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A BioRID II dummy and a Hybrid III dummy, each representative of a midsize adult male, were tested side-by-side in simulated rear-impact sled tests. In all tests the dummies were restrained by 3-point belt systems. The results of 4 test sets conducted at a nominal change in velocity (ΔV) of 16 km/hr are presented and discussed. In three of the test sets, bucket seats were used. The head restraints were placed in the up-position in two of the three test sets and in the down-position in the third set of tests. In the fourth test set, rigid seats without any head restraints were used. While analyzing the BioRID II data, the presence of an axial neck load acting on the head, which bypassed the upper neck load transducer, was discovered in all the reported tests. The implication of this observation is that the axial force and all the moments measured by the BioRID II upper neck load transducer could be erroneous.

The THUMS (Total HUman Model for Safety) 3-year-old child finite element (FE) model was developed by Toyota Central R&D Labs (TCRDL) by model-based scaling from the AM50 (50 percentile male) human FE model. The objective of this paper is to present a comparison between the kinematics of a child FE model developed from the adult THUMS model and a HYRID III 3-year-old child dummy using observations from numerical simulations of a CMVSS 208 frontal crash. Both the child models were positioned in a forward facing, five point child restraint systems (CRS). An acceleration pulse acquired from a vehicle crash test in accordance with Canadian Motor Vehicle Safety Standards (CMVSS) 208 was applied to the seat buck supporting the CRS. Numerical simulations with both the child model and the Hybrid III child dummy were conducted using LS-DYNA version 970.

In order to evaluate the THOR-50M as a front impact Anthropomorphic Test Device (ATD) for vehicle safety design, the ATD was compared to the H3-50M in matching vehicle crash tests for 20 unique vehicle models from 2 vehicle manufacturers. For the belted driver condition, a total of fifty-four crash tests were investigated in the 56.3 km/h (35 mph) front rigid barrier impact condition. Four more tests were compared for the unbelted driver and right front passenger at 40.2 km/h (25 mph) in the flat frontal and 30-degree right oblique rigid barrier impact conditions. The two ATDs were also evaluated for their ability to predict injury risk by comparing their fleet average injury risk to Crash Investigation Sampling System (CISS) accident data for similar conditions. The differences in seating position and their effect on ATD responses were also investigated.

The National Highway Traffic Safety Administration (NHTSA) and the Insurance Institute for Highway Safety (IIHS) have both developed crash test methodologies to address frontal collisions in which the vehicle's primary front structure is either partially engaged or not engaged at all. IIHS addresses Small Overlap crashes, cases in which the vehicle's primary front energy absorbing structure is not engaged, using a rigid static barrier with an overlap of 25% of the vehicle's width at an impact angle of 0°. The Institute's Moderate Overlap partially engages the vehicle's primary front energy absorbing structure using a deformable static barrier with 40% overlap at a 0° impact angle. The NHTSA has developed two research test methods which use a common moving deformable barrier impacting the vehicle with 20% overlap at a 7° impact angle and 35% overlap at a 15° impact angle respectively.

Problems with the current methods of attaching child restraints to the vehicle structure have led to the development of new attachment systems. These proposals have been coordinated by the International Standards Organisation (ISO) with the intention of generating an international standard system for the attachment of child restraints - ISOFIX. These proposals attempt to balance the requirements for good dynamic performance in impacts with the requirements for ease of use, low misuse and the cost and complexity of the child restraint and of incorporating the system into the vehicle design. This research programme was designed to compare the dynamic performance of a range of systems and how they would be used by parents. Prototype child restraints designed to four different schemes being proposed for ISOFIX were produced based on a single design of child seat shell. These were subject to frontal, side and rear impacts.

It is often said that heavier cars are inherently safer than lighter ones. However, when all cars are built with steel, larger size necessarily implies greater weight, so it is unclear whether the improved safety correlates to the weight or size of the vehicle. Using a publicly available computer model of the Ford Taurus, it was thought that this perception could be tested. The existing steel model, with the addition of a Hybrid III dummy and driver side airbag, was validated against actual crash test data. The structure was converted to aluminum, structural stiffness was calculated, and the steel and aluminum crash simulation results were compared. The aluminum model, utilizing monocoque sheet structure, weld bonded joining, and tailor welded blanks, weighed 200 kg less than the steel model and performed as well.

This is the first paper in a new series to present a coherent theory of sensing frontal crashes, define the characteristics of future airbag sensor systems and to present examples of how this theory can be implemented. After summarizing the relevant conclusions from the authors' previous papers, this paper concludes that future systems should contain: crush zone sensors which sense relevant impacts to all portions of the vehicle front; an occupant position sensor as an input to the sensing system; and a mechanical safing/arming sensor having a long dwell. It is further concluded that cars should be designed so that only impacts involving the front of the vehicle need be sensed for the deployment of frontal protection airbags. This series of papers has the main goal of determining an overall theory of frontal crash sensing and the resulting desirable properties of sensor systems. A second goal is to give examples of how this theory can be realized in real sensor systems.

Described in this paper is a component test methodology to evaluate the door trim armrest performance in an Insurance Institute for Highway Safety (IIHS) side impact test and to predict the SID-IIs abdomen injury metrics (rib deflection, deflection rate and V*C). The test methodology consisted of a sub-assembly of two SID-IIs abdomen ribs with spine box, mounted on a linear bearing and allowed to translate in the direction of impact. The spine box with the assembly of two abdominal ribs was rigidly attached to the sliding test fixture, and is stationary at the start of the test. The door trim armrest was mounted on the impactor, which was prescribed the door velocity profile obtained from full-vehicle test. The location and orientation of the armrest relative to the dummy abdomen ribs was maintained the same as in the full-vehicle test.

A recent study of U.S. crash data has shown that children 0-23 months of age in forward-facing child restraint systems (FFCRS) are 76% more likely to be seriously injured in comparison to children in rear-facing child restraint systems (RFCRS). Motivated by the epidemiological data, seven sled tests of dummies in child seats were performed at the University of Virginia using a crash pulse similar to FMVSS 213 test conditions. The tests showed an advantage for RFCRS; however, real-world crashes include a great deal of variability among factors that may affect the relative performance of FFCRS and RFCRS. Therefore, this research developed MADYMO computational models of these tests and varied several real-world parameters. These models used ellipsoid models of Q-series child dummies and facet surface models of American- and Swedish- style convertible child restraints (CRS).

A computer simulation method for motorcycle rider motion in a collision on a passenger car has been developed. The computer simulation results were in two cases of collision, at 45 degree and 90 degree angles against the side of a passenger car. The simulated results were compared to the test results for validation. The simulation software of explicit finite element method (FEM) has been used, because of its capability for expressing accurate shape and deformation. The mesh size was determined with consideration for simulation accuracy and calculation time, and an FEM model of a motorcycle, an airbag, a dummy, a helmet and a passenger car were built. To shorten the calculation time, a part of the model was regarded as a rigid body and eliminated from the contact areas. As a result, highly accurate dummy posture and head velocity at the time of contact on the ground were simulated in the two cases of collision.

Impositions placed on vehicle occupants by safety belts and safety belt use are substantial and will increase as systems to encourage or force belt usage are incorporated. By comparison, the known impositions of air bags are minor, but to these must be added other requirements, the extent of which are not yet well-known. Substantial fleet testing of air bags will clarify most of these inconveniences. Automobile manufacturers and the National Highway Traffic Safety Administration have failed to generate public support for the air bag. Lack of consumer support will continue unless greater resources are allocated to equip fleet vehicles with air bag systems so that a reliable record of air-bag efficacy can be compiled.

Lap-shoulder belts became standard with very little, very inneffective explanation of why they should be used. National effort is needed to persuade all to use them, and auto industry to improve them, and see the effect of buzzers and interlocks before mandating airbags or equivalent. This paper looks at the past history of restraints, forecasts the future if airbags are to be mandated without explaining them. AAA of Michigan motorist survey shows strong dislike of airbags, a preference for seatbelt-shoulder harness if choice must be made, a strong feeling that it is not the business of government to mandate airbag or seatbelt use. Question is raised about claims of number of lives that airbags will save. Are they too high?

The integrated correlation methodology is applied to the correlation of the airbag body block test and the component tests of sub systems consisting of the steering control system. By using the optimization technique for the occupant simulation model involving two-dimensional curves as the input, the optimal scale factors of the input F-D curves are found in order to minimize the sum of deviations between simulation and test results. In addition, the optimal one-dimensional unknown inputs that can't be obtained by component tests are found. It is found that the optimization technique used in this study is very suitable for the correlation of the occupant simulation model that has 2-dimensional test input data, and it is able to shorten the entire correlation time and ensure the reliability of the correlation result. This correlation methodology can be applied to the sled test and the barrier test for validating the occupant analysis model.

This paper reports the analytical procedure developed for a simulation of knee impact during a barrier crash using a hybrid III dummy lower torso. A finite element model of the instrument panel was generated. The dummy was seated in mid-seat position and was imparted an initial velocity so that the knee velocity at impact corresponded to the secondary impact velocity during a barrier crash. The procedure provided a reasonably accurate simulation of the dummy kinematics. This simulation can be used for understanding the knee bolster energy management system. The methodology developed has been used to simulate impact on knee for an occupant belted or unbelted in a frontal crash. The influence of the vehicle interior on both the dummy kinematics and the impact locations was incorporated into the model. No assumptions have been made for the knee impact locations, eliminating the need to assume knee velocity vectors.

A low cost and low speed automobile crash test facility for full frontal impacts has been designed and constructed to determine vehicle crush characteristics. The function and operation of systems comprising the facility are discussed in this paper and include: Site layout and tow system arrangement Tow system and test vehicle guidance Crash barrier Release mechanisms Speed measurement Recording of the impact event In addition, the crash barrier is validated with preliminary test results.

An evaluation methodology has been developed for assessing the suitability of R-1234yf in vehicles. This relates primarily to evaluating the flammability of R-1234yf in the engine compartment during a frontal collision. This paper will discuss the process followed in the methodology, the technical rationale for this process, and the results of the analysis. The specific types of analysis included in the methodology are: exhaust-system thermal characterization, computer simulated crash tests, actual crash tests, teardown and examination of crashed parts, and releases of refrigerant onto hot exhaust manifolds. Each type of analysis was logically ordered and combined to produce a comprehensive evaluation methodology. This methodology has been applied and demonstrates that R-1234yf is difficult to ignite when factors that occur in frontal crashes are simultaneously considered.

In two previous SAE papers (1,2) by the authors, supporting analysis was presented showing the difficulty in achieving a timely response to real-crash events using a single point sensor mounted in the non-crush zone of the vehicle (tunnel, cowl, etc.). The analysis demonstrated the propensity to deploy the air bag(s) late during certain of these events. If a vehicle occupant was not wearing a safety belt, the deceleration forces of the crash could place the occupant out of position and resting against the air bag when it was deployed. In another SAE paper (3) by H. J. Mertz et al, the authors demonstrated that animals, used as surrogates for humans, could be injured if positioned against an air bag at the time of deployment. Arguments are presented here to show that there is insufficient information in the crash pulse as sensed in the non-crush zone to deploy an air bag in time for the unbelted occupant.

A simple spring-mass model of the impact response of the side impact dummy (SID) is established. The spring and mass constants of the model are established through system identification methodology based on data from impact tests. The tests are performed in laboratory with hydraulically driven impactors impacting the chest and pelvis of the SID. The input data to the model consist of measured contact force or impactor velocity time histories, and the output data are accelerations on the rib, spine, and pelvis of the SID. The established model appears to predict the test results with reasonable accuracy. The main purpose of this study, however, is to use this simple model to carry out parametric studies of the response of the dummy with changing impact parameters, the result of which would be useful in understanding vehicle crash tests using the SID.

The FMVSS 201 regulation requires that interior components in upper compartment of a passenger vehicle pass a head impact test using a Free Moving Head (FMH) model with a HIC(d) limit. In this type of test, most interior components themselves do not generate high HIC(d) numbers but the steel structures underneath these components do. In addition to normal functions, interior components need to absorb the kinetic energy of the FMH model such that the acceleration response of the FMH model does not generate a high HIC(d) number in the test. This paper first reviews the existing work on the principles for the head impact protection and identifies limitations of the existing theory for the design of the interior components that are mounted on flexible structures. This paper discusses and proposes a design methodology for automotive interior components to ensure that they comply with FMVSS 201 head impact requirements.

A recently developed angular motion sensor, based on the laws of magnetohydrodynamics, has potential application in biodynamic research and was tested on the Naval Biodynamics Laboratory's (NBDL) horizontal accelerator, using the Hybrid III manikin as the test subject. The sensors in question were used to measure the manikin's head motion in three dimensions. Experiments were conducted at levels up to 25g in the frontal and oblique impact configurations, and included both indirect impact (no head contact) and direct impact of the head into a simulated windshield. Data collection was performed utilizing both narrowband (125 Hz) and wideband (1000 Hz) channels. The analyses of the tests show that the new sensor compared very well with two different configurations of the 9-accelerometer arrays commonly used in impact testing. The comparisons were made at both the acceleration and velocity levels.