Display:

Results

Viewing 1 to 30 of 3150
2015-04-14
Technical Paper
2015-01-1448
Lee Carr, Robert Rucoba, Dan Barnes, Steven Kent, Aaron Osterhout
With commercial availability of the Bosch Crash Data Retrieval Tool (CDR), the information stored in vehicle Event Data Recorders (EDRs) has increasingly been used to supplement traditional traffic crash data collection and reconstruction methods, allowing enhanced confidence levels in transportation safety research. The objective of this study was to assess the accuracy and reliability of EDR data images obtained with the Bosch CDR tool by comparing them to a known crash impulse. Multiple EDRs and necessary sensor arrays were mounted on a HYGE™ acceleration-type crash simulation sled system at various orientations representing different principal direction of force (PDOF) angles and subjected to controlled “crash” impulses, simulating a “deployment event” (DE) and triggering data to be saved in the EDRs. The data included in each EDR’s CDR report was compared to the known conditions of the impulse.
2015-04-14
Technical Paper
2015-01-1449
Ada H. Tsoi, John Hinch, Michael Winterhalter, H. Gabler
As specified in 49 CFR 563 (Part 563), event data recorder (EDR) data are required to survive crash tests as specified by Federal Motor Vehicle Safety Standard (FMVSS) 208 and FMVSS 214. EDR data have been shown to survive these crash tests, which represent most U.S. highway crashes. However, some have argued the need for greater survivability, including supporters of the not enacted U.S. Motor Vehicle Safety Act of 2010. Similar devices, such as flight data recorders (FDRs), have considerably more demanding data survivability requirements. Minimum standards for FDR survivability include 30 days of sea water immersion, 5 hours exposure to a 260°C fire, and 5 minutes of 1,000lb static crush. In some cases EDRs are exposed to more severe crashes, fire, and immersion; however, little is known about whether current EDR data are capable of surviving these events and whether such improvements are cost-effective.
2015-04-14
Technical Paper
2015-01-1444
Ada H. Tsoi, John Hinch, H. Gabler
The National Highway Traffic Safety Administration (NHTSA) established survivability requirements on Event Data Recorder (EDR) data for the first time in 49 CFR 563 (Part 563) in September 2012. This regulation requires EDRs to remain functional during and after compliance crash tests as specified in Federal Motor Vehicle Safety Standard (FMVSS) 208 and FMVSS 214. These tests are representative of a major proportion of the crashes that occur on the nation’s highways; however, there are always crashes that are outside the typical distributions. Recent legislative bills have suggested that these survivability requirements should exceed Part 563 in delta-v, and include fire and immersion specifications. Little is known about whether EDRs are capable of surviving these events or whether the data received by the EDRs can be recovered after these events.
2015-04-14
Technical Paper
2015-01-1475
Alan F. Asay, Jarrod Carter, James Funk, Gregory Stephens
A follow-up case study on rollover testing was conducted with an instrumented single full-size SUV under real-world conditions. The purpose of this study was to conduct a well-documented rollover event that could be utilized in evaluating various reconstruction methods and techniques over the phases associated with rollover accidents. The phases documented and discussed inherent to rollovers are: loss-of-control, trip, and rolling phases. With recent advances in technology, new devices and techniques were implemented to capture and document the events surrounding a vehicle rollover. These devices and techniques are presented and compared with previous test methodology. In this case study, an instrumented 1996 GMC Jimmy SUV was towed to speed and then released. A steering controller steered the vehicle through maneuvers intended to result in rollover. The SUV experienced two non-rollover events before the vehicle finally rolled 1-1½ times.
2015-04-14
Technical Paper
2015-01-1479
Adria Ferrer, Eduard Infantes
In September 2009 the National Highway Traffic Safety Administration (NHTSA) published a report that investigated the incidence of fatalities to belted non-ejected occupants in frontal crashes involving late-model vehicles. The report concluded that after exceedingly severe crashes, the largest number of fatalities occurred in crashes involving poor structural engagement between the vehicle and its collision partner, such as corner impacts, oblique crashes, or impacts with narrow objects. In response to these findings, NHTSA designed and developed a test procedure intended to mitigate the risk of injuries and fatalities related to motor vehicle crashes involving poor structural engagement. This research demonstrated that an offset impact between a moving deformable barrier (RMDB) and a stationary vehicle at a 15º angle can reproduce vehicle crush, occupant kinematics, and risk of injury seen in vehicle-to-vehicle crashes.
2015-04-14
Technical Paper
2015-01-1446
Timothy P. Austin, David P. Plant, Joseph E. LeFevre
The use of Heavy Vehicle Event Data Recorders (HVEDRs) in collision analysis has been 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.” The Standard requires minimum data elements, recording times, and sample rates.
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
Automatic Collision Notification (ACN) is spreading in many countries.ACN provides notification in the event of a traffic accident automatically when an automobile's air bags are deployed or when the occupant restraint system is activated. ACN also serves as a diagnostic tool to determine the potential extent of injuries to those involved in motor vehicle incidents. Emergency medical service (EMS) personnel can utilize this information to determine how quickly their services are needed and it can minimize the number of victims who might be transferred to medical facilities mistakenly by the initial triage group. Various Electronic Control Units (ECUs) are equipped in vehicles. Air bag ECUs control the deployment of the air bag system and record various information on an event data recorder (EDR) during collisions. Data on the occupants, vehicles, and collisions recorded in EDR could be used as a parameter for estimating the occupant injury severity in an accident.
2015-04-14
Technical Paper
2015-01-1439
Toshiyuki Yanaoka, Yasuhiro Dokko, Yukou Takahashi
To evaluate vehicle safety performance for Traumatic Brain Injuries (TBIs) in crashes, comprehensive injury criteria is required. Few research results for injury criteria focused on Diffuse Axonal Injury (DAI) in crashes or pedestrian impacts exist. We developed injury criteria based on the rotational rigid body motion of the head for occupant and pedestrian crashes. We used the mid-sized male human head/brain FE model to investigate correlation between injury criteria based on the rotational rigid body motion of the head and intracranial responses related to DAI. The input pulses applied to the skull of the head/brain model were determined from the head acceleration data, and articulated rigid body simulation results of frontal occupant and pedestrian crashes. Results showed low applicability of the injury criteria to pedestrian impacts, presumably due to the maximum rotational velocity occurring before head contact to the vehicle.
2015-04-14
Technical Paper
2015-01-1437
Tony R. Laituri, Raed E. El-Jawahri, Scott Henry, Kaye Sullivan
Various risk curves for head injury potential were assessed theoretically relative to field data. Specifically, two AIS2+ risk curves were studied: the HIC15-based risk curve from Mertz (1997) and the provisional, BRIC-based risk curve from Takhounts et al. (2013). These two risk curves were used to estimate attendant injury potential for belted drivers in full-engagement frontal crashes in the National Automotive Sampling System (NASS). The occupant responses pertaining to those crashes were estimated from representative math models, and the risk curves were used to convert event responses into event risks. The assessment was conducted from two perspectives: aggregate (0-56 kph) and a point-estimate (56 kph, barrier-like). Finally, the point-estimate assessment was supplemented by considering corresponding laboratory tests. The results from HIC15-based risk curve were understated, whereas the results from the BRIC-based risk curve were overstated.
2015-04-14
Technical Paper
2015-01-1490
Tony R. Laituri, Scott Henry, Kaye Sullivan
A study of belted driver injury in various types of frontal impacts in the US field data was conducted. Specifically, subject to the Frontal Impact Taxonomy of Sullivan et al. (2008), injury potential of belted drivers in non-rollover, frontal impacts in the National Automotive Sampling System (NASS) was assessed. The field data pertained to 1985 - 2013 model-year light passenger vehicles in 1995 - 2012 calendar years of NASS. Two levels of injury were considered: AIS2+ and AIS3+. For ease of presentation, we grouped the injury data into lower- or upper-body regions. Frontal impacts were binned into eight taxonomic groups: Full-engagement, Offset, Narrow, Oblique, Side-swipe corner, High/low vert (i.e., over- and under-ride crashes), DZY-No rail (i.e., distributed crashes, but with negligible frame rail involvement), and Other. The results of the survey yielded insights into the distribution of belted-driver injury in NASS.
2015-04-14
Technical Paper
2015-01-1486
Craig A. Markusic, Ram Songade
Full vehicle crash simulations typically require several days of effort from a highly skilled FE (finite element) analyst to set-up, execute, and analyze. The goal of this project was to create a simplified FE model of a side crash utilizing the same sophisticated software (LS-DYNA) that the FE analysts use along with a custom graphical user interface (GUI) that will allow an inexperienced user to set-up, execute, and analyze a number of side impact scenarios in a matter of hours, not days, and with very little training. The GUI allows the user to easily modify the performance characteristics of the side impact system that are critical to side crash performance including but not limited to intrusion rate, door liner stiffness, side airbag stiffness, side airbag time to fire, etc. The user can then compile and submit the model with a few simple clicks of a button.
2015-04-14
Technical Paper
2015-01-1443
Morteza Seidi, Marzieh Hajiaghamemar, James Ferguson, Vincent Caccese
Falls in the elderly population is an important concern to individuals, family, friends, 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, weight, and cost 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.
2015-04-14
Technical Paper
2015-01-1477
Robert Larson, Jeffrey Croteau, Cleve Bare, John Zolock, Daniel Peterson, Jason Skiera, Jason R. Kerrigan, Mark D. Clauser
Over the past two decades, extensive testing has been conducted to evaluate both the performance of vehicle structures and occupant protection systems in rollover collisions, as well the potential for injury though the use of Anthropomorphic Test Devices (ATDs). Traditionally, the rollover tests utilized a test fixture to initiate the rollover event. Examples of various test methodologies include dolly rollovers, inverted drop tests, ramp-induced rollovers, curb-tripped rollover, and CRIS Tests. More recently, programmable steering controllers have been used in pickup trucks and SUVs to initiate steering induced rollovers, primarily for studying the vehicle kinematics for accident reconstruction applications. This study presents a series of rollover tests utilizing a crew-cab pickup and a mid-sized sedan which resulted in a steering-induced soil-tripped rollover.
2015-04-14
Technical Paper
2015-01-1487
Andreas Teibinger, Harald Marbler-Gores, Harald Schluder, Veit Conrad, Hermann Steffan, Josef Schmidauer
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. This is due to the earlier availability and lower cost of hardware components in comparison to the whole vehicle. Current approaches mainly use originally moving deformable barriers and therefore a full vehicle test facility is needed. 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. The test bench is designed with simulations and includes a control for the force impact. This test bench is able to reproduce the same intrusion speeds as in whole vehicle tests and doesn’t block a full vehicle test facility.
2015-04-14
Technical Paper
2015-01-1472
Roberto Arienti, Carlo Cantoni, Massimiliano Gobbi, Giampiero Mastinu, Mario Pennati, Giorgio Previati
The lightweight seat of a high performance car is designed taking into account a rear impact. The basic parameters of the seat structure are derived resorting to the simulation of a crash test. A dummy is positioned on the seat and subject to a rear impulse. The simulations provide the dynamic loads acting on the seat structure, in particular the ones applied at the joint between the seat cushion and the seat backrest. Such a joint is simulated as a plastic hinge and dissipates some of the crash energy. By means of the simulations the proper parameters of the plastic hinge can be derived to design a safe seat. The simulations are validated by means of indoor tests with satisfactory results. By using the validated model, the influence of seat cushion and backrest parameters on seat passenger's injury are studied. An efficient tool has been developed for the preliminary design of lightweight seats for high performance cars.
2015-04-14
Technical Paper
2015-01-1703
John D. Bullough
Assessing the safety impacts of vehicle forward lighting is a challenge because crash data do not always contain details necessary to ascertain the role, if any, of lighting in crashes. The present paper will describe several approaches to evaluating the safety impacts of lighting using naturalistic driving data. Driving behavioral data and records of near-miss incidents might provide new opportunities to understand how forward lighting improves traffic safety.
2015-04-14
Technical Paper
2015-01-1415
Yasuhiro Matsui, Shoko Oikawa
The number of traffic deaths in Japan decreased over the past 20 years to 4373 in 2013. Among accident types of road-accident fatalities, only cyclist fatalities increased in number from 2012 to 2013, from 563 to 600, an increase of 7%. The Japanese government began assessing the safety performance of car bonnet tops in terms of pedestrian deaths in 2005, but there has been no effective regulation for cyclist protection in Japan. The implementation of countermeasures that reduce the severity of injuries and number of deaths in traffic accidents requires a detailed understanding of the features of cyclist injuries in vehicle-versus-cyclist accidents. The aim of this study is to clarify the circumstances in which cyclists are injured.
2015-04-14
Technical Paper
2015-01-1428
Shane Richardson, Andreas Moser, Tia Lange Orton, Roger Zou
Currently techniques that can be used to evaluate and analyse lateral impact speeds of vehicle crashes with poles are based on measuring the deformation crush and using lateral crash stiffness data to estimate the impact speed. However, in some cases the stiffness data is based on broad object side impacts rather than pole impacts. The premise is that broad object side impact tests can be used for narrow object impacts; previous authors have identified the fallacy of this premise. Publicly available pole crash test data is evaluated. A range of simulated pole impact tests at various speeds and impact angles are conducted on validated publicly available Finite Element Vehicle models of a 1991 Ford Taurus, a 1994 Chevrolet C2500 and a 1997 Geo Metro (Suzuki Swift), providing a relationship between impact speed, crush depth and impact angle. This paper builds on previous publications and contains additional pole tests and new Finite Element Analyses.
2015-04-14
Technical Paper
2015-01-1429
Jeffrey Aaron Suway, Judson Welcher
Federal Motor Vehicle Safety Standard (FMVSS) No. 108 has requirements for retroreflective tape at different entrance angles, up to 45 degree. In the author’s preliminary research, all DOT-C2 retroreflective tape on the market is advertised as meeting and exceeding FMVSS No. 108 requirements. The author’s literature review revealed that there have been no peer-reviewed publications measuring the performance of commercially available DOT-C2 retroreflective tape. Therefore, without additional study, an accident reconstruction expert cannot know exactly how a specific type of compliant tape would perform, beyond the minimum federal requirements. Therefore, the authors have measured the performance of different types of retroreflective tape with a laboratory grade retroreflectometer. The authors attempted to study a range of popular, commercially available, DOT-C2 retroreflective tape. In this study, 3M 963, 3M 983, Grote, and Trucklite DOT-C2 retoreflective tape was used.
2015-04-14
Technical Paper
2015-01-1427
Jay Przybyla, Jason Jupe, Thomas Rush, Rachel Keller
Vehicles involved in rollover accidents can leave debris trails which can include glass from broken windows. The glass patterns can be useful in identifying the vehicle path during the rollover and the location and orientation of the vehicle at various vehicle-to-ground impacts. The location of glass, which is often window specific, can be used to identify where the window fractured during the rollover sequence. The longevity of the glass debris fields, subject to various real-world conditions and disturbances (i.e. slope, weather, mowing, soil type, etc.), was tested over a period of two years. The glass debris fields were placed and mapped in multiple locations across the United States. Periodically during each year, the glass debris fields were examined and the new field extents were mapped. The comparison between the original debris field and the subsequent debris fields are presented.
2015-04-14
Technical Paper
2015-01-1432
Jeffrey Aaron Suway, Judson Welcher
Accident reconstruction experts are often asked to evaluate the visibility and conspicuity of objects in the roadway. It is common for some of these objects, and required by Federal Motor Vehicle Safety Standard (FMVSS) No. 108 for certain vehicles and trailers, to have red and white DOT-C2 retroreflective tape installed on several locations. Retroreflective tape is designed to reflect light back towards the light source, at the same entrance angle. FMVSS No. 108 has performance requirements for retroreflective tape at different entrance angles, up to 45 degree. The federal requirement for minimum performance of the retroreflective tape at 45 degrees is significantly less than the federal requirement for minimum performance of the retroreflective tape at 4 degrees. Additionally, the federal requirement for the minimum performance of white retroreflective tape is significantly different than the federal requirement for the minimum performance of red retroreflective tape.
2015-04-14
Technical Paper
2015-01-1430
Brian Gilbert, Joseph McCarthy, Ron Jadischke
Objectives: The analysis and modeling of vehicle crush in accident reconstruction has traditionally been based upon the use of linear crush-based, stiffness coefficients. Recent research has allowed for the calculation and implementation of non-linear crush coefficients. Through the use of Engineering Dynamics Corporation (EDC) accident reconstruction software Human-Vehicle-Environment (HVE), which contains the collision algorithm called DyMESH (DYnamic MEchanical SHell), these coefficients have increased the accuracy of predicted crash pulse data. Research on non-linear crush coefficients thus far has been limited to frontal impacts into rigid barriers. Side Impact tests are typically more complex than a frontal collision testing. One form of side impact tests involve a Moving Deformable Barrier (MDB) impacting a stationary subject vehicle at a crab angle of 26-27 degrees.
2015-04-14
Technical Paper
2015-01-1418
Shane Richardson, Nikola Josevski, Andreas Sandvik, Tandy Pok, Tia Lange Orton, Blake Winter, Xu Wang
Pedestrian throw distance can be used to evaluate vehicle impact speed for wrap or forward projection type pedestrian collisions. There have been multiple papers demonstrating relationships between the impact speed of a vehicle and the subsequent pedestrian throw distance. In the majority of instances the scenarios evaluated focused on the central width of the vehicle impacting the pedestrian. However based on investigated pedestrian collisions there is a depending on where and how the vehicle and pedestrian engaged with one another, the definition of the engagement can and does significantly influence the throw distance. PC-Crash was used to simulate multiple pedestrian impacts at multiple speeds and pedestrian throw distance impact speed contour plots were created. The pedestrian throw distance impact speed contour plots for a range of vehicle types and pedestrian sizes are presented.
2015-04-14
Technical Paper
2015-01-1419
Raymond M. Brach
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 from accident evidence. When this is the case almost all formulas and models lose their utility. The model developed by Han and Brach published 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. This approach provides versatility and allows variations of these variables to be taken into account for investigation of uncertainty.
2015-04-14
Technical Paper
2015-01-1416
Clay Coleman, Donald Tandy, Jason Colborn, Nicholas Ault
In the field of accident reconstruction, a reconstructionist will often inspect a crash scene months or years after a wreck has occurred. With this passage of time important evidence is sometimes no longer present at the scene (i.e. the vehicles involved in the crash, debris on the roadway, tire marks, gouges, paint marks, etc.). When a scene has not been totally documented with a survey by MAIT or the investigating officers, the only hope for the reconstructionist is to rely on police, fire department, security camera, or witness photographs. Traditionally, these photos can be used to locate missing evidence by employing photogrammetric techniques. However, these techniques are limited to planar surfaces and/or the pairing of discrete points between the original photographs and the scene.
2015-04-14
Technical Paper
2015-01-1417
Jeffrey Muttart
An analysis was performed utilizing the results from seven emergency steering studies and four routine lane change studies. Closed course and naturalistic research were included. These studies showed that in a routine lane change, Drivers reached peak lateral acceleration approximately one-second after steering after which lateral acceleration decreases linearly. These results were consistent with those from forward and backing acceleration research published elsewhere. Though, when drivers steered in response to an emergency situation, again, peak lateral acceleration occurred near one-second after steering onset, but average lateral acceleration decreased non-linearly. This non-linear decrease between onset of steering and completion of the maneuver was indicative of counter-steering, or reduced subsequent steering (straightening). The results show that the average lateral acceleration could be modeled with a power function.
2015-04-14
Technical Paper
2015-01-1420
John C. Steiner, John Olsen, Tom Walli, Tyler Kress, Christopher Armstrong, Ralph Gallagher, Stein Husher, John Kyes
Traditional accident reconstruction analysis methodologies include the study of the crush-energy relationship of vehicles. By analyzing the measured crush from a vehicle involved in a real world accident, to crush measured at a known energy in a crash test, the real world vehicle’s damage energy, the forces of the impact, and change-in-velocity (or Delta-V) can be evaluated. The largest source of publically available crash tests is from the National Highway Traffic Safety Administration (NHTSA), which conducts and reports on numerous Federal Motor Vehicle Safety Standard (FMVSS) compliance and New Car Assessment Program (NCAP) testing for many passenger vehicles for sale in the United States.
2015-04-14
Technical Paper
2015-01-1421
Dennis Turriff, David J. King, James Bertoch
Vehicle rollovers generate complicated damage patterns as a result of multiple vehicle-to-ground contacts. The goal of this work was to isolate and characterize specific directional features in coarse- and fine-scale scratch damage generated during a rollover crash. Four rollover tests were completed using stock 2001 Chevrolet Trackers. Vehicles were decelerated and launched from a rollover test device to initiate driver’s side leading rolls onto concrete and dirt surfaces. Gross vehicle damage and both macroscopic and microscopic features of the scratch damage were documented using standard and macro lenses, a stereomicroscope, and a scanning electron microscope (SEM). The most evident indicators of scratch direction, and thus roll direction, were accumulations of abraded material found at the termination points of scratch-damaged areas.
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.
Viewing 1 to 30 of 3150

Filter