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NASA is developing a new crewed vehicle and desires a lower risk of injury compared to automotive or commercial aviation. Through an agreement with the National Association of Stock Car Auto Racing, Inc. (NASCAR®), an analysis of NASCAR impacts was performed to develop new injury assessment reference values (IARV) that may be more relevant to NASA's context of vehicle landing operations. Head IARVs associated with race car impacts were investigated by analyzing all NASCAR recorded impact data for the 2002-2008 race seasons. From the 4015 impact files, 274 impacts were selected for numerical simulation using a custom NASCAR restraint system and Hybrid III 50th percentile male Finite Element Model (FEM) in LS-DYNA. Head injury occurred in 27 of the 274 selected impacts, and all of the head injuries were mild concussions with or without brief loss of consciousness. The 247 noninjury impacts selected were representative of the range of crash dynamics present in the total set of impacts.

This paper presents the rationale behind the development of a shoulder belt load cell suitable for application in racings cars. The design of the load cell and the operational parameters necessary for a research-quality measurement device for biomechanics research in racing car crashes and the performance of the device in sled tests are described.

The crash recorder is an important data gathering device in motorsports. Since the introduction of crash recording in Indy Cars in 1993, the data gathered has been critical in developing improvements in race car structures and driver protection systems. This report will examine which sanctioning bodies use recorders, what type of data is gathered, and how that data is used to improve driver's safety in racing.

This paper describes the results of a project to develop a MADYMO occupant model for predicting thoracolumbar (TL) spine injuries during frontal impacts in the Indianapolis-type racing car (ITRC) environment and to study the effect of seat back angle, shoulder belt mounting location, leg hump, and spinal curvature on the thoracolumbar region. The newly developed MADYMO Race Car Driver Model (RCDM) is based on the Hybrid III, 50th percentile male model, but it has a multi-segmented spine adapted from the MADYMO Human Facet Model (HFM) that allows it to predict occupant kinematics and intervertebral loads and moments along the entire spinal column. Numerous simulations were run using the crash pulses from seven real-world impact scenarios and a 70 G standardized crash pulse. Results were analyzed and compared to the real-world impacts and CART HANS® model simulations.

The purpose of this study is to provide an understanding of driver kinematics, injury mechanisms and spinal loads causing thoracolumbar spinal fractures in Indianapolis-type racing car drivers. Crash reports from 1996 to 2006, showed a total of forty spine fracture incidents with the thoracolumbar region being the most frequently injured (n=15). Seven of the thoracolumbar fracture cases occurred in the frontal direction and were a higher injury severity as compared to rear impact cases. The present study focuses on thoracolumbar spine fractures in Indianapolis-type racing car drivers during frontal impacts and was performed using driver medical records, crash reports, video, still photographic images, chassis accelerations from on-board data recorders and the analysis tool MADYMO to simulate crashes. A 50th percentile, male, Hybrid III dummy model was used to represent the driver.

Biomechanical analysis of Indy car crashes using on-board impact recorders (Melvin et al. 1998, Melvin et al. 2001) indicates that Indy car driver protection in high-energy crashes can be achieved in frontal, side, and rear crashes with severities in the range of 100 to 135 G peak deceleration and velocity changes in the range of 50 to 70 mph. These crashes were predominantly single-car impacts with the rigid concrete walls of oval tracks. This impressive level of protection was found to be due to the unique combination of a very supportive and tight-fitting cockpit-seating package, a six-point belt restraint system, and effective head padding with an extremely strong chassis that defines the seat and cockpit of a modern Indy car. In 2000 and 2001, a series of fatal crashes in stock car racing created great concern for improving the crash protection for drivers in those racecars.

The objective of this work was to evaluate a new tool for assessing brain injury. Many race car drivers have suffered concussion and other brain injuries and are in need of ways of evaluating better head protective systems and equipment. Current assessment guidelines such as HIC may not be adequate for assessing all scenarios. Finite element models of the brain have the potential to provide much better injury prediction for any scenario. At a previous Motorsports conference, results of a MADYMO model of a racing car and driver driven by 3-D accelerations recorded in actual crashes were presented. Model results from nine cases, some with concussion and some not, yielded head accelerations that were used to drive the Wayne State University Head Injury Model (WSUHIM). This model consists of over 310,000 elements and is capable of simulating direct and indirect impacts. It has been extensively validated using published cadaveric test data.

At the 2002 MSEC, we presented a paper on the sled test evaluation of racecar head/neck restraint performance (Melvin, et al. 2002). Some individuals objected to the 3 msec clip filtering procedures used to eliminate artifactual spikes in the neck tension data for the HANS® device. As a result, we are presenting the same test data with the spikes left in the neck force data to reassure those individuals that these spikes did not significantly affect the results and conclusions of our original paper. In addition we will add new insights into understanding head/neck restraint performance gained during two more years of testing such systems. This paper re-evaluates the performance of three commercially available head/neck restraint systems using a stock car seating configuration and a realistic stock car crash pulse. The tests were conducted at an impact angle of 30 degrees to the right, with a midsize male Hybrid III anthropomorphic test device (ATD) modified for racecar crash testing.

Recent developments in seat design for racecar drivers have proven to be very effective in minimizing injuries in side impacts. The features of the seats that present significant improvements over previous concepts are based on biomechanical principles that were learned from crash recorder based investigations of Indy car crashes. Insights gained from these studies led to an understanding of critical factors that provide effective support and protection of the driver in a high-severity side impact crash. Transferring these concepts from single seat chassis cars to stock car and sports car seats has led to significant improvements in driver side impact protection. The paper will describe these principles, present sled test performance data showing the benefits of proper seat design and will give examples of current commercially available seat designs for stock car and sports car racing.

Recent action by some racecar sanctioning bodies making head/neck restraint use mandatory for competitors has resulted in a number of methods attempting to provide head/neck restraint. This paper evaluates the performance of a number of commercially available head/neck restraint systems using a stock car seating configuration and a realistic stock car crash pulse. The tests were conducted at an impact angle of 30 degrees to the right, with a midsize male Hybrid III anthropomorphic test device (ATD) modified for racecar crash testing. A six-point latch and link racing harness restrained the ATD. The goal of the tests was to examine the performance of the head/neck restraint without the influence of the seat or steering wheel. Three head/neck restraint systems were tested using a sled pulse with a 35 mph (56 km/h) velocity change and 50G peak deceleration. Three tests with three samples of each system were performed to assess repeatability.

The close-fitting cockpit of the modern Indy car single seat race car has the potential to provide a high level of head and neck impact protection in rear and side impacts. Crash investigation has shown that a wide variety of materials have been used as the padding for these cockpits and, as a result, produced varying outcomes in crashes. Additionally, these pads have not always been positioned for optimal performance. The purpose of this study was to investigate the head impact performance of a variety of energy-absorbing padding materials under impact conditions typical of Indy car rear impacts and to identify superior materials and methods of improving their performance as race car head pads. An extensive series of tests with the helmeted Hybrid III test dummy head and neck on an impact mini-sled was conducted to explore head padding concepts.

This paper describes the results of an ongoing project in the GM Motorsports Safety Technology Research Program to investigate Indianapolis-type (Indy car) race car crashes using an on-board impact recorder as the primary data collection tool. The paper discusses the development of specifications for the impact-recording device, the selection of the specific recorder and its implementation on a routine basis in Indy car racing. The results from incidents that produced significant data (crashes with peak decelerations above 20 G) during the racing seasons from 1993 through the first half of 1998 are summarized. The focus on Indy car crashes has proven to provide an almost laboratory-like setting due to the similarity of the cars and to the relative simplicity of the crashes (predominantly planar crashes involving single car impacts against well-defined impact surfaces).

Two-dimensional film analysis was conducted to study the kinematics of the head and neck of 17 restrained human volunteers in 24 frontal impacts for acceleration levels from 6g to 15g. The trajectory of the head center of gravity relative to upper torso reference points and the rotation of head and neck relative to the lower torso during the forward motion phase were of particular interest. The purpose of the study was to analyze the head-neck kinematics in the mid-sagittal plane for a variety of human volunteer frontal sled tests from different laboratories using a common analysis method for all tests, and to define a common response corridor for the trajectory of the head center-of-gravity from those tests.

This paper describes the initial phases of an on-going project in the GM Motorsports Safety Technology Research Program to investigate Indy car crashes using an on-board impact recorder as the primary data collection tool. The development of a database consisting of crash investigation data patterned after national highway crash databases is discussed. The data gathered and coded includes track and incident scene information, vehicle damage, and driver injuries, as well as the vehicle decelerations measured by the impact recorder. The paper discusses the development of specifications for the impact device, the selection of the specific recorder and its implementation on a routine basis in Indy car racing. The results from incidents that produced significant data during the 1993, 1994 and 1995 racing seasons are summarized.

The purpose of this paper is to establish injury assessment reference values specific to the CRABI 6-Month infant dummy for use in evaluating the interaction of rear-facing infant restraints with a deploying passenger airbag. The available literature on the biomechanics of child injury and mechanical response and the results of impact tests with various child and infant dummies are reviewed and summarized. Estimations of the injury assessment reference values for use with the CRABI 6-Month dummy are made using scaling techniques based on the principles of dimensional analysis and dummy test data from infant restraint tests under conditions where injuries are not likely to occur. The information developed in this report will allow the assessment of injury potential in tests of the interaction of passenger airbags with rear-facing infant restraints. This issue is of particular importance to vehicles with only front seats, such as pickup trucks and sport vehicles.

This paper presents the results of a series of over 30 impact sled simulations of racing car frontal crashes conducted as part of the GM Motorsports Safety Technology Research Program. A Hyge™ impact sled fitted with a simulated racing car seat and restraint system was used to simulate realistic crash loading with a mid-size male Hybrid III dummy. The results of tests, in the form of measured loads, displacements, and accelerations, are presented and comparisons made with respect to the levels of these parameters seen in typical passenger car crash testing and to current injury threshold values.

This study is an extension of previous work on driver air bag deployment loads which used the mid-size male Hybrid Ill dummy. Both small female and mid-size male Hybrid Ill dummies were tested with a range of near-positions relative to the air bag module. These alignments ranged from the head centered on the module to the chest centered on the module and with various separations and lateral shifts from the module. For both sized dummies the severity of the loading from the air bag depended on alignment and separation of the dummy with respect to the air bag module. No single alignment provided high responses for all body regions, indicating that one test at a typical alignment cannot simultaneously determine the potential for injury risk for the head, neck, and torso. Based on comparisons with their respective injury assessment reference values, the risk of chest injury appeared similar for both sized dummies.

A two-dimensional finite element model of the head of a rhesus monkey was built to simulate the head acceleration experiments done by Gennarelli and his colleagues. The purposes of the study were to better understand the mechanisms of traumatic subdural hematoma and to estimate its threshold of occurrence. The brain was treated as an isotropic homogeneous elastic material with and without structural damping and the skull was treated as a rigid shell. To simulate Abel et al.'s (1) experiments, the head was subjected to an enforced forward rotation around the neck. The loading had an initial acceleration phase followed by deceleration. During both acceleration and deceleration phases, high shear stress (and thus strain) occurred at the vertex, where the parasagittal bridging veins are located. The deformation of the bridging vein depended on its orientation relative to the direction of impact.

Injury and disability associated with head (brain), neck (spinal cord) and facial injury account for 61.7% of the total societal Harm in the most recent estimate of motor-vehicle related crash injuries. This paper discusses the need for accurate information on translational and rotational acceleration of the head as the first step in critiquing the Head Injury Criterion (HIC) and other injury predictive methods, and developing a fuller understanding of brain and spinal cord injury mechanisms. A measurement system has been developed using linear accelerometers to accurately determine the 3D translational and rotational acceleration of the Hybrid III dummy head. Our concept has been to use the conventional triaxial accelerometer in the dummy's head to assess translational acceleration, and three rows of in-line linear accelerometers and a least squares analysis to compute statistical best-fits for the rotational acceleration about three orthogonal axes.

Two series of impacts to the head in the superior-inferior direction using 19 unembalmed cadavers are reported. The first series of five tests was aimed at generating kinematic and dynamic response to sub-injurious impacts for the purpose of defining the mechanical characteristics of the undamaged head-neck-spine system in the S-I direction. The second series of fourteen tests was intended to define injury tolerance levels for a selected subject configuration. A 10-kg impactor was used to deliver the impact to the crown at a nominal velocity of 8 m/s for the first series, and between 7 and 11 m/s for the second series. Measurements made in the first series include the impact velocity, force, and energy, the head three-dimensional kinematics, forces and moments at the occipital condyles, and accelerations of the T1, T6, and T12 vertebrae. Impact impedance curves were also generated.