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2017-09-18
WIP Standard
J1574/1
The parameters measured according to this SAE Recommended Practice will generally be used in simulating directional control performance in the linear range. (The “linear range” is the steady-state lateral acceleration below which steering wheel angle can generally be considered to be linearly related to lateral acceleration.) But they may be used for certain other simulations (such as primary ride motions), vehicle and suspension characterization and comparison, suspension development and optimization, and processing of road test data. This document is intended to apply to passenger cars, light trucks, and on-highway recreational and commercial vehicles, both non-articulated and articulated. Measurement techniques are intended to apply to these vehicles, with alterations primarily in the scale of facilities required.
2017-04-06
Magazine
Connectivity continues its advance More OEMs and Tier 1 suppliers are focusing on embedded telematic systems, hoping to displace aftermarket hardware. Tailoring fuel injection to control NOx The next big step to help heavy-duty diesel engines meet stricter emissions regulations involves adapting the fuel-injection system to the combustion needs. Active on safety Crash-avoidance technologies are vital "building blocks" to automate commercial vehicles, implement truck platooning and ultimately achieve zero accidents. Engineering with simulation and data Companies are discovering new simulation techniques, especially optimization; the next step is to combine simulation with sensor data and predictive analytics to create even more robust off-highway equipment.
2017-03-30
Magazine
Designing Electronic Warfare to Regain Airborne Military Dominance Certifying Composite Designs for Aerospace and Defense Electric Rockets and the Future of Satellite Propulsion Flat Cable Technology for Aerospace Applications XPONENTIAL 2017 – An AUVSI Experience Pulse Analysis Techniques for Radar and Electronic Warfare Reconfigurable Radio Tracks Flights Worldwide Development of an Optically Modulated Scatterer Probe for a Near-Field Measurement System Using Dempster-Shafer Fusion for Personnel Intrusion Detection Angular Random Walk Estimation of a Time-Domain Switching Micromachined Gyroscope Using Fisher Information Criteria for Chemical Sensor Selection via Convex Optimization Methods Luminescence Materials as Nanoparticle Thermal Sensors
2017-03-28
Technical Paper
2017-01-0407
Fei Huo, Huyao Wu
Abstract Biomechanics and biodynamics are increasingly focused on the automotive industry to provide comfortable driving environment, reduce driver fatigue, and improve passenger safety. Man-centered conception is a growing emphasis on the open design of automobile. During the long-term driving, occupational drivers are easily exposed to the neck pain, so it is important to reduce the muscle force load and its fatigue, which are not usually considered quantitatively during traditional ergonomics design, so standards related are not well developed to guide the vehicle design; On the other hand, the head-neck models are always built based on the statics theory, these are not sufficient to predict the instantaneous variation of the muscle force. In this paper, a head-neck model with multi DOFs is created based on multibody dynamics. Firstly, a driver-vehicle-road model considering driver multi-rigid body model, vehicle subsystems, and different ranks of pavement is built.
2017-03-28
Technical Paper
2017-01-1462
Haiyan Li, Xin Jin, Hongfei Zhao, Shihai Cui, Binhui Jiang, King H. Yang
Abstract Computational human body models, especially detailed finite element models are suitable for investigation of human body kinematic responses and injury mechanism. A real-world lateral vehicle-tree impact accident was reconstructed by using finite element method according to the accident description in the CIREN database. At first, a baseline vehicle FE model was modified and validated according to the NCAP lateral impact test. The interaction between the car and the tree in the accident was simulated using LS-Dyna software. Parameters that affect the simulation results, such as the initial pre-crash speed, impact direction, and the initial impact location on the vehicle, were analyzed. The parameters were determined by matching the simulated vehicle body deformations and kinematics to the accident reports.
2017-03-28
Technical Paper
2017-01-1562
Junyu Zhou, Chao Liu, Jan Kubenz, Günther Prokop
Abstract This paper describes a new hybrid algorithm for multibody dynamics in vehicle system dynamics which combines the advantages of both embedding technique algorithm and augmented formulation algorithm. An approach to vehicle dynamics modeling based on the hybrid algorithm is presented. Embedding technique algorithm has relatively small number of equations of motion. With help of this technique, an enhanced parametric vehicle dynamics model can be built, representing characteristic curves of suspension comprised in kinematic and compliance. Small number of equations enables the vehicle dynamics model to be simulated very efficiently. In comparison to embedding technique algorithm, the main benefit of augmented formulation algorithm is relatively simple for computer programming. With help of augmented formulation algorithm, the structure of the vehicle dynamic model can be easily extended.
2017-03-28
Journal Article
2017-01-1554
Ajith Jogi, Sujatha Chandramohan
Abstract Over the years, commercial vehicles, especially tractor-semitrailer combinations have become larger and longer. With the increasing demand for their accessibility in remote locations, these vehicles face the problem of off-tracking, which is the ensuing difference in path radii between the front and rear axles of a vehicle as it maneuvers a turn. Apart from steering the rear axle of the semitrailer, one of the feasible ways of mitigating off-tracking is to shift the fifth wheel coupling rearwards. However, this is limited by the distribution of the semitrailer’s load between the two axles of the tractor; any rearward shift of the fifth wheel coupling results in the reduction of the total static load on the tractor’s front axle and hence available traction. This may in turn lead to directional instability of the vehicle. In the present work, a new model of the fifth wheel coupling is proposed which the authors call Split fifth wheel coupling (SFWC).
2017-03-28
Journal Article
2017-01-1432
Tadasuke Katsuhara, Yoshiki Takahira, Shigeki Hayashi, Yuichi Kitagawa, Tsuyoshi Yasuki
Abstract This study used finite element (FE) simulations to analyze the injury mechanisms of driver spine fracture during frontal crashes in the World Endurance Championship (WEC) series and possible countermeasures are suggested to help reduce spine fracture risk. This FE model incorporated the Total Human Model for Safety (THUMS) scaled to a driver, 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 chest moved forward under the shoulder belt and the pelvis was restrained by the crotch belt and the leg hump. The simulation predicted spine fracture at T11 and T12. It was found that a combination of axial compression force and bending moment at the spine caused the fractures. The axial compression force and bending moment were generated by the shoulder belt down force as the driver’s chest moved forward.
2016-11-09
Book
This title includes the technical papers developed for the 2016 Stapp Car Crash Conference, the premier forum for the presentation of research in impact biomechanics, human injury tolerance, and related fields, advancing the knowledge of land-vehicle crash injury protection. The conference provides an opportunity to participate in open discussion about the causes and mechanisms of injury, experimental methods and tools for use in impact biomechanics research, and the development of new concepts for reducing injuries and fatalities in automobile crashes. The topics covered this year include: • Head/brain biomechanics • Thorax, spine, and pelvis biomechanics • Foot-Ankle Biomechanics • Injury and effect of directional impacts • Pedestrian and cyclist injury factors and testing • Commercial truck and pedestrian accidents factors and testing
2016-11-07
Technical Paper
2016-22-0017
Jason Stammen, Kevin Moorhouse, Brian Suntay, Michael Carlson, Yun-Seok Kang
When the Hybrid III 10-year old (HIII-10C) anthropomorphic test device (ATD) was adopted into Code of Federal Regulations (CFR) 49 Part 572 as the best available tool for evaluating large belt-positioning booster seats in Federal Motor Vehicle Safety Standard (FMVSS) No. 213, NHTSA stated that research activities would continue to improve the performance of the HIII-10C to address biofidelity concerns. A significant part of this effort has been NHTSA’s in-house development of the Large Omnidirectional Child (LODC) ATD. This prototype ATD is comprised of (1) a head with pediatric mass properties, (2) a neck that produces head lag with Z-axis rotation at the atlanto-occipital joint, (3) a flexible thoracic spine, (4) multi-point thoracic deflection measurement capability, (5) skeletal anthropometry representative of a seated child, and (6) an abdomen that can directly measure belt loading.
2016-11-07
Technical Paper
2016-22-0006
John R. Humm, Narayan Yoganandan, Frank A. Pintar, Richard L. DeWeese, David M. Moorcroft, Amanda M. Taylor, Brian Peterson
The objective of the present exploratory study is to understand occupant responses in oblique and side-facing seats in the aviation environment, which are increasingly installed in modern aircrafts. Sled tests were conducted using intact Post Mortem Human Surrogates (PMHS) seated in custom seats approximating standard aircraft geometry. End conditions were selected to represent candidate aviation seat and restraint configurations. Three-dimensional head center-of-gravity linear accelerations, head angular velocities, and linear accelerations of the T1, T6, and T12 spinous processes, and sacrum were obtained. Three-dimensional kinematics relative to the seat were obtained from retroreflective targets attached to the head, T1, T6, T12, and sacrum. All specimens sustained spinal injuries, although variations existed by vertebral level.
2016-10-25
Technical Paper
2016-36-0182
Eduardo Domingo Morales
Abstract There are many variables involved in the design of a front suspension, such as hardpoints' coordinates, steering geometry or even an anti-roll bar, which could make design difficult and time consuming. The MacPherson strut, due to the simplicity of its construction, less occupied space and low manufacturing cost, is widely used in vehicles in contrast to double wishbone and multi-link suspensions. Although its tuning process still demands time, it can be done with the aid of multibody dynamics simulations, by testing several configurations in a virtual way. In this work, a front suspension model with MacPherson strut is studied, so that the influence of variation of its parameters is analyzed in its elastokinematics behavior and in handling performance of a vehicle.
2016-10-25
Technical Paper
2016-36-0184
Eduardo Domingo Morales
Abstract The twist-beam suspension is widely used in vehicles due to the simplicity of its construction, less occupied space and its low manufacturing cost in comparison with multi-link suspension. The difficulties related to the design of a twist-beam axle concern the large number of possible configurations for twist-beam profile and the stiffness adjustment of axle beam and suspension arms. However, design process can be done with the aid of multibody dynamics simulations, by testing several configurations in a virtual way. In this work, a simplified twist-beam suspension model is studied, and the influence of variation of its parameters is analyzed in its elastokinematics behavior and in handling performance of a vehicle.
2016-09-27
Journal Article
2016-01-8030
Dai Quoc Vo, Hormoz Marzbani, Mohammad Fard, Reza N. Jazar
Abstract As long as a tire steers about a titled kingpin pivot, the point coming in contact with the road moves along its perimeter. This movement affects the determination of kingpin moments caused by the tire forces, especially for large steering angles. The movement, however, has been neglected in the literature on the steerable-tire-kinematics-related topics. In this investigation, the homogeneous transformation is employed to develop a kinematic model of a steering tire in which the instantaneous ground-contact point on the tire is considered. The moments about the kingpin axis caused by tire forces are then computed based on the kinematics. A four-wheel-car model is constructed for determining the kingpin moment of steering system during the low-speed cornering maneuver. The result shows that the displacement of the ground-contact point along the tire perimeter is significant for large steering angles.
2016-04-05
Journal Article
2016-01-1456
Rini Sherony, Renran Tian, Stanley Chien, Li Fu, Yaobin Chen, Hiroyuki Takahashi
Abstract Many vehicles are currently equipped with active safety systems that can detect vulnerable road users like pedestrians and bicyclists, to mitigate associated conflicts with vehicles. With the advancements in technologies and algorithms, detailed motions of these targets, especially the limb motions, are being considered for improving the efficiency and reliability of object detection. Thus, it becomes important to understand these limb motions to support the design and evaluation of many vehicular safety systems. However in current literature, there is no agreement being reached on whether or not and how often these limbs move, especially at the most critical moments for potential crashes. In this study, a total of 832 pedestrian walking or cyclist biking cases were randomly selected from one large-scale naturalistic driving database containing 480,000 video segments with a total size of 94TB, and then the 832 video clips were analyzed focusing on their limb motions.
2016-04-05
Journal Article
2016-01-1486
Qi Zhang, Bronislaw Gepner, Jacek Toczyski, Jason Kerrigan
Abstract While over 30% of US occupant fatalities occur in rollover crashes, no dummy has been developed for such a condition. Currently, an efficient, cost-effective methodology is being implemented to develop a biofidelic rollover dummy. Instead of designing a rollover dummy from scratch, this methodology identifies a baseline dummy and modifies it to improve its response in a rollover crash. Using computational models of the baseline dummy, including both multibody (MB) and finite element (FE) models, the dummy’s structure is continually modified until its response is aligned (using BioRank/CORA metric) with biofidelity targets. A previous study (Part I) identified the THOR dummy as a suitable baseline dummy by comparing the kinematic responses of six existing dummies with PMHS response corridors through laboratory rollover testing.
2016-04-05
Technical Paper
2016-01-1487
Zhenhai Gao, Chuzhao Li, Hongyu Hu, Chaoyang Chen, Hui Zhao, Helen Yu
Abstract At the collision moment, a driver’s lower extremity will be in different foot position, which leads to the different posture of the lower extremity with various muscle activations. These will affect the driver’s injury during collision, so it is necessary to investigate further. A simulated collision scene was constructed, and 20 participants (10 male and 10 female) were recruited for the test in a driving simulator. The braking posture and muscle activation of eight major muscles of driver’s lower extremity (both legs) were measured. The muscle activations in different postures were then analyzed. At the collision moment, the right leg was possible to be on the brake (male, 40%; female, 45%), in the air (male, 27.5%; female, 37.5%) or even on the accelerator (male, 25%; female, 12.5%). The left leg was on the floor all along.
2016-04-05
Journal Article
2016-01-1507
Jisi Tang, Qing Zhou, Bingbing Nie, Tsuyoshi Yasuki, Yuichi Kitagawa
Abstract Lower extremities are the most frequently injured body regions in vehicle-to-pedestrian collisions and such injuries usually lead to long-term loss of health or permanent disability. However, influence of pre-impact posture on the resultant impact response has not been understood well. This study aims to investigate the effects of preimpact pedestrian posture on the loading and the kinematics of the lower extremity when struck laterally by vehicle. THUMS pedestrian model was modified to consider both standing and mid-stance walking postures. Impact simulations were conducted under three severities, including 25, 33 and 40 kph impact for both postures. Global kinematics of pedestrian was studied. Rotation of the knee joint about the three axes was calculated and pelvic translational and rotational motions were analyzed.
2016-04-05
Technical Paper
2016-01-1506
David Poulard, Huipeng Chen, Matthew Panzer
Abstract Pedestrian finite element models (PFEM) are used to investigate and predict the injury outcomes from vehicle-pedestrian impact. As postmortem human surrogates (PMHS) differ in anthropometry across subjects, it is believed that the biofidelity of PFEM cannot be properly evaluated by comparing a generic anthropometry model against the specific PMHS test data. Global geometric personalization can scale the PFEM geometry to match the height and weight of a specific PMHS, while local geometric personalization via morphing can modify the PFEM geometry to match specific PMHS anatomy. The goal of the current study was to evaluate the benefit of morphed PFEM compared to globally-scaled and generic PFEM by comparing the kinematics against PMHS test results. The AM50 THUMS PFEM (v4.01) was used as a baseline for anthropometry, and personalized PFEM were created to the anthropometric specifications of two obese PMHS used in a previous pedestrian impact study using a mid-size sedan.
2016-04-05
Technical Paper
2016-01-1516
Takahiro Suzaki, Noritaka Takagi, Kosho Kawahara, Tsuyoshi Yasuki
Abstract Approximately 20% of traffic fatalities in United States 2012 were caused by rollover accidents. Mostly injured parts were head, chest, backbone and arms. In order to clarify the injury mechanism of rollover accidents, kinematics of six kinds of Anthropomorphic Test Devices (ATD) and Post Mortem Human Subjects (PMHS) in the rolling compartment, whose body size is 50th percentile male (AM50), were researched by Zhang et al.(2014) using rollover buck testing system. It was clarified from the research that flexibility of the backbone and thoracic vertebra affected to occupant’s kinematics. On the other hand, the kinematics research of body size except AM50 will be needed in order to decrease traffic fatalities. There were few reports about the researches of occupant kinematics using FE models of body sizes except AM50.
2016-04-05
Technical Paper
2016-01-1518
Carolyn W. Roberts, Jacek Toczyski, Jack Cochran, Qi Zhang, Patrick Foltz, Bronislaw Gepner, Jason Kerrigan, Mark Clauser
Abstract Multiple laboratory dynamic test methods have been developed to evaluate vehicle crashworthiness in rollover crashes. However, dynamic test methods remove some of the characteristics of actual crashes in order to control testing variables. These simplifications to the test make it difficult to compare laboratory tests to crashes. One dynamic method for evaluating vehicle rollover crashworthiness is the Dynamic Rollover Test System (DRoTS), which simulates translational motion with a moving road surface and constrains the vehicle roll axis to a fixed plane within the laboratory. In this study, five DRoTS vehicle tests were performed and compared to a pair of unconstrained steering-induced rollover tests. The kinematic state of the unconstrained vehicles at the initiation of vehicle-to-ground contact was determined using instrumentation and touchdown parameters were matched in the DRoTS tests.
2016-04-05
Technical Paper
2016-01-0334
Lucas e Silva, Tennakoon Mudiyanselage Tennakoon, Mairon Marques, Ana M. Djuric
Abstract A collaborative robot or cobot is a robot that can safely and effectively interact with human workers while performing industrial tasks. The ability to work alongside humans has increased the importance of collaborative robots in the automation industry, as this unique feature is a much needed property among robots nowadays. Rethink Robotics has pioneered this unique discipline by building many robots including the Baxter Robot which is exclusive not only because it has collaborative properties, but because it has two arms working together, each with 7 Degrees Of Freedom. The main goal of this research is to validate the kinematic equations for the Baxter collaborative robot and develop a unified reconfigurable kinematic model for the Left and Right arms so that the calculations can be simplified.
2015-12-31
WIP Standard
J670
The vehicle dynamics terminology presented herein pertains to passenger cars and light trucks with two axles and to those vehicles pulling single-axle trailers. The terminology presents symbols and definitions covering the following subjects: axis systems, vehicle bodies, suspension and steering systems, brakes, tires and wheels, operating states and modes, control and disturbance inputs, vehicle responses, and vehicle characterizing descriptors. The scope does not include terms relating to the human perception of vehicle response.
2015-11-09
Technical Paper
2015-22-0008
Jérôme Uriot, Pascal Potier, Pascal Baudrit, Xavier Trosseille, Philippe Petit, Olivier Richard, Sabine Compigne, Mitsutoshi Masuda, Richard Douard
Sled tests focused on pelvis behavior and submarining can be found in the literature. However, they were performed either with rigid seats or with commercial seats. The objective of this study was to get reference tests to assess the submarining ability of dummies in more realistic conditions than on rigid seat, but still in a repeatable and reproducible setup. For this purpose, a semi-rigid seat was developed, which mimics the behavior of real seats, although it is made of rigid plates and springs that are easy to reproduce and simulate with an FE model. In total, eight PMHS sled tests were performed on this semi-rigid seat to get data in two different configurations: first in a front seat configuration that was designed to prevent submarining, then in a rear seat configuration with adjusted spring stiffness to generate submarining. All subjects sustained extensive rib fractures from the shoulder belt loading.
2015-11-09
Technical Paper
2015-22-0009
Meghan K. Howes, Warren N. Hardy, Amanda M. Agnew, Jason J. Hallman
High-speed biplane x-ray was used to research the kinematics of the small intestine in response to seatbelt loading. Six driver-side 3-point seatbelt simulations were conducted with the lap belt routed superior to the pelvis of six unembalmed human cadavers. Testing was conducted with each cadaver perfused, ventilated, and positioned in a fixed-back configuration with the spine angled 30° from the vertical axis. Four tests were conducted with the cadavers in an inverted position, and two tests were conducted with the cadavers upright. The jejunum was instrumented with radiopaque markers using a minimally-invasive, intraluminal approach without inducing preparation-related damage to the small intestine. Tests were conducted at a target peak lap belt speed of 3 m/s, resulting in peak lap belt loads ranging from 5.4-7.9 kN. Displacement of the radiopaque markers was recorded using high-speed x-ray from two perspectives.
2015-11-09
Technical Paper
2015-22-0003
Masami Iwamoto, Yuko Nakahira
Accurate prediction of occupant head kinematics is critical for better understanding of head/face injury mechanisms in side impacts, especially far-side occupants. In light of the fact that researchers have demonstrated that muscle activations, especially in neck muscles, can affect occupant head kinematics, a human body finite element (FE) model that considers muscle activation is useful for predicting occupant head kinematics in real-world automotive accidents. In this study, we developed a human body FE model called the THUMS (Total HUman Model for Safety) Version 5 that contains 262 one-dimensional (1D) Hill-type muscle models over the entire body. The THUMS was validated against 36 series of PMHS (Post Mortem Human Surrogate) and volunteer test data in this study, and 16 series of PMHS and volunteer test data on side impacts are presented. Validation results with force-time curves were also evaluated quantitatively using the CORA (CORrelation and Analysis) method.
2015-11-09
Book
This title carries the papers developed for the 2015 Stapp Car Crash Conference, the premier forum for the presentation of research in impact biomechanics, human injury tolerance, and related fields, advancing the knowledge of land-vehicle crash injury protection. The conference provides an opportunity to participate in open discussion the causes and mechanisms of injury, experimental methods and tools for use in impact biomechanics research, and the development of new concepts for reducing injuries and fatalities in automobile crashes. The topics covered this year include: • Biomechanical Testing and Modeling of Human Response and Injury in Side Impacts • Biomechanics of the Thorax/Abdomen • Estimating Effects of Vehicle Mass and Active Safety Technologies on Injury/Fatality Risk • Computational Models and ATDs • Response and Injury to Pedestrians and Cyclists • Human and ATD Response to High-Speed Vertical Loading
2015-11-09
Book
This title carries the papers developed for the 2015 Stapp Car Crash Conference, the premier forum for the presentation of research in impact biomechanics, human injury tolerance, and related fields, advancing the knowledge of land-vehicle crash injury protection. The conference provides an opportunity to participate in open discussion the causes and mechanisms of injury, experimental methods and tools for use in impact biomechanics research, and the development of new concepts for reducing injuries and fatalities in automobile crashes. The topics covered this year include: • Biomechanical Testing and Modeling of Human Response and Injury in Side Impacts • Biomechanics of the Thorax/Abdomen • Estimating Effects of Vehicle Mass and Active Safety Technologies on Injury/Fatality Risk • Computational Models and ATDs • Response and Injury to Pedestrians and Cyclists • Human and ATD Response to High-Speed Vertical Loading
2015-04-14
Journal Article
2015-01-1478
Michelle Heller, Sarah Sharpe, William Newberry, Alan Dibb, John Zolock, Jeffrey Croteau, Michael Carhart, Jason Kerrigan, Mark Clauser
Abstract 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 maneuver-induced furrow tripped rollovers to gain further understanding of vehicle kinematics, including the vehicle's pre-trip motion. The current study consisted of two rollover tests utilizing instrumented test vehicles and instrumented ATDs to investigate occupant kinematics and injury response throughout the entire rollover sequences, from pre-trip vehicle motion to the position of rest. The two steer maneuver-induced furrow tripped rollover tests utilized a mid-sized 4-door sedan and a full-sized crew-cab pickup truck. The pickup truck was equipped with seatbelt pretensioners and rollover-activated side curtain airbags (RSCAs).
2015-04-14
Technical Paper
2015-01-1469
Yan Wang, Taewung Kim, Yibing Li, Jeff Crandall
Abstract Multibody human models are widely used to investigate responses of human during an automotive crash. This study aimed to validate a commercially available multibody human body model against response corridors from volunteer tests conducted by Naval BioDynamics Laboratory (NBDL). The neck model consisted of seven vertebral bodies, and two adjacent bodies were connected by three orthogonal linear springs and dampers and three orthogonal rotational springs and dampers. The stiffness and damping characteristics were scaled up or down to improve the biofidelity of the neck model against NBDL volunteer test data because those characteristics were encrypted due to confidentiality. First, sensitivity analysis was performed to find influential scaling factors among the entire set using a design of experiment.
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