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Viewing 61 to 90 of 17251
2017-03-28
Technical Paper
2017-01-1413
Nathan A. Rose, Neal Carter, David Pentecost, Alireza Hashemian
This paper investigates the dynamics of single-vehicle motorcycle crashes that occur on curves and identifies rider actions that contribute to causing these crashes. Physical evidence and physical principles that would enable a reconstructionist to determine when these actions are present in a particular crash are identified. The investigation is carried out by analyzing video footage of 10 motorcycle crashes that all occurred on a particular curve (Edwards Corner) on a section of the Mulholland Highway called “The Snake.” This section of highway is located in the Santa Monica Mountains of California. All of the video footage of these crashes was captured by a videographer who regularly takes video of motorcyclists traversing this curve and posts crash videos on YouTube. To aid evaluation of these crashes, the authors mapped Edwards Corner using both a Sokkia total station and a Faro laser scanner.
2017-03-28
Technical Paper
2017-01-1424
Mark Fabbroni, Jennifer Rovt, Mark Paquette
Collision reconstruction often involves calculations and computer simulations, which require an estimation of the weights of the involved vehicles. Although weight data is readily available for automobiles and light trucks, there is limited data for heavy vehicles, such as tractor-semitrailers, straight trucks, and the wide variety of trailers and combinations that may be encountered on North American roads. Although manufacturers always provide the gross vehicle weight ratings (GVWR) for these vehicles, tare weights are often more difficult to find, and in-service loading levels are often unknown. The resulting large uncertainty in the weight of a given truck can often affect reconstruction results. In Canada, the Ministry of Transportation of Ontario conducted a Commercial Vehicle Survey in 2012 that consisted of weight sampling over 45,000 heavy vehicles of various configurations.
2017-03-28
Technical Paper
2017-01-0367
Yueqian Jia PhD, Yu-wei Wang, Yuanli Bai
A fully modularized framework was established to combine isotropic, kinematic, and cross hardening behaviors under non-monotonic loading conditions for advanced high strength steels. Experiments under two types of non-proportional loading conditions were conducted along different orientations, 1) uniaxial compression-tension reversal loading, and 2) two-step uniaxial tension, known as cross-loading conditions, with different pre-strains. The calibrated new model using AK Steel DP980 is decoupled between isotropic and kinematic hardening behaviors, and independent on both anisotropic yield criterion and fracture model. Good correlation was observed between experimental and modeled results. KEYWORDS: Constitutive Modeling, Advanced High Strength Steel, Isotropic Hardening, Kinematic Hardening, Cross Hardening, Non-linear Strain Path
2017-03-28
Technical Paper
2017-01-1255
Zhihong Wu, Ke lu, Yuan Zhu, Xiaojun Lei, Liqing Duan, Jian_ning Zhao
Permanent magnet synchronous motors (PMSM) are widely used in the electric vehicles for their high power density and high energy efficiency. And the motor control system for PMSMs is one of the most safety critical systems in electric vehicles, because potential failures in this system can lead to serious harm to the human’s body, so normally a high automotive safety integrity level (ASIL) will be assigned to this system. In this paper, an ASIL-C motor control system based on a multicore micro-controller is presented. Meanwhile, since there are more and more connectivities available on the vehicle, secure onboard communication conformed to the AUTOSAR standard is also implemented in the system to prevent external attack.
2017-03-28
Technical Paper
2017-01-0050
Mario Berk, Hans-Martin Kroll, Olaf Schubert, Boris Buschardt, Daniel Straub
With increasing levels of driving automation, the information provided by automotive environment sensors becomes highly safety relevant. A correct assessment of the sensor’s reliability is therefore crucial for ensuring the safety of the customer functions. There are currently no standardized procedures or guidelines for demonstrating the reliability of the sensor information. Engineers are faced with setting up test procedures and estimating efforts. Statistical hypothesis tests are commonly employed in this context. In this contribution, we present an alternative method based on Bayesian parameter inference, which is easy to implement and whose interpretation is more intuitive for engineers without a profound statistical education. It also enables a more realistic representation of dependencies among errors.
2017-03-28
Technical Paper
2017-01-0363
Karthik Ramaswamy, Vinay L. Virupaksha, Jeanne Polan, Biswajit Tripathy
EPP foams are most commonly used in automotive applications for pedestrian protection and to meet low speed bumper regulatory requirements. In today’s automotive world the design of vehicles are predominantly driven by CAE. This makes it necessary to have validated material model for EPP foams in order to simulate and predict performance under various loading conditions. Since most of the automotive OEMs depend on local material suppliers for their global vehicle applications it is necessary to understand the variation in mechanical properties of the EPP foams and their effect on performance predictions. In this paper, EPP foams from three suppliers across global regions are characterized to study the inter-supplier variation in mechanical properties. In order to understand the effect of inter-supplier variation on vehicle performance, LSDYNA rate dependent material model is developed and validated for low speed and pedestrian protection load cases.
2017-03-28
Technical Paper
2017-01-0264
Venkatesh Babu, Ravi Thyagarajan, Jaisankar Ramalingam
In this paper, the capability of three methods of modelling detonation of high explosives (HE) buried in soil viz., (1) coupled discrete element & particle gas methods (DEM-PGM) (2) Structured - Arbitrary Lagrangian-Eulerian (S-ALE), and (3) Arbitrary Lagrangian-Eulerian (ALE),are investigated. The ALE method of modeling the effects of buried charges in soil is well known and widely used in blast simulations today Due to high computational costs, inconsistent robustness and long run times, alternate modeling methods such as Smoothed Particle Hydrodynamics (SPH) and DEM are gaining more traction. In all these methods, accuracy of the analysis relies not only on the fidelity of the soil and high explosive models but also on the robustness of fluid-structure interaction. These high-fidelity models are also useful in generating fast running models (FRM) useful for rapid generation of blast simulation results of acceptable accuracy.
2017-03-28
Technical Paper
2017-01-0293
Tina Hull
Advances in technology allow machine safeguarding to shift from a system that completely shuts down the hazardous part of a machine regardless of the action, to one with a controlled response. It can be based on conditions such as the type of task, how it is performed, entry and exit locations, and operator movement within the hazard zone. A variety of options are available using existing principles with enhanced safety features. Component reliability data is used to calculate predicted failure rates. When it is used as part of a preventative maintenance program to replace components before they fail, it becomes a tool to reduce the probability of operators requiring increased future access into the hazard zone. Programming techniques such as function block to monitor component usage can be used to track actual system use and adjust reliability calculations.
2017-03-28
Technical Paper
2017-01-1442
Dawei Luo, Jianbo Lu, Gang Guo
This paper proposes a low-cost but indirect system which can be used for occupancy detection and occupant counting. The system can serve as a way to confirm the number of occupants riding inside a car or the only way to determine the occupancy where the other means is not reliable (e.g., 2nd row occupants might not use seat belts and weight sensors might not be installed). The system can be used for various mobility applications including car rental, fleet management, taxi, car sharing, etc. The system utilizes existing motion sensors, such as those used for the Roll Stability Control function, together with door ajar signals. The motion signature during occupant’s on-boarding and off-boarding a car is first extracted from the response of the vehicle body which are reflected by the motion sensors. Then the weight of the occupant, during on-boarding and off-boarding, is determined through fitting the vehicle response signals to a transient response from a vehicle model.
2017-03-28
Technical Paper
2017-01-0361
Amar Marpu, George Garfinkel, Patrick Maguire
Modeling of high voltage (HV) wires is an important aspect of vehicle safety simulations of electrified powertrains, in order to understand the potential tearing of the wire sheath or pinching of high voltage wiring. The behavior of these wires needs to be reviewed in safety simulations to identify potential hazards associated with a high voltage wire being exposed, severed or coming in contact with ground planes during a crash event. Modeling high voltage wire is challenging due to the complexity of the physical composition of the wire, which is usually comprised of multiple strands bundled and often twisted together to form the high voltage electrical conductor. This is further complicated by the existence of external insulating sheathing materials to prevent high voltage exposure during normal operating conditions. This paper describes a proposed method to model and characterize different types of high voltage wires for usage in component and vehicle level safety models.
2017-03-28
Technical Paper
2017-01-1430
Tony R. Laituri, Scott G. Henry
To consider injury trends and to establish bases for potential future risk analyses, we categorized head injuries in real-world frontal crashes as being "brain-related," "bone-related," and/or "otherwiserelated." Specifically, we studied adult drivers in towaway, 11-1 o'clock, full-engagement frontal crashes in the National Automotive Sampling System (NASS, 1995-2012 calendar years, 1985-2012 model-year light passenger vehicles). Those data were considered subject to three levels injury (AIS1+, AIS2+, AIS3+) , two levels of restraint (properly-belted, unbelted), and two eras of technology, based on driverairbag fitment (Older Vehicles, Newer Vehicles). For each injury level, 88 possible bins of data were formed to quantify injury rates for the various head-injury categories, eras, restraint levels, speed changes, and crash severities.
2017-03-28
Technical Paper
2017-01-1463
Feng Zhu, Clifford C. Chou
A new design methodology based on data mining theory has been proposed and used in the vehicle crashworthiness design. The method allows exploring the big crash simulation dataset to discover the underlying complicated relationships between response and design variables, and derive design rules based on the structural response to make decisions towards the component design. An S-shaped beam is used as an example to demonstrate the performance of this method. A large amount of simulations are conducted and the results form a big dataset. The dataset is then mined to build a decision tree. Based on the decision trees, the interrelationship among the geometric design variables are revealed, and then the design rules are derived to produce the design cases with good energy absorbing capacity. The accuracy of this method is verified by comparing the data mining model prediction and simulation data.
2017-03-28
Technical Paper
2017-01-0373
Fabian Jorg Uwe Koark, Christian Beul
Motivation – Achieving functional safety in mechatronic systems with growing product functionality is a major challenge in systems engineering. Following the current discussion, this challenge is mostly allocated to electronics and software development. For most of the scenarios this focus is feasible. Product design – the construction of the product – defines the properties and the appearance of the product by shape, material and assembly. So, the product design is often not under control of the safety management system. A hazardous deviation of part shape can be easily identified after the parts product or at least at its mounting. A wrong assembly is controlled by assembly documentation or data (e.g. screw torques) and identified at end of assembly line checks. The identification of a hazardous material choice depend on the product material class. Product materials can be separated into two classes: passive or active materials.
2017-03-28
Technical Paper
2017-01-1419
Smruti Panigrahi, Jianbo Lu, Sanghyun Hong
Characterizing or reconstructing incidents ranging from light to heavy crashes is one of the enablers for mobility solutions for fleet management, car-sharing, ride-hailing, insurance etc. While crashes involving airbag deployment are noticeable, light crashes without airbag deployment can be hidden and most drivers do not report these incidents. Frequent light crashes reveal not only abusive driver behaviors but also increase the probability of damaging a vehicle. In this paper, we are using vehicle responses together with a dynamics model to trace back if abnormal forces have been applied to a vehicle so as to detect light crashes. The crash location around the perimeter of the vehicle, the direction of the crash force, and the severity of the crashes are all determined in real-time based on on-board sensor measurements which has further application in accident reconstruction.
2017-03-28
Technical Paper
2017-01-1352
David Gardiner
The North American light duty vehicle fleet includes a substantial number of Flexible Fuel Vehicles (FFVs) which can operate on fuels containing up to 85% denatured ethanol. When these vehicles are operated in climatic regions with very cold winter temperatures, the portion of denatured ethanol in the fuel is normally reduced to well below 85% in order to improve fuel volatility. Both the U.S and Canadian standards for automotive spark ignition fuels include seasonal volatility requirements whose purpose includes the creation of fuel tank vapour space mixtures that are too rich to be flammable. However, there is limited information available about the actual temperature limits of flammability for real-world high ethanol (“E85”) and low ethanol (“E10”) blends, and the minimum vapour pressure values needed to achieve the desired temperature limits.
2017-03-28
Technical Paper
2017-01-0378
Yuta Imanami, Kunikazu Tomita PhD, Kazuaki Fukuoka, Kimihiro Nishimura
In order to develop a new carburizing steel material that realizes an intermediate heat treatment-free process in parts manufacturing, the cold forgeability of the as-rolled steel and suppression of abnormal grain growth of austenite were studied. It was shown that adjustment of Si, Mn and Cr, suppression of dynamic strain aging during cold forging, and an increase of ferrite by controlled rolling contribute to the reduction of deformation resistance. However, Nb precipitation control by fully utilizing mill manufacturing processes was also necessary for suppression of abnormal austenite grain growth. A new steel carburizing was developed by integrating these technologies, making it possible to eliminate annealing before cold forging and normalizing before carburizing simultaneously. Thus, the developed steel is an important innovation in the parts manufacturing process.
2017-03-28
Technical Paper
2017-01-1380
Richard Young
Dingus and colleagues recently estimated the crash odds ratios (ORs) for secondary tasks in the Strategic Highway Research Program Phase 2 (SHRP 2) naturalistic driving study. Their OR estimate for hand-held cell phone conversation (Talk) was 2.2, with a 95% confidence interval (CI) from 1.6 to 3.1. This Talk OR estimate is above 1, contrary to previous estimates below 1. A replication discovered two upward biases in their analysis methods. First, for video clips with exposure to a particular secondary task, Dingus and colleagues selected clips not only with exposure to that task, but often with concurrent exposure to other secondary tasks. However, for video clips without exposure to that task, Dingus and colleagues selected video clips without other secondary tasks. Hence, the OR estimate was elevated simply because of an imbalanced selection of video clips, not because of risk from a particular secondary task.
2017-03-28
Technical Paper
2017-01-1351
Vamshi Korivi, Steven McCormick, Steven Hodges
The US Army Tank Automotive Research, Development and Engineering Center (TARDEC) developed a unique physics based modeling & simulation (M&S) capability using Computational Fluid Dynamics (CFD) techniques to optimize Automatic Fire Extinguishing System (AFES) designs and complement vehicle testing for both occupied and unoccupied spaces of military ground vehicles. The modeling technique developed here is based on reduced global kinetics for computational efficiency and is applicable to fire suppressants that are being used in Army vehicles namely, bromotrifluoromethane (Halon 1301), heptafluoropropane (HFC-227ea, trade name FM200), sodium bicarbonate (SBC) powder, water + potassium acetate mixture, and pentafluoroethane (HFC-125). These CFD simulations are performed using High Performance Computers (HPC) that enable the Army to assess these designs inexpensively in a virtual world that is crucial for vehicle and soldier protection in this complex world.
2017-03-28
Technical Paper
2017-01-1195
Masahiro Kimoto
SAE standards require the function of a manual service disconnect (SD), when open, to remove any voltage between positive and negative rechargeable energy storage system (RESS) output terminals. Another SAE standard specifies that measured voltage across all external battery terminal sets shall be less than 60 VDC within 5 seconds after the manual disconnect is actuated with the automatic disconnect (e.g., contactors) closed. In this paper, the location of the service disconnect is reviewed to meet isolation requirement of the battery pack system. Battery architectures with service disconnect located at the most positive side, most negative side, and center of the array or the pack were studied. Voltage measurement points and single point failure modes were considered. It was found that SD location for a single contactor pack is most effective in reducing voltage potential at the terminals when placed on the other side of the contactor.
2017-03-28
Technical Paper
2017-01-1453
Sudip Sankar Bhattacharjee, Shahuraj Mane, Harsha Kusnoorkar, Sean Hwang, Matt Niesluchowski
Pedestrian protection assessment methods require multiple head impact tests on a vehicle’s hood and other front end parts. Assessment methods become more complicated for vehicles equipped with pyrotechnic deployment systems, that are typically used to lift up the hood surface for creating more deformation space prior to pedestrian head impact. Estimation of pedestrian head impact time, thus, becomes a critical requirement for performance validation of deployable hood systems. In absence of standardized physical pedestrian models, Euro-NCAP recommends a list of virtual pedestrian models that could be used by vehicle manufacturers, with vehicle FEA models, to predict the potential head impact time along the vehicle front end profile. FEA simulated contact time is used as target for performance validation of sensor and pyrotechnic deployable systems.
2017-03-28
Technical Paper
2017-01-1355
Paul H. DeMarois, Bill Pappas, William G. Ballard, Jeffrey R. Williams, Gregory West
Four full scale burn tests with four unique points of origins were conducted on aluminum body Ford F-150’s. The purpose of these burn tests was to determine if the point of origin could be accurately identified after the vehicle fires progressed to near complete burn (with near absence of the aluminum body panels.) The points origin for the four burn tests were: 1) Engine Compartment – driver’s side front of engine compartment, 2) Passenger Compartment – Instrument panel, driver’s side near the headlamp switch, 3) Passenger Compartment – passenger side rear seat, 4) Outside of Vehicle – passenger side front tire. Photographic, video, and temperature data was recorded to document the burn process from initiation to extinguishment. Post-fire analysis was conducted in an attempt to determine the point of origin based solely on the burn damage. The analysis showed that due to the lack of body structure remaining, no point of origin could be determined.
2017-03-28
Technical Paper
2017-01-0075
Shinya Kitayama, Toshiyuki Kondou, Hirokazu Ohyabu, Masaaki Hirose, Haneda Narihiro, Ryuta Maeda
In the future, autonomous vehicles will be realized. It is assumed that traffic accidents will be caused by the overconfidence to the autonomous driving system and the lack of communication between the vehicle and the pedestrian. We propose that one of the solutions is a display system to give the information the state of vehicle to pedestrians.In this paper, we studied how the information influence the motion of pedestrians. The vehicle gives the information, which is displayed on road by using of color light (red, yellow and blue), of the collision risk determined by the TTC (Time to Collision). The pedestrian is ordered to cross the road in several case of the TTC. In the presence of the TTC information, the number of the pedestrians, who did not cross the road in the case of short TTC (red light is displayed), increased from 52% to 67%. It is cleared that the pedestrians determined whether they crossed the road or not by the information effectively.
2017-03-28
Technical Paper
2017-01-1436
Edward Fatzinger, Jon Landerville
Various electronic control units from Kawasaki Ninja 300 motorcycles were tested in-situ in order to examine heuristically the capabilities and behavior of the event data recorders (EDR). The relevant hexadecimal data was downloaded from the ECU and translated using known and historically proven applications. The hexadecimal translations were then confirmed using data acquisition systems as well as the Kawasaki Diagnostic Software (KDS). Numerous tests were then performed to establish the algorithms which cause the EDR to record data. It was determined that the EDR recording “trigger” was caused by the activation of the tip-over sensor, which in turn shuts the engine off. In addition, specific conditions must be met with regards to the rear wheel rotation prior to engine shut-down.
2017-03-28
Technical Paper
2017-01-1202
Ben Tabatowski-Bush
The Battery Monitoring Integrated Circuit (BMIC) is a key technology for Battery Electronics in the electrification of vehicles. Generally speaking, every production hybrid, plug-in hybrid, and battery electric vehicle uses some type of BMIC to monitor the voltage of each lithium battery cell. In order to achieve Functional Safety for the traction battery packs for these electrified vehicles, most designs require higher ASIL ratings for the BMIC such as C or D. For the entire market of available BMIC’s, there is a generic feature set that can be found on almost every IC on the market, such as a front end multiplexer, one or more precision references, one or more Analog to Digital (A/D) converters, a power supply, communications circuits, and window comparators. There is also a fairly consistent suite of self-diagnostics, available on just about every available BMIC, to detect failures and enable achievement of the appropriate ASIL rating.
2017-03-28
Technical Paper
2017-01-1233
Mohamed A. Elshaer, Allan Gale, Chingchi Chen
Vehicle safety is of a paramount importance when it comes to plugging the vehicle to the electric utility grid. The impact of high voltage ground fault has been neglected or, if not, addressed by guidelines extracted from general practices, written in international standards. The agile accession in Electric Vehicle (EV) development deems an exhaustive study on safety risks pertaining to fault occurrence. While vehicle electrification offers a vital solution to oil scarcity, it is essential that the fast development of the number of electric vehicles on the road does not compromise safety. Meanwhile, the link between technology and demands of society must be governed by vehicle safety. In this paper a comprehensive study on high voltage (HV) fault conditions occurring in an EV will be conducted. In the next decade EVs are expected to be prevalent worldwide. Ground fault characteristics are significantly dependent on the earthing system.
2017-03-28
Technical Paper
2017-01-1459
HangMook Kim, Jae Kyu Lee, Jin Sang CHUNG
If the door opening problem occurs in side crash, it results in raising the possibility of passenger ejection and serious injury. Therefore, for the sake of passenger’s safety, various research on preventing door opening during side impact test is conducted. Even though there are many causes for door opening, this study dealing with inertia effect caused by impact energy. Until now, there have been two classical methods for preventing the door opening. One is increasing the balance weight and spring force. That counterbalances the outside handle’s opening direction moment. The other is the application of the blocking lever. That prohibits the outside handle’s movement mechanically in the event of side crash. Recently, it is shown that the trend of crash test enhances the safety of the passengers by increasing the speed and weight of MDB. As a result, the impact energy transmitted to the vehicle increases.
2017-03-28
Technical Paper
2017-01-1407
Helene G. Moorman, Andrea Niles, Caroline Crump, Audra Krake, Benjamin Lester, Laurene Milan, Christy Cloninger, David Cades, Douglas Young
Lane Departure Warning (LDW) systems, along with other types of Advanced Driver Assistance Systems (ADAS), are becoming more common in passenger vehicles, with the general aim of improving driver safety through automation of various aspects of the driving task. Drivers have generally reported satisfaction with ADAS with the exception of LDW systems, which are often rated poorly or even deactivated by drivers. One potential contributor to this negative response may be an increase in the cognitive load associated with lane-keeping when LDW is in use. The present study sought to examine the relationship between LDW, lane-keeping behavior, and concurrent cognitive load, as measured by performance on a secondary task. Participants drove a vehicle equipped with LDW in a demarcated lane on a closed-course test track with and without the LDW system in use over multiple sessions.
2017-03-28
Technical Paper
2017-01-1439
John C. Steiner, Christopher Armstrong
The use of the United States’ Global Positioning System (GPS) to assist with the management of large commercial fleets of vehicles is quickly becoming commonplace. The GPS system can be used to track fleet vehicles resulting in more efficient and safe operations by refining and streamlining routing and operations. GPS-based fleet telematics data is also valuable for reducing unnecessary engine idle times and minimizing fuel consumption. Driver performance and policy adherence can also be monitored, for example by transmitting data regarding seatbelt usage when there is vehicle movement. Despite its advantages for fleet management, there are performance limitations that affect the utility of the system for analysis and reconstruction of accidents. The U.S. Air Force, responsible for maintaining and operating the GPS space and control segments, publishes information about these limitations.
2017-03-28
Technical Paper
2017-01-0716
Randy Hessel, Zongyu Yue, Rolf Reitz, Mark Musculus, Jacqueline O'Connor
The goal of this paper is to present guidelines for interpreting soot natural luminosity images that are taken from within the combustion chamber of a single-cylinder research engine, which is fitted with a window in the piston-crown. In the experiments, fuel is injected near top-dead-center and luminosity from soot that forms as a result of the combustion process is imaged. Then, CFD simulations are run, from which soot luminosity and in-cylinder soot distributions are predicted. A luminosity to soot-distribution transfer function is developed from the CFD results and the transfer function is subsequently applied to the experimentally-obtained luminosity images in order to approximate soot distributions in the physical engine with improved accuracy. This method is applied to multiple operating conditions in order to develop the guidelines presented herein. Although this work builds on previous efforts, this is the authors’ first published work on this particular topic.
2017-03-28
Technical Paper
2017-01-1432
Tadasuke Katsuhara, Yoshiki Takahira, Shigeki Hayashi, Yuichi Kitagawa, Tsuyoshi Yasuki
This paper discusses mechanisms of spine fracture during racecar crash, and investigates possible modifications to the seat and driver restraint system to help reduce spine fracture risk. This study focused on an accident during the World Endurance Championship in which a driver sustained bony spine fractures at T11 and T12 as the racecar collided against the tire wall. Finite element (FE) simulations were analyzed to understand the spinal fracture mechanism, the driver kinematics and interactions between the driver and the seat/restraint system. This FE model incorporated the Total Human Model for Safety (THUMS) scaled to the driver size, a model of the detailed racecar cockpit and a model of the seat/restraint systems. A frontal impact deceleration pulse was applied to the cockpit model. In the simulation, the driver torso moved forward under the shoulder belt and the pelvis was restrained by the crotch belt and the front of the seat cushion.
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