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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
2017-01-1466
Claudia De La Torre, Ravi Tangirala, Michael Guerrero, Andreas Sprick
Studies in the EU and the USA found higher deformation and occupant injuries in frontal crashes when the vehicle was loaded outboard (frontal crashes with a small overlap). Due to that, in 2012 the IIHS began to evaluate the small overlap front crashworthiness In order to solve this problem. A set of small overlap tests were carried out at IDIADA’S passive safety laboratory and the importance of identifying the forces applied in each structural element involved in small overlap crash were determined. One of the most important structural elements in the small overlap test is the wheel. Its interaction in a small overlap crash can modify the vehicle interaction at the crash, which at the laboratory the interaction is with a barrier. That interaction has a big influence at the vehicle development and design strategy. In order to study and understand in a better way the wheel kinematics and separation strategy, IDIADA developed with HATCI a small overlap sled test.
2017-03-28
Technical Paper
2017-01-0476
Seiji Furusako, Masatoshi Tokunaga, Masanori Yasuyama
In order to reduce the weight of automobile body, application of high strength steel sheets is expanding. And also a middle and high carbon steel is expected to be used to lower the environmental impact and cost in the field of automobile steel sheet. However, it is necesarry for its realization to enhance the joint strengh of the steel sheets. In this study, hat-shape components were made by resistance spot welding or arc-spot welding using S45C steel sheet of 1.4mm in thick with strength of 1200MPa grade . Then dynamice three-point bending test was carried out on the components and crashworthiness of them was compared. Absorbed energy of the arc-spot welded component was higher than that of the resistance spot-welded one by 30%. Some spot welds fractured (separated) during the three-point bending test but arc-spot welds did NOT fractured. Arc-spot welding is therefore seemed to be effective to improve strength and toughness of weld for a middle and high carbon steel sheet.
2017-03-28
Technical Paper
2017-01-1272
Nick Parson, Jerome Fourmann, Jean-Francois Beland
One of the main applications for extrusions in the automotive sector is crash structures including crash rails, crash cans, bumpers, and structural body components. The objective is usually to optimize the energy absorption capability for a given structure weight. The ability to extrude thin wall multi-void extrusions contributes to this goal. However, the alloy used also plays a significant role in terms of the ability to produce the required geometry, strength which to a large extent controls the energy absorption capability, and the “ductility” or fracture behavior which controls the strain that can be applied locally during crush deformation before cracking. This paper describes results of a test program to examine the crush behavior of a range of alloys supplied by Rio Tinto Aluminium for automotive applications, as a function of processing parameters including artificial aging and quench rate.
2017-03-28
Technical Paper
2017-01-1471
Xiao Luo, Wenjing Du, Hao Li, Peiyu LI, Chunsheng Ma, Shucai Xu, Jinhuan Zhang
Occupant restraint systems are developed based on some baseline experiments, while these experiments can only represent a small part of various accidents, so the current design of occupant restraint systems cannot provide the optimum protection effects for occupants during the majority of accidents. This study presents an approach to predict occupant injury before the collision happens, so that the occupant restraint system can be adjusted to the optimum parameters aiming at the imminent vehicle-to-vehicle frontal crash. The approach in this study takes advantages of the information from pre-crash systems, such as the time to collision, the relative velocity, the frontal overlap of the ego vehicle during the collision, the size of the vehicle in the front and so on. The information acquired and the basic crash test results can be integrated to predict a simplified crash pulse, and the injury of the occupant in the ego vehicle can thus be predicted using this crash pulse.
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
Journal Article
2017-01-1463
Xianping Du, 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
2017-01-1301
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.
2017-02-16
WIP Standard
AS4694C
Propose revision to add conductive high purity aluminum coating per MIL-DTL-83488 for aluminum alloy fittings. The W code aluminum parts with new finish will be distinguished by new finish code V at the end of part number.
2017-02-16
WIP Standard
AS4808C
SCOPE IS UNAVAILABLE.
2017-02-16
WIP Standard
6533
Fitting will be based on AS4224 except it will specify AS85720 only (5,000 PSI). Related project G3B16-08 will remove "dual" qualification requirements from AS4224 by removing AS85720 and leaving AS85421.
2017-02-16
WIP Standard
6534
Fitting will be based on AS4807 except it will specify AS85720 only (5,000 PSI). Related project G3B16-08 will remove "dual" qualification requirements from AS4807 by removing AS85720 and leaving AS85421.
2017-02-16
WIP Standard
6536
Fitting will be based on AS4808 except it will specify AS85720 only (5,000 PSI). Related project G3B16-08 will remove "dual" qualification requirements from AS4808 by removing AS85720 and leaving AS85421.
2017-02-16
WIP Standard
AS6535
Fitting will be based on AS4809 except it will specify AS85720 only (5,000 PSI). Related project G3B16-08 will remove "dual" qualification requirements from AS4809 by removing AS85720 and leaving AS85421.
2017-02-16
WIP Standard
AS6531
Fitting will be based on AS4221 except it will specify AS85720 only (5,000 PSI). Related project G3B16-08 will remove "dual" qualification requirements from AS4221 by removing AS85720 and leaving AS85421
2017-02-16
WIP Standard
AS6532
Fitting will be based on AS4222 except it will specify AS85720 only (5,000 PSI). Related project G3B16-08 will remove "dual" qualification requirements from AS4222 by removing AS85720 and leaving AS85421.
2017-02-16
WIP Standard
AS6529
Fitting will be based on AS4220 except it will specify AS85720 only (5,000 PSI). Related project G3B16-08 will remove "dual" qualification requirements from AS4220 by removing AS85720 and leaving AS85421.
2017-02-16
WIP Standard
AS6530
Fitting will be based on AS4211 except it will specify AS85720 only (5,000 PSI). Related project G3B16-08 will remove "dual" qualification requirements from AS4211 by removing AS85720 and leaving AS85421.
2017-02-16
WIP Standard
AS6528
Fitting will be based on AS4210 except it will specify AS85720 only (5,000 PSI). Related project G3B16-08 will remove "dual" qualification requirements from AS4210 by removing AS85720 and leaving AS85421.
2017-02-16
WIP Standard
AS4664D
Propose revision to add conductive high purity aluminum coating per MIL-DTL-83488 for aluminum alloy fittings. The W code aluminum parts with new finish will be distinguished by new finish code V at the end of part number.
2017-01-10
WIP Standard
ARP1897A
This document is prepared as an aid in the selection of clamping devices and their use in aerospace equipment for the installation and support of tubing and wiring.
2017-01-10
Technical Paper
2017-26-0017
Celine Adalian, Alba Fornells, Núria Parera
Abstract In the 70’s, to reduce vehicle crash fatalities, NHTSA launched a Program, called NCAP, to compare the safety of cars. This Program was copied in Europe and around the world. It has been demonstrated that this kind of public assessment has forced OEM’s to invest in safety and to develop safer vehicles. Nowadays, NCAPs exist for nearly all regions around the world; all of them with the aim of improving vehicle safety. They apply the philosophy of an “overall rating”. In that way the information aims to be clearer and more general and will help to compare cars. Nevertheless, even though in every NCAP the overall assessment is given by a unique star rating, the specifications and requirements in each protocol are different. Each NCAP has been adapted to each region’s conditions, accidentology and traffic and therefore assessment criteria have their own peculiarities.
2017-01-10
Technical Paper
2017-26-0009
Abhinab Mohanty, Rajasekar Ramaraj, Prashant Dhage, Alok Kumar Ray
Abstract Today’s automotive world has moved towards an age where safety of a vehicle is given the topmost priority. Many stringent crash norms and testing methodology has been defined in order to evaluate the safety of a vehicle prior to its launch in a particular market. If the vehicle fails to meet any of these criteria then it is debarred from that particular market. With such stringent norms and regulations in place it becomes quite important on the engineer’s part to define the structural requirements and protect the space to meet the same. If the concept level platform definition is done properly it becomes very easy to achieve the crash targets with less cost and weight impact.
2017-01-10
Technical Paper
2017-26-0019
Kantilal P. Patil, Viswanatha Saddala
Abstract The objective of this paper is to minimize occupant injuries in offset frontal crash with pulse characterization, by keeping vehicle front crush space & occupant survival space constant. Crash pulse characterization greatly simplifies the representation of crash pulse time histories. The parameters used to characterize the crash pulse are velocity change, time & value of dynamic crush, and zero cross-over time. The crash pulse slope, peaks, average values at discrete time intervals have significant role on occupant injuries. Vehicle crash pulse of different trends have different impact on occupant injury. The intension of crash pulse characterization study is to come out with one particular crash pulse which shows minimum occupant injuries. This study will have significant impact in terms of front loading on crash development of vehicle.
2017-01-09
WIP Standard
AS5117A
No scope available.
2016-11-18
WIP Standard
AS5187A
SCOPE IS UNAVAILABLE.
2016-11-07
Technical Paper
2016-22-0012
Tony R. Laituri, Scott Henry, Kevin Pline, Guosong Li, Michael Frankstein, Para Weerappuli
The National Highway Traffic Safety Administration (NHTSA) recently published a Request for Comments regarding a potential upgrade to the US New Car Assessment Program (US NCAP) - a star-rating program pertaining to vehicle crashworthiness. Therein, NHTSA (a) cited two metrics for assessing head risk: Head Injury Criterion (HIC15) and Brain Injury Criterion (BrIC), and (b) proposed to conduct risk assessment via its risk curves for those metrics, but did not prescribe a specific method for applying them. Recent studies, however, have indicated that the NHTSA risk curves for BrIC significantly overstate field-based head injury rates. Therefore, in the present three-part study, a new set of BrIC-based risk curves was derived, an overarching head risk equation involving risk curves for both BrIC and HIC15 was assessed, and some additional candidate-predictor-variable assessments were conducted. Part 1 pertained to the derivation.
CURRENT
2016-11-01
Standard
J3058_201611
This SAE Recommended Practice describes the dynamic testing procedures required to evaluate the integrity of patient compartment interior Storage Compartments such as cabinets, drawers, or refillable supply pouch systems when exposed to a frontal, side or rear impact (i.e., a crash impact). Its purpose is to provide component manufacturers, ambulance builders, and end-users with testing procedures and, where appropriate, acceptance criteria that, to a great extent, ensure interior Storage Compartments or systems meet the same performance criteria across the industry. Descriptions of the test set-up, test instrumentation, photographic/video coverage, test fixture, and performance metrics are included.
Viewing 1 to 30 of 2152

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