Evaluation of Automotive Roof Strength and Pretensioner Performance on the Occupant Neck Load

2010 ◽  
Author(s):  
Chandrashekhar K. Thorbole ◽  
Stephen A. Batzer ◽  
David A. Renfroe
Keyword(s):  
Traffic Safety ◽  
Injury Risk ◽  
Element Model ◽  
Neck Injury ◽  
Highway Traffic ◽  
National Highway Traffic Safety ◽  
Hybrid Iii ◽  
The Subject ◽  
Roof Strength ◽  
Modest Level

Roof intrusion is a major cause of neck injury to belted occupants during rollover accidents. The correlation of reduced head room with increased injury risk has been demonstrated by the National Highway Traffic Safety Administration (NHTSA) and others such as the Insurance Institute of Highway Safety (IIHS). The current FMVSS 216 standard requires the vehicle roof, when loaded with a platen of prescribed geometry and application vector, to resist 1.5 times the vehicle empty weight before deforming 127mm. This standard was developed to ensure a modest level of safety of the vehicle in rollover. This paper demonstrates the relation between roof intrusions, available head room and belt pretension on occupant neck loads. A validated finite element model of a 2001 Ford Taurus is used to conduct an inverted drop simulation. The vehicle’s roof impacts an ideally rigid surface with 5 deg of roll and 10 deg of pitch. A 95th percentile Hybrid III ATD (Anthropomorphic Test Device) is used to simulate a large occupant. The simulations are conducted both for a production roof and a modified stiffer, stronger roof. The production roof is modified by addition of extra material in the B-pillars and A-pillars to enhance strength. A seatbelt pretensioner is also modeled to demonstrate the effectiveness of belt pretension in attenuating neck loads. This study demonstrates the inadequate performance of the subject production roof in preventing neck injury. The stronger roof in association with the belt pretensioner reduces the magnitude of the neck loads sufficiently to prevent injury. This study indicates that strong, non-deforming roofs along with belt pretension diminishes neck injury.

Designing for Rollover Impacts With Narrow Objects

2011 ◽  
Author(s):  
Brian R. Herbst ◽  
Steven E. Meyer ◽  
Arin A. Oliver ◽  
Lauren D. Bell ◽  
Stephen M. Forrest
Keyword(s):  
Traffic Safety ◽  
High Speed ◽  
The United States ◽  
Tilt Test ◽  
Highway Traffic ◽  
Test Device ◽  
National Highway Traffic Safety ◽  
Roof Structure ◽  
Occupant Injury ◽  
Roof Strength

While some debate has existed in the literature regarding the relationship between roof crush and occupant injury, the United States (U.S.) National Highway Traffic Safety Administration (NHTSA) has identified an increased safety benefit in improving roof strength and has mandated new higher roof crush resistance requirements. Frequently, roof impacts occur in rollover crashes when a vehicle travels off the lanes of the roadway and impacts various types of narrow objects along the roadway edge such as light poles, utility poles and/or trees. A previously reported tilt-test device and methodology is presented along with a new pendulum-test device and methodology, both of which allow for dynamic, repeatable impact evaluation of vehicle roof structures with narrow objects. The data collected includes not only residual crush, but also dynamic vehicle instrumentation and high speed video analysis. Two series of full vehicle tests are reported which represent each of the methodologies. The testing conditions for each series was determined based upon analysis of a real-world narrow object rollover impact. Each testing series allows for analysis of the damage resulting from the narrow object impact to the roof structure for a production vehicle as well as one that has been structurally reinforced. Results demonstrate that the reinforced roof structure significantly reduced the roof deformation compared to that of the production roof structure. The input energy of each test and resulting damage patterns can be used as both a reconstruction tool and structural assessment test.

Preliminary Calibration and Validation of a Finite Element Model of THOR Mod Kit Dummy

2014 ◽  
Author(s):  
Costin D. Untaroiu ◽  
Jacob B. Putnam ◽  
Jeffrey T. Somers ◽  
Joseph A. Pellettiere
Keyword(s):  
Finite Element ◽  
Traffic Safety ◽  
Element Model ◽  
Crash Test ◽  
Fe Model ◽  
Loading Conditions ◽  
Highway Traffic ◽  
National Highway Traffic Safety ◽  
Spinal Loading ◽  
Safety Standards

New vehicles are currently being developed to transport crews to space by NASA and several commercial companies. During the takeoff and landing phase, vehicle occupants are typically exposed to spinal and frontal loading. To reduce the risk of injuries during these common impact scenarios, NASA has begun research to develop new safety standards for spaceflight. The THOR, an advanced multi-directional crash test dummy, was chosen by NASA to evaluate occupant spacecraft safety due to its improved biofidelity. Recently, a series of modifications were completed by the National Highway Traffic Safety Administration (NHTSA) to improve the bio-fidelity of the THOR dummy. The updated THOR Modification Kit (THOR-K) dummy was tested at Wright-Patterson (WP) Air Base in various impact configurations, including frontal and spinal loading. A computational finite element (FE) model of the THOR was developed in LS-DYNA software and was recently updated to match the latest dummy modifications. The main goal of this study was to calibrate and validate the FE model of the THOR-K dummy for use in future spacecraft safety studies. An optimization-based method was developed to calibrate the material properties of the pelvic flesh model under quasi-static and dynamic loading conditions. Data in a simple compression test of pelvic flesh were used for the quasi-static calibration. The whole dummy kinematic and kinetic response under spinal loading conditions was used for the dynamic calibration. The performance of the calibrated dummy model was evaluated by simulating a separate dummy test with a different crash pulse along the spinal direction. In addition, a frontal dummy test was also simulated with the calibrated model. The model response was compared with test data by calculating its correlation score using the CORA rating system. Overall, the calibrated THOR-K dummy model responded with high similarity to the physical dummy in all validation tests. Therefore, confidence is provided in the dummy model for use in predicting response in other test conditions such as those observed in the spacecraft landing.

Study of Occupant Safety and Airbag Deployment Time

2015 ◽  
Author(s):  
Steven Yang ◽  
Kristian Lardner ◽  
Moustafa El-Gindy
Keyword(s):  
Traffic Safety ◽  
Impact Test ◽  
Crash Test ◽  
Passenger Vehicle ◽  
Highway Traffic ◽  
Element Analysis ◽  
National Highway Traffic Safety ◽  
Hybrid Iii ◽  
Airbag Deployment ◽  
Deployment Time

This paper presents the use of Finite Element Analysis (FEA) software in recreating a full frontal barrier impact test with a 50th percentile male hybrid III dummy to investigate various passenger vehicle airbag deployment times for the development of an airbag trigger sensor. Results for the physical full frontal barrier impact test where prepared by MGA Research Corporation with a 2007 Toyota Yaris. Using a nonlinear transient dynamic FEA software, a virtual full frontal barrier impact test was created to reproduce the physical results and trends experienced in the physical crash test found in a report by the National Highway Traffic Safety Administration (NHTSA) 5677. The results of the simulation were compared to the results of the physical crash which produced similar trends, but not the same values. The simulation was then used in testing different passenger vehicle airbag deployment times to see its results on specific occupant injury criteria’s; Head Injury Criterion (HIC), Chest Compression Criterion (CC). Four different vehicle speeds where used; 20 km/h, 40 km/h, 56 km/h, and 90 km/h in conjunction with a range of +/− 6 milliseconds in the airbag deployment timing. Results of the airbag deployment timing showed that trends of faster airbag deployment times resulted in lower values for HIC and CC. Following these trends, suggestions for airbag deployment trigger distances were developed to aid in creation of an advanced airbag deployment sensor or crash sensor. While the simulation has yet to be validated, the trends may be assessed and actual values may differ.

Roof Strength: A Factor in Rollover Injuries

2000 ◽  
Author(s):  
Stephen R. Syson
Keyword(s):  
Traffic Safety ◽  
Relative Frequency ◽  
Reporting System ◽  
Highway Traffic ◽  
Passenger Cars ◽  
National Highway Traffic Safety ◽  
Light Trucks ◽  
Roof Strength ◽  
Involvement Rate ◽  
Serious Injuries

Abstract Recently, the National Highway Traffic Safety Administration (NHTSA) reported that injuries and fatalities in rollover continue to be a serious problem out of proportion with the relative frequency of such incidents. (Summers, 1997) On average, 7,797 annual rollover involved fatalities were reported by the Fatal Accident Reporting System (FARS), between 1988 and 1994. There were also between 43,000 and 58,000 annual rollover involved incapacitating injuries between 1988 and 1994, as reported by NASS GES. Approximately 16 percent of serious injuries to passenger car occupants and 42 percent of serious injuries to light truck occupants occurred in vehicles that rolled over. Light trucks, including vans, experienced the highest rollover involvement rate, 25.9 percent, compared to 15.3 percent for passenger cars.

A Commented Synopsis of the Report of the Committee for the National Tire Efficiency Study4

2007 ◽  
Vol 35 (2) ◽  
pp. 70-93
Author(s):  
Marion G. Pottinger ◽  
Joseph D. Walter ◽  
John D. Eagleburger
Keyword(s):  
Traffic Safety ◽  
Rolling Resistance ◽  
The United States ◽  
Final Report ◽  
Highway Traffic ◽  
National Academy Of Sciences ◽  
Scrap Tire ◽  
National Highway Traffic Safety ◽  
Fuel Savings ◽  
Time Required

Abstract The Congress of the United States petitioned the Transportation Research Board of the National Academy of Sciences to study replacement passenger car tire rolling resistance in 2005 with funding from the National Highway Traffic Safety Administration. The study was initiated to assess the potential for reduction in replacement tire rolling resistance to yield fuel savings. The time required to realize these savings is less than the time required for automotive and light truck fleet replacement. Congress recognized that other factors besides fuel savings had to be considered if the committee’s advice was to be a reasonable guide for public policy. Therefore, the study simultaneously considered the effect of potential rolling resistance reductions in replacement tires on fuel consumption, wear life, scrap tire generation, traffic safety, and consumer spending for tires and fuel. This paper summarizes the committee’s report issued in 2006. The authors, who were members of the multidisciplinary committee, also provide comments regarding technical difficulties encountered in the committee’s work and ideas for alleviating these difficulties in further studies of this kind. The authors’ comments are clearly differentiated so that these comments will not be confused with findings, conclusions, and recommendations developed by the committee and contained in its final report.

Distribution of Speed and Acceleration on a Tread Wear Course

1981 ◽  
Vol 9 (1) ◽  
pp. 19-25 ◽  
Author(s):  
G. S. Ludwig ◽  
F. C. Brenner
Keyword(s):  
Traffic Safety ◽  
Highway Traffic ◽  
National Highway Traffic Safety ◽  
Level Crossings ◽  
Acceleration Level ◽  
Longitudinal Acceleration ◽  
Acceleration Data ◽  
National Highway

Abstract Belted bias and radial Course Monitoring Tires were run over the National Highway Traffic Safety Administration tread wear course at San Angelo on a vehicle instrumented to measure lateral and longitudinal accelerations, speed, and number of wheel rotations. The data were recorded as histograms. The distribution of speed, the distributions of lateral and longitudinal acceleration, and the number of acceleration level crossings are given. Acceleration data for segments of the course are also given.

The Analysis and Assessment of Test Method for Flammability of an Automotive Headlining Fabric

2011 ◽  
Vol 332-334 ◽  
pp. 1162-1166
Author(s):  
Zhuo Zhang ◽  
Ying Qing Liu ◽  
Zhong Hai Ren ◽  
Jia Zhuang Ma ◽  
Hu Shui Ye
Keyword(s):  
Traffic Safety ◽  
Test Method ◽  
Highway Traffic ◽  
National Highway Traffic Safety ◽  
Test Standards ◽  
Foreign Countries ◽  
Mandatory Standard ◽  
Testing Standards ◽  
Interior Textile ◽  
Automotive Interior

The flammability is one of the most important features about safety for automotive interior material. This paper summarized the testing standards for flammability performed testing on a type of interior textile material made by one of domestic manufacturers, in accordance with the Chart 571.302 Standard No. 302 of the National Highway Traffic Safety Administration of U.S. The complete introduction of national mandatory standard of China in flammability of interior material was introduced and domestic test standards of flammability with those of foreign countries all over world were compared. Finally, this paper proposed possible and would-be necessary parameters based on comprehensiveness of this kind of test due to safer requirement in future.

Sign in / Sign up

Export Citation Format

Share Document