have only decreased in a smaller percentage. In countries of Asia the numbers of motorcycle casualties are increasing regarding the popularity of motorcycle riding. The aim of this study is to analyze the current accident situation of motorcycles in Germany 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 to find countermeasures to be suggested for worldwide accident avoidance and injury reduction. The study was carried out on the basis of accident data of 1,493 drivers of motorcycles involved in traffic accidents in Germany.
2015-04-14
Technical Paper
2015-01-1461
Dietmar Otte
Abstract During most pedestrian-vehicle crashes the car front impacts the pedestrian and the whole body wraps around the front shape of the car. This influences the head impact on the vehicle. Meanwhile the windscreen is a major impact point and 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 body height of the pedestrian; and standing position of the pedestrian relative to the vehicle front. The so called Wrap Around Distance WAD is one of the important measurements for the assessment of protection of pedestrians and of bicyclists as well because the kinematic of bicyclists is similar to that of pedestrians. For this study accidents of GIDAS were used to identify the importance of WAD for the resulting head injury severity of pedestrians and bicyclists.
2015-04-14
Technical Paper
2015-01-1437
Tony R. Laituri, Raed E. El-Jawahri, Scott Henry, Kaye Sullivan
Abstract In the present study, various risk curves for moderate-to-fatal head injury (AIS2+) were theoretically assessed by comparing model-based injury rates with field-based injury rates. This was accomplished by applying the risk curves in corresponding field models. The resulting injury rates were considered from two perspectives: aggregate (0-56 kph events) and point-estimate (higher-speed, barrier-like events). Four risk curves were studied: a HIC15-based curve from Mertz et al. (1997), a BRIC-based curve from Takhounts et al. (2011), a BrIC-based curve from Takhounts et al. (2013) and a Concussion-Correlate-based curve from Rowson et al. (2013). The field modeling pertained to adult drivers in 11-1 o'clock, towaway, full-engagement frontal crashes in the National Automotive Sampling System (NASS, calendar years = 1993-2012), and the model-year range of the passenger vehicles was 1985-2010.
2015-04-14
Journal Article
2015-01-1470
Takahiro Isshiki, Atsuhiro Konosu, Yukou Takahashi
Abstract Current legform impact test methods using the FlexPLI have been developed to protect pedestrians from lower limb injuries in collisions with low-bumper vehicles. For this type of vehicles, the influence of the upper body on the bending load generated in the lower limb is compensated by setting the impact height of the FlexPLI 50 mm above that of pedestrians. However, neither the effectiveness of the compensation method of the FlexPLI nor the influence of the upper body on the bending load generated in the lower limb of a pedestrian has been clarified with high-bumper vehicles. In this study, therefore, two computer simulation analyses were conducted in order to analyze: (1) The influence of the upper body on the bending load generated in the lower limb of a pedestrian when impacted by high-bumper vehicles and (2) The effectiveness of the compensation method for the lack of the upper body by increasing impact height of the FlexPLI for high-bumper vehicles.
2015-04-14
Technical Paper
2015-01-1446
Timothy P. Austin, David P. Plant, Joseph E. LeFevre
Abstract The use of Heavy Vehicle Event Data Recorders (HVEDRs) in collision analysis has been well recognized in past research. Numerous publications have been presented illustrating data accuracy both in normal operating conditions as well as under emergency braking conditions. These data recording devices are generally incorporated into Electronic Control Modules (ECMs) for engines or Electronic Control Units (ECUs) for other vehicular components such as the Anti-Lock Brake System. Other research has looked at after-market recorders, including publically-available Global Positioning System (GPS) devices and fleet management tools such as Qualcomm. In 2009, the National Fire Protection Association (NFPA) incorporated a Vehicle Data Recorder (VDR) component into their Standard for Automotive Fire Apparatus. The purpose of this was to “…capture data that can be used to promote safe driving and riding practices.”
2015-04-14
Technical Paper
2015-01-1447
Hirotoshi Ishikawa, Kunihiro Mashiko, Tetsuyuki Matsuda, Koichi Fujita, Asuka Sugano, Toru Kiuchi, Hirotsugu Tajima, Masaaki Yoshida, Isao Endou
Abstract Event Data Recorders (EDRs) record valuable data in estimating the occupant injury severity after a crash. Advanced Automatic Collision Notification (AACN) with the use of EDR data will determine the potential extent of injuries to those involved in motor vehicle accidents. In order to obtain basic information in injury estimation using EDR data, frontal collisions for 29 vehicles equipped with EDRs were analyzed as a pilot study by retrieving the EDR data from the accident vehicles and collecting the occupant injury data from the database of an insurance company. As a result, the severity of occupant injury was closely related to the Delta V recorded on an EDR. However, there were several cases in which the predicted injury level was overestimated or underestimated by the Delta V. Therefore, caution is required when predicting the level of injury in frontal collisions based upon the Delta V alone.
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