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Locations of key body segments of Hybrid III dummies used in FMVSS 208 compliance tests and NCAP tests were measured and subjected to statistical analysis. Mean clearance dimensions and their standard deviations for selected body segments of driver and passenger occupants with respect to selected vehicle surfaces were determined for several classes of vehicles. These occupant locations were then investigated for correlation with impact responses measured in crash tests and by using a three dimensional human-dummy mathematical model in comparable settings. Based on these data, the importance of some of the clearance dimensions between the dummy and the vehicle surfaces was determined. The study also compares observed Hybrid III dummy positions within selected vehicles with real world occupant positions reported in published literature.

During frontal and rear end type collisions, very large forces will be imparted to the passenger compartment by the collapse of either front or rear structures. NCAP tests conducted by NHTSA involve, among other things, a door openability test after barrier impact. This means that the plastic/irreversible deformations of door openings should be kept to a minimum. Thus, the structural members constituting the door opening must operate during frontal and rear impact near the elastic limit of the material. Increasing the size of a structural member, provided the packaging considerations permit it, may prove to be counter productive, since it may lead to premature local buckling and possible collapse of the member. With the current trend towards lighter vehicles, recourse to heavier gages is also counterproductive and therefore a determination of an optimum compartment structure may require a number of design iterations. In this article, FEA is used to simulate front side door behavior.

Injury to the thorax is the predominant cause of fatalities in crash-involved automobile occupants over the age of 65, and many elderly-occupant automobile fatalities occur in crashes below compliance or consumer information test speeds. As the average age of the automotive population increases, thoracic injury prevention in lower severity crashes will play an increasingly important role in automobile safety. This study presents the results of a series of sled tests to investigate the thoracic deformation, kinematic, and injury responses of belted post-mortem human surrogates (PMHS, average age 44 years) and frontal anthropomorphic test devices (ATDs) in low-speed frontal crashes. Nine 29 km/h (three PMHS, three Hybrid III 50th% male ATD, three THOR-NT ATD) and three 38 km/h (one PMHS, two Hybrid III) frontal sled tests were performed to simulate an occupant seated in the right front passenger seat of a mid-sized sedan restrained with a standard (not force-limited) 3-point seatbelt.

The paper describes the use of strain gauge goniometers to measure dummy leg joint angles in impact tests. The instruments have been developed based on regular goniometers used for human gait analysis. Specific modifications enhanced the mechanical stability and the electrical insulation of the sensors. They are now compatible with standard crash data acquisition systems. Several vehicle crash tests have been analyzed using the goniometers as a supplementary measurement device. Due to its low weight, the device does not significantly alter the dummy behavior. Further areas of application are outlined in the paper.

One of the major goals in the design of the new Ford Aeromax and Louisville heavy truck product line was to achieve competitive leadership in visibility. Market research found that visibility was an important issue to the heavy truck driver. Visibility is defined as both direct and indirect (i.e., the driver's ability to see with and without the use of supplemental vision devices such as mirrors) and both interior and exterior. The scope of this paper includes the work which was accomplished in evaluating direct and indirect exterior visibility and the resulting vehicle design which achieved Ford's leadership goals. Poor weather visibility and interior vision are beyond the scope of this paper. Polar Plots were the method of choice in the Aeromax/Louisville visibility studies. Industry acceptance of these techniques has been established in the recent approval of SAE J1750, “Evaluating the Truck Driver's Viewing Environment”.

The influence of calcium treatment on the mechanical properties of a plain carbon steel (SAE 1050) was investigated. The mechanical properties investigated were tensile and impact strength, fatigue crack growth rate, and the fatigue threshold. Impact testing was conducted at both room temperature and at -40°C. Several heats of both calcium and non-calcium treated steel (SAE 1050) were tested in both the as hot-rolled condition and in the quenched and tempered condition (with a hardness level of HRC = 45). The results of this investigation show no significant difference in the tensile properties or room temperature impact properties between the calcium treated and the non-calcium treated steels. However, the impact strengths of calcium treated steels were slightly higher than that of non-calcium treated steels at -40°C.

The SAE Recommended Practice J963 “Anthropomorphic Test Device for Dynamic Testing” describes a standard 50th percentile adult male anthropomorphic test dummy. For nearly three years the Crash Test Dummy Task Force worked with the limited data available in selecting values for the body dimensions and ranges of motion. The data for specifying the values of mass distribution were developed experimentally as was a test procedure for determining the dynamic spring rate of the thorax.

Consider this recent data about the "speed'' of the information age: In a sixty-month window beginning in the year 1995, the number of cellular phone subscribers increased from 90 million to 330 million, the number of people on the internet went from about 5 million to just under 200 million, and not surprisingly the number of websites grew from a few thousands to 50 million. Now further consider that almost every cellular phone subscriber is also an automobile user, be it as a driver or a passenger. A fabric of mobility soon emerges --- one that is formed by the meshing of the strands of information mobility with those of personal mobility. In this paper we explore a "new frontier'' --- a "territory'' on this multidimensional fabric that is defined by the demands of seamless mobility. The typical daily cycle of events in our lives involve many different modalities and time-phases of mobility. We examine the rapidly increasing demands of seamless mobility in this context.

STYLING the Continental Mark II with a very low silhouette without sacrificing leg room, seating comfort, and driver visibility was accomplished by using a specially designed frame and a 3-joint driveline. These two features are the basic engineering innovations which make possible the Continental's distinctive classic styling. As a result of this structural analysis, Ford has produced an automobile that, according to the author, has technical advancements that are of value to the consumer.

The European safety regulation plan regarding frontal barrier offset impact calls for 30° angular impact protection in 1995 and a perpendicular 40% offset deformable barrier impact protection in the 1998 time frame. However, various other governmental and private agencies are looking at alternative test conditions. The Auto Motor and Sport Magazine and other insurance agencies have been conducting rigid barrier front impact tests at 40 and 50% offsets. In this study various test conditions were examined analytically. Detailed finite element models were developed to understand the implications of these impact conditions. The models provided insight into energy management mechanism, load transfer and vehicle deformation patterns due to offset impacts on to perpendicular and angular barriers. Several potential offset conditions were simulated using the FEA models.

Seatback strength and injury potential in moderate to high-speed rear-end collisions were investigated in a series of 12 HYGE sled tests. The test methodology included the use of instrumented Hybrid-III anthropomorphic test devices (ATDs). Four tests employed a 95th percentile male ATD ballasted to a total weight of 300 lbs and subjected to approximate 15 mph Delta-V impacts. The remaining tests employed an unmodified 50th percentile male ATD with impacts of approximately 25 mph Delta-V, and three ATD positions, including two "out of position" postures corresponding to leaning forward ("forward" position), and leaning forward and inboard ("radio" position). Seats from three different vehicles were tested, representing a range of strength values. Upper neck values for N were less than 1.0 in all cases. Lower neck N values sometimes exceeded 1.0 with the 50th percentile male ATD out of position, and these values did not trend with seatback strength.

While evaluating the BIOSID advanced side impact dummy in full scale crash tests, we noticed higher than expected abdominal rib deflections. This finding led to a search to determine whether these deflections were an artifact of the dummy or whether the dummy was indicating that some portion of the vehicle side, in the area of the armrest, was laterally stronger than expected. Many armrests/trim panels were procured and both quasi-statically and dynamically tested using newly-devised test procedures. A team was formed to evaluate armrest/trim panel construction and to develop a biomechanically-based laboratory test procedure to help determine the effects of design and material changes. This team continues to function and a spin-off team is seeking to develop analytical predictive tools to allow speedier development of armrest/trim panels attuned to the new test procedure.

This presentation proposes an approach to use ABS wheel speed sensor signals together with other vehicle state information from a brake control module to detect an unbalanced tire or tires in real-time. The proposed approach consists of two-stage algorithms that mix a qualitative method using band-pass filtering with a quantitative parameter identification using conditional least squares. This two-stage approach can improve the robustness of tire imbalance or imbalances. The proposed approach is verified through vehicle testing and the test results show the effectiveness of the approach. Presenter Jianbo Lu, Ford Motor Co.

Vehicle side impact performance is potentially affected by a large number of parameters which may be related to body stiffness and energy absorption characteristics, and packaging dimensions. An understanding of the principal variables controlling TTI (Thoracic Trauma Index) is fundamental to the achievement of high LINCAP (Lateral Impact New Car Assessment Program) rating especially for sedans. In the present study, the effects on TTI of the following are considered: response-related parameters such as velocity and intrusion (which are in turn related to body structure), countermeasures such as side airbag, and dummy to structure clearance dimensions. With the help of test data gathered from side impact tests carried out on cars and trucks at Ford, a new “best subset” regression model is developed and is shown to be able to predict TTI for a number of LINCAP tests which were not part of the suite used in the derivation of the model.

Two rigid rollover test devices were constructed to have the approximate dimensions, mass and inertial properties of a mid-sized Car and Sport Utility Vehicle (SUV). The rigid devices were used to generate vehicle and occupant responses from a series of laboratory rollover tests. For each rigid rollover test, a deceleration sled was used to subject each rigid vehicle to nearly identical lateral speeds and decelerations. The rigid vehicles were limited to a single roll by tethering the vehicles to the deceleration cart. The vehicle's roll rate, roll angle, lateral acceleration and Anthropomorphic Test Devices (ATD) neck responses generated from the rigid SUV were compared to the responses of a full vehicle production SUV under similar test conditions. The rigid SUV and Car devices were then used to examine the effects of activating safety belt pre-tensioning systems and roof mounted side curtain airbags at various times on ATD neck forces and moments.

Having, by now, introduced several new vehicles that comply with FMVSS 202a, manufacturers are reporting an increased number of complaints from consumers who find that the head restraint is too close; negatively affecting their posture. It is speculated that one of the reasons that head restraints meeting the new requirement are problematic is that the FMVSS backset measurement is performed at a back angle that is more reclined than the back angle most drivers choose and the back angle at which the seat / vehicle was designed. The objective of this paper is to confirm this hypothesis and elaborate on implications for regulatory compliance in FMVSS 202a.

This paper provides a methodology for adjustment of off-speed head impact test data to the required 24.14 km/h for interior head impact. The “Normalization Process” utilizes the Generic Waveform Concept for its basic foundation. Predicted results from FE Head Impact Simulation Model were used to validate the Normalization Process. It is recommended that Normalization should be applied to cases where impact velocities are within ±0.8 km/h speed difference. In general, Normalizing down-speed (from 24.94 to 24.14 km/h) is preferred over Normalizing up-speed (23.33 to 24.14 km/h). One must always check for potentially severe “bottom-out” condition by examining the pulse shape for any abrupt peaks in headform deceleration. The Normalization Process should not be applied to “glancing” impacts in which the impact and rebound vectors are not colinear.

This book draws upon a variety of the author's experiences during more than 25 years in automotive safety. It gives an introduction to plain film radiographs (x-rays), computed tomograms (CTs), and magnetic resonance images (MRIs) such that vehicle safety professionals can use these techniques to help piece together the puzzle and provide a better understanding of the relationship between vehicle crash scenarios and occupant injury. For those with a primarily vehicle background, Neck Injury provides an overview of how x-rays, CTs, and MRIs may be used as a source of information to help analyze vehicle crashes and the associated injuries. For those with a clinical background, the book provides insight into how injuries relate to the vehicle crash. Chapters cover: Anatomy Imaging Injuries and Injury Mechanisms

A highly controlled six-vehicle crash test program was conducted to provide an estimate of the test-to-test variability of the NHTSA-proposed passenger car dynamic side impact test procedure. The results of this program showed that the rear seat test dummy response measurements are especially sensitive to various parameters of the test procedure. This paper provides estimates of front and rear seated SID dummy response measurement variability in four-door, 1990 Ford Taurus vehicles. Conclusions and recommendations from this controlled crash test program are made to provide guidance to help reduce the test-to-test variability of the test dummy responses.

This paper presents the final phase of a study to develop the modeling methodology for an advanced steering assembly with a safety-enhanced steering wheel and an adaptive energy absorbing steering column. For passenger cars built before the 1960s, the steering column was designed to control vehicle direction with a simple rigid rod. In severe frontal crashes, this type of design would often be displaced rearward toward the driver due to front-end crush of the vehicle. Consequently, collapsible, detachable, and other energy absorbing steering columns emerged to address this type of kinematics. These safety-enhanced steering columns allow frontal impact energy to be absorbed by collapsing or breaking the steering columns, thus reducing the potential for rearward column movement in severe crashes. Recently, more advanced steering column designs have been developed that can adapt to different crash conditions including crash severity, occupant mass/size, seat position, and seatbelt usage.