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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
2015-01-1430
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
2015-01-1421
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
2015-01-1428
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
2015-01-1473
Kalu Uduma
The National Highway Transportation Safety Administration (NHTSA) issued the FMVSS 226 ruling in 2011. It established test procedures to evaluate ejection mitigation countermeasures that are intended to help minimize the likelihood of a complete and/or partial ejection of vehicle occupants through the side windows during rollover or side impact events. One of the countermeasures that may be used for compliance of this new safety ruling is a deployable restraint; specifically a Side Airbag Inflatable Curtain (SABIC). This paper discusses how three key phases of the optimization strategy in the Design for Six Sigma (DFSS), namely, Identify; Optimize and Verify (I_OV), were implemented in CAE to develop an improved simulation response, with respect to the FMVSS 226 test requirements of a SABIC. The simulated SABIC system is intended for a generic SUV and potentially also for a generic Truck type vehicle.
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
2015-01-1462
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
2015-01-1403
A host of new technologies, features and functions are continuously being added to vehicles to make the driving task and journey safe, pleasant, relaxing, enjoyable, and even exciting for the driver. An encompassing framework for research has been to understand and push further the need for ‘driver wellness’, the definition for which is still elusive. Suffice to say that ‘wellness’ is reflected in feeling good before, during and after the drive. Objective measures, primarily driver physiology, reflect wellness, but in an as yet not fully understood way. Murphey and Kochhar [1, 2] developed a Transportable Instrument Package (TIP) for in-vehicle on-the road driving data recording, and used machine learning and neural networks to explore the underlying relationships. In this paper we report on research that shows how in-vehicle, on-the-road driver physiological measures can be used to predict the driver’s intention to change lanes, even before such a lane-change is initiated.
2015-04-14
Technical Paper
2015-01-1408
Kristofer D. Kusano, Hampton C. Gabler
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 (FARS) and the National Motor Vehicle Crash Causation Survey (NMVCCS).
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
2015-01-1413
Louis Tijerina
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
2015-01-1598
Milad Jalaliyazdi, Amir Khajepour, Shih-Ken Chen, Bakhtiar Litkouhi
In this paper, the problem of stability control of an electric vehicle is addressed. To this aim, it is required that the vehicle follows a desired yaw rate at all driving/road conditions. The desired yaw rate is calculated based on steering angle, vehicle speed, vehicle geometric properties as well as road condition. The vehicle response is modified by torque vectoring on front and/or rear axles. This control problem is subject to several constraints. The electric motors can only deliver a certain amount of torque at a given rotational speed. In addition, the tire capacity also plays an important role in the stability control. It limits the amount of torque they can transfer without causing wheel over spinning. These constraints make Model Predictive Control (MPC) approach a suitable choice, because it can explicitly consider the constraints of the control problem, in particular the tire capacity, and help to prevent tire saturation, which is often the onset of vehicle instability.
2015-04-14
Technical Paper
2015-01-0214
Ramya deshpande, Krishnan kutty, Shanmugaraj Mani
In modern cars, the Advanced Driver Assistance Systems (ADAS) is cardinal point for safety and regulation. The proposed method detects visual saliency regions in a given image. Multiple ADAS systems require many sensors and multicore processors for fast processing of data in real time; which leads to the increase in cost. In order to balance the cost and safety, the system should process only required information and neglect the rest. Human visual system perceives only important content in the scene while leaving rest of portions unprocessed. The studies on human psycho visual system hypothesize similar behavior in human perception. The proposed method aims to model the similar behavior in computer vision with the concept of visual saliency. Saliency in still images is computed by color, frequency and positional difference. A region is salient, if its color or pattern is unique. The color difference between the regions in Lab Space highlights the visual difference.
2015-04-14
Technical Paper
2015-01-0657
Binglu Tu
This innovation is a Developed Anti-Lock Brake System (DABS for short) to automatically and precisely identify, correct and verify the peak-value slip ratio S0'' (i.e. braking force = adhesion force) when ε (namely the utilization ratio of adhesion coefficient, which is defined as the quotient of maximum braking strength divided by adhesion coefficient when ABS works) =1, and control S0'' to output continuously. It is a revision on the theory, method and algorithm of current ABS control that intermittently produces S0''. The objects are to eliminate the hidden unsafety of sideslip or ε<1 due to excessive or insufficient braking force, have more simplified structure and reduced costs than ABS, and improve the eligibility from ε≥0.75 to ε≥0.95.
2015-04-14
Technical Paper
2015-01-1433
Matthew Brach, Richard Mink, Raymond Brach
This paper presents a novel 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 conditions to reconstruct a collision. These conditions correspond to known or prescribed collision information (physical evidence) and can be incorporated into the optimized collision reconstruction technique in a variety of means 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) or engine control modules (ECM). The technique is presented using the Planar Impact Mechanics (PIM) collision model in combination with the Solver utility in Microsoft Excel.
2015-04-14
Technical Paper
2015-01-1476
Selvakumar P, Arun Mahajan, R Murasolimaran, Elango chinnasamy
Roll-over protective structures (ROPS) are safety devices which provide a safe environment for the tractor operator during an accidental rollover. The ROPS must pass either a dynamic or static testing sequence or both in accordance with SAE J2194. These tests examine the performance of ROPS to withstand a sequence of loadings and to see if the clearance zone around the operator station remains intact in the event of an overturn. In order to reduce costs and shorten product development cycle, non-linear finite element (FE) analysis is practiced routinely in ROPS design and development. Often correlating the simulation with the results obtained from testing a prototype validates the CAE model and its assumptions. This research has the proposal of showing the correlation between simulation and prototype test results of tractor ROPS. The FE analysis follows SAE procedure J2194 for testing the performance of ROPS.
2015-04-14
Technical Paper
2015-01-1487
Andreas Teibinger, Harald Marbler-Gores, Harald Schluder, Veit Conrad, Hermann Steffan
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
2015-01-1418
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
2015-01-1451
Venkat 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
2015-01-1411
Caroline Crump, David Cades, Robert Rauschenberger, Emily Hildebrand, Jeremy Schwark, Brandon Barakat
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
2015-01-1417
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
2015-01-1410
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
2015-01-0262
Aline Cristina Dos Santos Satvanyi, Pablo Oliveira Antonino
ISO 26262 is a relevant safety standard in the automotive industry that strongly emphasizes functional safety management in the early phases of system development. Functional safety aims at mitigating unacceptable risk or injury to humans and/or to the environment either directly or indirectly. To this end, one of the recommendations of ISO 26262 is to perform Failure Mode, Effects and Criticality Analysis (FMECA), which aims at evaluating and documenting the impact of potential failures of each system functionality. Each potential failure is then classified according to the severity of the effect that it might cause in case of failure and appropriate prevention and detection actions must be assigned to control or eliminate the hazard. In the past, FMEA was only performed at the system’s physical level (hardware), where failure modes are usually associated with physical components and are caused by wear or other physical damages to the system.
2015-04-14
Technical Paper
2015-01-1409
Joseph Yoon, Kajetan Kietlinski, Freerk Bosma
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
2015-01-0319
Reena Kumari Behera, Jiji Gangadharan, Krishnan kutty, Smita Nair, Vinay Vaidya
Pedestrian fatalities in road accidents are increasing exponentially. The insight shows a crucial need for coming up with a real time pedestrian detection system on vehicles. This paper presents a vision based pedestrian detection system. The methods available in literature are mostly classifier based that is applied at various image scales, which makes it inefficient for real time application. The presented algorithm is a novel method that accurately segments the pedestrian regions in real time. The fact that the pedestrians are always vertically aligned is taken into consideration. As a result, the edge image is scanned from bottom to top and left to right. Both the color and edge data is combined in order to form the segments. The segmentation is highly dependent on the edge map. Even a single pixel dis-connectivity would lead to incorrect segments. To improve this, a novel edge linking method is performed prior to segmentation.
2015-04-14
Technical Paper
2015-01-1472
Roberto Arienti, Carlo Cantoni, Massimiliano Gobbi, Giampiero Mastinu, 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
2015-01-1412
Xuan Zhou, Walter Niewoehner
The presentation and paper will explain a new algorithm-based approach to fasten future advanced driver assistance systems (ADAS) with simultaneously increasing the reliability. In the past the TTC (time to collision) was used to calculate and forecast traffic situations leading to a collision with an obstacle moving in front of the own vehicle in the same direction or coming towards it. Situations with the trajectories of the involved parties not being in-line (e.g. crossing, lane changing manoeuvres), parties changing the direction of movement, or parties changing the speed are more complex to calculate. The new method developed bases on an algorithm using the data from the area under sensor surveillance (e.g. by radar) to calculate a so-called collision tube. The collision tube describes the relative trajectories of the own vehicle and those of other traffic participants or obstacles.
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
2015-01-1478
Michelle Heller, William Newberry
Occupant kinematics during rollover motor vehicle collisions have been investigated over the past thirty years utilizing Anthropomorphic Test Devices (ATDs) in various test methodologies such as dolly rollover tests, CRIS testing, spin-fixture testing, and ramp-induced rollovers. Recent testing has utilized steer-induced rollovers to gain a deeper understand into vehicle kinematics, including the vehicle’s pre-trip motion (Asay et al., 2009; Asay et al., 2010). The current test series utilized ATDs in steer-induced rollovers to investigate occupant kinematics throughout the entire rollover sequence, from pre-trip vehicle motion to the final rest position. Two test vehicles (a sedan and a pickup truck) were fully instrumented, and each contained two restrained 50th percentile male ATDs in the front outboard seating positions. The pickup truck was equipped with rollover-activated side-curtain airbags that deployed prior to the first ground contact.
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.
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