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Viewing 61 to 90 of 17292
2017-03-28
Technical Paper
2017-01-1439
John C. Steiner, Christopher Armstrong, Tyler Kress
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
2017-01-0435
Koundinya Narasimha Kota, Bharath Sivanandham
Abstract Active roll control system offers better solution in improving the vehicle comfort and handling. There are various ways of active roll control system actuation like electrical, hydraulic and electro-hydraulic combination systems etc. For the current work, dual hydraulic actuator based active roll control mechanism is used. In this paper we have used integrated Model-In-Loop (MIL) based simulation approach to validate the active roll control system. Dual linear hydraulic actuators models and control logic for improving the roll dynamics of the vehicle is built using Matlab/Simulink. The desired car characteristics maneuver and road profiles are modeled in IPG Car maker(a Model in Loop based tool). Simulink model is integrated with Car Maker model for validating the performance in extreme cornering maneuvers, such as double steer step, slalom 18m, fishhook.
2017-03-28
Technical Paper
2017-01-0080
Qilu Wang, Bo Yang, Gangfeng Tan, Shengguang Xiong, XiaoXiao Zhou
Mountain road winding and bumpy,traffic accidents caused by speeding frequently happened, mainly concentrated on curves. The present Curve warning system research are based on CCD, but the existing obstacles, weather , driving at night and road conditions directly affect the accuracy and applicability. The research is of predictability based on the geographic information and can told the driver road information and safety speed ahead of the road to reduce the incidence of accidents. In this paper, the main research contents include: to estimate forward bend curvature through the node classification method based on the digital map. Braking based on vehicle dynamics before entering the curve is used to identify the road. The critical safety speed which do not occur side-slip is calculated with the radius of curvature , side friction factor and so on using the vehicle lateral dynamics.
2017-03-28
Technical Paper
2017-01-0091
Songyao Zhou, Gangfeng Tan, Kangping Ji, Renjie Zhou, Hao Liu
Mountainous roads have complex terrain. Traditional vehicle active safety system, such as ABS, only play a role when there's an emergency situation, and the loading rate is not high in the heavy vehicle. So the traffic accident rate is still high in the mountainous area. Researches show that if drivers react before the accident 2-3 s there could be 90% reduction in the accident rate. This safety speed warning system is combined with the digital map, which makes the drivers see the mountainous road information beyond the horizon. Compared to the road standard speed limit, the system combination with the road information and characteristics of heavy vehicle itself can provide a more accurate and more useful safety warning speed limit. It can effectively reduce the incidence of accidents.
2017-03-28
Technical Paper
2017-01-1307
Puneet Bahri, Praveen Balaj Balakrishnan, Ravi Purnoo Munuswamy
The change in thickness and work hardening that arise during the forming process are generally ignored in quasi-static analysis for Seat belt pull when performed on vehicle body. However, it is a well-known effect that the physical properties of steel can alter significantly during the manufacturing process. This comprises an increase of material stiffness due to plastic deformation as well as gage changes. Generally, these changes are of very local nature and in the past, crash software tools didn't support the introduction of these local effects, so that they couldn't be taken into account. In the meanwhile LS-DYNA has the capability to import information provided by stamping tools. Thereby a very important part of the material properties can be introduced into the quasi-static simulation models, leading to a significantly increased correlation to test results.
2017-03-28
Technical Paper
2017-01-0051
Jean GODOT, Adil ALIF, Sébastien Saudrais, Bertrand BARBEDETTE, Cherif LAROUCI
The assessment of the safety and the reliability for embedded systems is mainly performed early in the design cycle, at system level. The objective is to detect the potential failures which could lead to an undesirable event. Given the increasing critical aspect of the functions executed by the software in automotive and aeronautics, it becomes necessary to perform safety analysis at lower level of the design cycle such as at implementation stage. But, software models at this stage are complex and heterogeneous so the analysis are often manually realized. As the software models are also very large (thousands of basic software components), the analysis is labor-intensive and error-prone so it is not obvious to obtain relevant results. Therefore, the analysis on software models at implementation stage is often neglected.
2017-03-28
Journal Article
2017-01-0178
Mark Hepokoski, Allen Curran, Sam Gullman, David Jacobsson
Passive sensor (HVAC) manikins have been developed to obtain high resolution measurements of environmental conditions across a representative human body form. These manikins incorporate numerous sensors that measure air velocity, air temperature, radiant heat flux, and relative humidity. The effect of a vehicle’s climate control system on occupant comfort can be characterized from the data collected by an HVAC manikin. Equivalent homogeneous temperature (EHT) is often used as a first step in a cabin comfort analysis, especially since it reduces a large data set to a single intuitive number. However, the applicability of the EHT for thermal comfort assessment is limited since it does not account for human homeostasis, i.e., that the human body actively counter-balances heat flow with the environment in order to maintain a constant core temperature.
2017-03-28
Journal Article
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
Journal Article
2017-01-0365
Kentaro Sato, Takayuki Futatsuka, Jiro Hiramoto, Kei Nagasaka, Akira Akita, Takeshi Kashiyama
A simple testing method is proposed in order to investigate the ductile fracture in crashed automotive components using advanced and ultra-high strength steels. The fracture is often prone to occur at spot-weld joint and sheet edge. It is well known that the heat affected zone is weak point in ultra-high strength steel due to the annealed material around the nugget, and sheet edge is low ductility due to the damage of shearing. The proposed method is designed to simulate the ductile fracture started from spot weld point and sheared edge in deformed automotive components in crash event. Automotive steel sheets with a wide range of tensile strengths from 270 MPa to 1470 MPa, shown in Table 1, were examined to investigate the effect of material strength on the fracture behavior. Effect of cutting method including machining and laser cutting also investigated.
2017-03-28
Journal Article
2017-01-0368
Ying Zhao, Fangwu Ma, Longfan Yang, Yueqiang Wang, Hongyu Liang
The conventional hood with single material and stiffener structural form conceals some limitations on pedestrian protection and lightweight, not satisfying the requirements of structural strength, pedestrian protection and lightweight contradictory with each other at the same time. In this paper, a novel type hood is proposed to develop sandwich structure using architected cellular material with negative Poisson's ratio (NPR) configuration based on the decoupling thought of structural strength and energy absorption. Core-layer aluminum alloy material with NPR is used to meet the requirement of impact energy absorption, inner and outer skin using carbon fiber is selected to achieve high structural stiffness needed. This paper starts from the relations between geometric parameters of core-layer architected cellular material and mechanical properties, on this basis, the optimal geometric parameters can be expected using the multiobjective optimization method.
2017-03-28
Technical Paper
2017-01-1473
Ling Zheng, Yinan Gao, Zhenfei Zhan, Yinong Li
Several surrogate models such as radial basis function and Kriging models are developed to speed the optimization design of vehicle body and improve the vehicle crashworthiness. The error analysis is used to investigate the accuracy of different surrogate models. Furthermore, the Kriging model is used to fit the model of B-pillar acceleration and foot well intrusion. The multiquadric radial basis function is used to fit the model of the entire vehicle mass. These models are further used to calculate the acceleration response in B-pillar, foot well intrusion and vehicle mass instead of the finite element model in the optimization design of vehicle crashworthiness. A multi-objective optimization problem is formulated in order to improve vehicle safety performance and keep its light weight. The particle swarm method is used to solve the proposed multi-objective optimization problem.
2017-03-28
Technical Paper
2017-01-1468
Do Hoi KIm
Previous studies have dealt with the relationship between the injury criteria of dummies and vehicle drop during high-speed head on collisions. Ultimately, vehicle drops are found to worsen the injury criteria of dummies when exceeding 60mm during high-speed crashes. Also, vehicle drops affected the front side member of the vehicle body the most. The present study dealt with methods of improving vehicle drops by enhancing the connective structure of the front side member, the short gun, and the A pillar. Analyses on various vehicles confirm that arch-shaped front side members are an extremely important factor. Furthermore, if the short gun and A pillar are properly connected at the top of the arch shape on the front side member during crashes, the deformation energy of the vehicle could be converted to energy for lifting the A pillar lower. With a so-called body lift structure, BLS has been applied to the B/C segment vehicles of Hyundai and KIA.
2017-03-28
Technical Paper
2017-01-1360
John D. Bullough
Abstract Nighttime driving cannot be accomplished without vehicle headlighting. A growing body of evidence demonstrates the role of lighting on visual performance and in turn on nightttime driving safety in terms of crashes. Indirect impacts of lighting via comfort or other factors are less well understood, however. A two-part field study using real-world drivers of an instrumented vehicle was conducted to assess the potential role of oncoming headlight glare as a factor in driving behaviors that might be related to increased crash risks. In the first part of the study, drivers' behaviors when navigating through roadway intersections having different levels of crash risk were recorded in order to identify responses that were correlated with the risk level. In the second part, drivers were exposed to different levels of glare from oncoming headlights; several of the same risk-related behaviors identified in the first part of the study were exhibited.
2017-03-28
Technical Paper
2017-01-1353
Michael G. Leffert
Abstract This paper compares the material consumption and fire patterns which developed on four nearly identical compact sedans when each was burned for exactly the same amount of time, but with different wind speed and direction during the burns. This paper will also compare the effects of environmental exposure to the fire patterns on the vehicles. The burn demonstrations were completed at an outdoor facility in southeast Michigan on four late model compact sedans. The wind direction was controlled by placing the subject vehicle with either the front facing into the wind, or rear facing into the wind. Two of the burns were conducted when the average observed wind speed was 5-6kph and two of the burns were conducted at an average observed wind speed of 19kph.
2017-03-28
Technical Paper
2017-01-1380
Richard Young
Abstract 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
2017-01-1370
Hiroyuki Hara, Masaaki Kawauchi, Masayuki Katayama, Noriyuki Iwamori
Abstract Driving is an action that depends strongly on visual information. For displays in the cockpit, a combination of “ease of viewing” to inform the driver of danger early and “annoyance reduction” to avoid drops in the driver’s perception is needed. In this study, we tried to capture “ease of viewing” and “annoyance” in one fixed-quantity indicator. We took up a Camera Monitor System (CMS) as the subject and analyzed the effect that annoyance with the display used in CMSs has on driving behavior. Based on our analysis, we hypothesize that evaluating carelessness in viewing behavior is related evaluating to annoyance. Next, we chose a Detection Response Task (DRT) technique as a method to evaluate driving behavior influenced by this annoyance.
2017-03-28
Technical Paper
2017-01-1369
Abtine Tavassoli, Sam Perlmutter, Dung Bui, James Todd, Laurene Milan, David Krauss
Abstract Vision plays a key role in the safe and proper operation of vehicles. To safely navigate, drivers constantly scan their environments, which includes attending to the outside environment as well as the inside of the driver compartment. For example, a driver may monitor various instruments and road signage to ensure that they are traveling at an appropriate speed. Although there has been work done on naturalistic driver gaze behavior, little is known about what information drivers glean while driving. Here, we present a methodology that has been used to build a database that seeks to provide a framework to supply answers to various ongoing questions regarding gaze and driver behavior. We discuss the simultaneous recording of eye-tracking, head rotation kinematics, and vehicle dynamics during naturalistic driving in order to examine driver behavior with a particular focus on how this correlates with gaze behavior.
2017-03-28
Technical Paper
2017-01-1365
Michael Larsen
Abstract Vehicle certification requirements generally fall into 2 categories: self-certification and various forms of type approval. Self-certification requirements used in the United States under Federal Motor Vehicle Safety Standards (FMVSS) regulations must be objective and measurable with clear pass / fail criteria. On the other hand, Type Approval requirements used in Europe under United Nations Economic Commission for Europe (UNECE) regulations can be more open ended, relying on the mandated 3rd party certification agency to appropriately interpret and apply the requirements based on the design and configuration of a vehicle. The use of 3rd party certification is especially helpful when applying regulatory requirements for complex vehicle systems that operate dynamically, changing based on inputs from the surrounding environment. One such system is Adaptive Driving Beam (ADB).
2017-03-28
Technical Paper
2017-01-1364
Kashif Ali, Vikas Kumar, Virat Kalra
Abstract Vehicle occupant packaging and interior and exterior body design determine the overall visibility that the driver of the vehicle has. Visibility is also dependent on technological features inside and outside the passenger cell like proximity sensors and cameras etc. The focus of this research is to find and analyze the visibility percentages, blind spot angles and blind spot areas using statistical data both individually and as vehicle class put together in order to justify the need for standardization of basic visibility enhancing aids. This study has an added significance considering the Indian road transportation statistics. On an average, 16 people die every hour due to road accidents in India. The aim is to focus on cases that affect visibility in low speed driving, coasting and reversing that causes loss to public and private property.
2017-03-28
Technical Paper
2017-01-1301
Deepak A. Patil, Hrishikesh Buddhe
Frontal collisions account for the majority of car accidents. This paper presents the energy absorption properties of hexagonal honeycomb structures of varying cellular geometries under frontal impact simulations. Honeycomb cellular meta-material structures offer many distinct advantages over homogenous materials because their effective material properties depend on both their constituent material properties and their geometric cell configuration. The effective static mechanical properties, such as the modulus of elasticity and rigidity and Poisson’s ratio, of honeycomb cellular meso-structures are control by variations of their cellular geometry. While the crushing responses in terms of energy absorption with different cellular shape observe a difference in the generalization of honeycombs with and varying geometric parameters. Unit assembly model technique is used to evaluate the performance vehicle in frontal load cases.
2017-03-28
Technical Paper
2017-01-1469
Tao Wang, Liangmo Wang, Jingxing Liu
To investigate the crashworthiness capacity of a M1 type commercial vehicle, the full-scale finite element (FE) model of the vehicle has been established. On basis of the FE model, the impact simulation subject to the 100% frontal impact has been carried out, and the results have been verified with the physical impact test. The analysis of the deformation path and the energy absorption indicates that the M1 vehicle lacks sufficient frontal deformation area and its peak crash acceleration (PCA) is too high, which raises a huge challenge for the sequent development of a safety restraint system. To enhance the crashworthiness of the M1 vehicle, some structural improvements have been implemented, with adding the energy absorbing box, improving the frontal frame parts and enhancing the front door. The frontal collapsing area has been investigated in order to figure out the layout position of the energy absorbing box.
2017-03-28
Journal Article
2017-01-0112
Mingming Zhao, Hongyan Wang, Junyi Chen, Xiao Xu, Yutong He
Rear-end accident is one of the most important collision modes in China, which often leads to severe accident consequences due to the high collision velocity. Autonomous Emergency Braking (AEB) system could perform emergency brake automatically in dangerous situation and mitigate the consequence. This study focused on the analysis of the rear-end accidents in China in order to discuss about the parameters of Time–to-Collision (TTC) and the comprehensive evaluation of typical AEB. A sample of 84 accidents was in-depth investigated and reconstructed, providing a comprehensive set of data describing the pre-crash matrix. Each accident in this sample is modeled numerically by the simulation tool PC-Crash. In parallel, a model representing the function of an AEB system has been established. This AEB system applies partial braking when the TTC ≤ TTC1 and full braking when the TTC ≤ TTC2.
2017-03-28
Technical Paper
2017-01-1400
Keyu Qian, Gangfeng Tan, Renjie Zhou, Binyu Mei, Wanyang XIA
Abstract Downhill mountain roads are the accident prone sections because of their complexity and variety. Drivers rely more on driving experience and it is very easy to cause traffic accidents due to the negligence or the judgment failure. Traditional active safety systems, such as ABS, having subjecting to the driver's visual feedback, can’t fully guarantee the downhill driving safety in complex terrain environments. To enhance the safety of vehicles in the downhill, this study combines the characteristics of vehicle dynamics and the geographic information. Thus, through which the drivers could obtain the safety speed specified for his/her vehicle in the given downhill terrains and operate in advance to reduce traffic accidents due to driver's judgment failure and avoid the brake overheating and enhance the safety of vehicles in the downhill.
2017-03-28
Technical Paper
2017-01-1399
Bin Wu, Xichan Zhu, Jianping Shen, Xuejun Cang, Lin li
Abstract A driver steering model for emergency lane change based on the China naturalistic driving data is proposed in this paper. The steering characteristic of three phases is analyzed. Using the steering primitive fitting by Gaussian function, the steering behaviors in collision avoidance and lateral movement phases can be described, and the stabilization steering principle of yaw rate null is found. Based on the steering characteristic, the near and far aim point used in steering phases is analyzed. Using the near and far aim point correction model, a driver steering model for emergency lane change is established. The research results show that the driver emergency steering model proposed in this paper performs well when explaining realistic steering behavior, and this model can be used in developing the ADAS system.
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
Abstract 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
2017-01-1417
Enrique Bonugli, Richard Watson, Mark Freund, Jeffrey Wirth
Abstract This paper reports on seventy additional tests conducted using a mechanical device described by Bonugli et al. [4]. The method utilized quasi-static loading of bumper systems and other vehicle components to measure their force-deflection properties. Corridors on the force-deflection plots, for various vehicle combinations, were determined in order to define the system stiffness of the combined vehicle components. Loading path and peak force measurements can then be used to evaluate the impact severity for low speed collisions in terms of delta-v and acceleration. The additional tests refine the stiffness corridors, previously published, which cover a wide range of vehicle types and impact configurations. The compression phase of a low speed collision can be modeled as a spring that is defined by the force-deflection corridors. This is followed by a linear rebound phase based on published restitution values [1,5].
2017-03-28
Technical Paper
2017-01-1413
Nathan A. Rose, Neal Carter, David Pentecost, Alireza Hashemian
Abstract This paper investigates the dynamics of four motorcycle crashes that occurred on or near a 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 four accidents were captured on video and they each involved a high-side fall of the motorcycle and rider. This article reports a technical description and analysis of these videos in which the motion of the motorcycles and riders is quantified. To aid in the analysis, the authors mapped Edwards Corner using both a Sokkia total station and a Faro laser scanner. This mapping data enabled analysis of the videos to determine the initial speed of the motorcycles, to identify where in the curve particular rider actions occurred, to quantify the motion of the motorcycles and riders, and to characterize the roadway radius and superelevation throughout the curve.
2017-03-28
Technical Paper
2017-01-1447
Pardeep K. Jindal, Rahul Makwana, Djamal Midoun, Edward Abramoski, Matthew Makowski, Ravi Kodwani
In 2012, the Insurance Institute for Highway Safety (IIHS) added a new frontal impact test to its vehicle crashworthiness rating protocol, often referred to as the “Small Overlap Rigid Barrier” (SORB) test. The objective of the present numerical study was to develop an innovative driver knee airbag (KAB) to address anthropomorphic test device (ATD) Knee-Thigh-Hip (KTH) response relative to the IIHS’s rating system of “Good, Acceptable, Marginal or Poor”. The approach used in this study utilized advanced morphing techniques in a sophisticated finite element (FE) model of a vehicle with an ATD and a restraint system. The key challenge in the study was to manage vehicle deformation with minimal changes to the KAB inflator and volume. Several KAB designs in terms of (width, height and depth) were simulated until a design resulted in changing the KTH rating from “Poor” to “Good”.
2017-03-28
Technical Paper
2017-01-1420
Kirsten White, Raymond Merala
Abstract This study presents a method to characterize the accuracy and precision of video-acceleration-position (VAP) devices, and presents results from testing of one such vehicle camera (“dashcam”) with global positioning system (GPS) used by taxi companies nationwide. Tests were performed in which vehicle kinematic data were recorded in a variety of real world conditions simultaneously by the VAP device, accelerometers, and a proven GPS-based speed sensing and data acquisition system. Data from the VAP device was compared to data collected by the reference instruments to assess timing, precision, and accuracy of reported parameters. Still images from the VAP video recording were compared with three dimensional laser scan data in order to analyze field of view. Several case studies are discussed, and some guidelines and cautions are provided for use of VAP data in accident reconstruction applications.
2017-03-28
Technical Paper
2017-01-1419
Smruti Panigrahi, Jianbo Lu, Sanghyun Hong
Abstract 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. 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. All of this information will be integrated to a feature called “Incident Report”, which enable reporting of minor accidents to the relevant entities such as insurance agencies, fleet managements, etc.
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