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Biomechanical data on the response of the face to localized and distributed loads are analyzed to provide performance goals for a biomechanically realistic face. Previously proposed facial injury assessment techniques and dummy modifications are reviewed with emphasis on their biomechanical realism. A modification to the Hybrid III dummy, called the GM Hybrid III Deformable Face, is described. The modification produces biomechanically realistic frontal impact response for both localized and distributed facial loads and provides for contact force determination using conventional Hybrid III instrumentation. The modification retains the anthropometric and inertial properties and the forehead impact response of the standard Hybrid III head.

For prescribed test conditions, a procedure is given for estimating the response characteristics of an arbitrary chosen standard subject based on the measured responses of subjects with different physical characteristics. Simple model analysis is used to develop the relationships between the subjects' responses and their physical characteristics. This analysis assures dimensional correctness among the critical parameters. The technique is applied to force-time data obtained by the Association Peugeot-Renault for lateral thoracic impacts of cadaver specimens. An averaged, normalized response curve is given for each of two impact conditions. A response corridor is prescribed for each average curve. These corridors can be used to assess the efficacy of various proposed thoracic side impact test devices exposed to similar impact conditions.

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.

Objective: This study investigated the incidence of abdominal injuries in frontal crashes by occupant age and seating position. It determined the risk for abdominal injury (AIS 2+) by organ and injury source. Methods: 1997-2015 NASS-CDS was analyzed to estimate the occurrence of abdominal injuries in non-ejected, belted occupants involved in frontal crashes. Vehicles were included with 1997+ model year (MY). The annual incidence and rate for different types of abdominal injury were estimated with standard errors. The sources for abdominal injury were determined. Results: 77.8% of occupants were drivers, 16.7% were right-front passengers and 5.4% were rear passengers. Rear passengers accounted for 77.1% of 8-11 year old (yo) and 17.2% of 12-17 yo group. The risk for moderate abdominal injury (MAIS 2 + abdo) was 0.30% ± 0.053% in drivers, 0.32% ± 0.086% in right-front passengers and 0.38% ± 0.063% in rear occupants.

It is well known that the ability of the human body to withstand trauma is a function of its inherent strength, i.e., the strength of the bones and soft tissues. Yet, the properties of the bones and tissues change as a function of the individual's age. In this paper age effects on thoracic injury tolerances are studied by analyzing the mechanical properties of human bones and soft tissues and by examining experimental results found in the literature of thoracic impact tests to human cadavers. This work suggests that the adult age range can be divided into three age groups. Using piece-wise linear regression analyses, it has been determined that the reduction in injury tolerance from the “young” age group to the “elderly” group is approximately 20% under blunt frontal impact loading conditions and is as much as 70% under belt loading conditions.

Injury Risk Curves are developed from cadaver data for sternal deflections produced by anterior, distributed chest loads for a 25, 45, 55, 65 and 75 year-old Small Female, Mid-Size Male and Large Male based on the variations of bone strengths with age. These curves show that the risk of AIS ≥ 3 thoracic injury increases with the age of the person. This observation is consistent with NASS data of frontal accidents which shows that older unbelted drivers have a higher risk of AIS ≥ 3 chest injury than younger drivers.

The purpose of this literature review was to determine areas of automotive injury information that may add to knowledge of injury type, frequency, severity, and cause. This paper is a review of the literature concentrating on the period between 1965 and present. Literature on car, van, or 1ight truck occupants has been reviewed for injury frequencies, types, and locations. Current experimental biomechanical articles are also included. A search was made for descriptions of injury frequency, restraint effectiveness, and the causes of specific injuries. Medical and engineering journals, texts, and books were reviewed. For convenience, this report is divided into sections by body region with an overview introduction on the anatomy of the specific region.

This paper details the development of an abdominal injury assessment device for loading due to belt restraint submarining in the Hybrid III family of dummies. The design concept and criteria, response criteria, choice of injury criterion, and validation are explained. Conclusions of this work are: 1) Abdominal injury assessment for belt loading due to submarining is now possible in the Hybrid III family of dummies. 2) The abdomen developed has biofidelity in its force deflection characteristics for belt loading, is capable of detecting the occurrence of submarining, and can be used to determine the probability of abdominal injury when submarining occurs. 3) Installation of the abdomen in the Hybrid III dummy does not change the dummy kinematics when submarining does not occur. 4) When submarining does occur, the dummy kinematics are very similar to baseline Hybrid III kinematics, except for torso angle.

The purpose of this study was to investigate approaches evaluating the performance of safety systems in crash tests and by analytical simulations. The study was motivated by the need to consider the adequacy of injury criteria and tolerance levels in FMVSS 208 measuring safety performance of restraint systems and supplements. The study also focused on additional biomechanical criteria and performance measures which may augment FMVSS 208 criteria and alternative ways to evaluate dummy responses rather than by comparison to a tolerance level. Additional analysis was conducted of dummy responses from barrier crash and sled tests to gain further information on the performance of restraint systems. The analysis resulted in a new computer program which determined several motion and velocity criteria from measurements made in crash tests.

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.

Blunt impacts to the back of the torso can occur in vehicle crashes due to interaction with unrestrained occupants, or cargo in frontal crashes, or intrusion in rear crashes, for example. Six pendulum tests were conducted on the back of an instrumented 50th percentile male Hybrid III ATD (Anthropomorphic Test Device) to determine kinematic and biomechanical responses. The impact locations were centered with the top of a 15-cm diameter impactor at the T1 or at T6 level of the thoracic spine. The impact speed varied from 16 to 24 km/h. Two 24 km/h tests were conducted at the T1 level and showed repeatability of setup and ATD responses. The 16 and 24 km/h tests at T1 and T6 were compared. Results indicated greater head rotation, neck extension moments and neck shear forces at T1 level impacts. For example, lower neck extension was 2.6 times and 3.8 times greater at T1 versus T6 impacts at 16 and 24 km/h, respectively.

Purpose: This study investigates NASS-CDS data on basilar skull fractures by crash type and injury source for various crash scenarios to understand the injury risks, injury mechanisms and contact sources. Methods: 1993-2008 NASS-CDS data was used to study basilar skull fractures in adult front occupants by crash type and injury source. Injury risks were determined using weighted data for occupants with known injury status in 1994+ model year vehicles. In-depth analysis was made of far-side occupants in side impacts and rear crashes using the NASS electronic cases. Results: Basilar skull fractures occur in 0.507 ± 0.059% of rollovers and 0.255 ± 0.025% of side impacts. The lowest risk is in rear impacts at 0.015 ± 0.007%. The most common contact source is the roof, side rails and header (39.0%) in rollovers, the B-pillar (25.8%) in side impacts and head restraint (55.3%) in rear crashes.

Side impact pendulum tests were conducted on Eurosid I and Biosid to assess the biofidelity of the thorax, abdomen and pelvis, and determine injury tolerance levels. Each body region was impacted at 4.5, 6.7, and 9.4 m/s using test conditions which duplicate cadaver impacts with a 15 cm flat-circular 23.4 kg rigid mass. The cadaver database establishes human response and injury risk assessment in side impact. Both dummies showed better biofidelity when compared to the lowest-speed cadaver response corridor. At higher speeds, peak force was substantially higher. The average peak contact force was 1.56 times greater in Biosid and 2.19 times greater in Eurosid 1 than the average cadaver response. The Eurosid I abdomen had the most dissimilar response and lacks biofidelity. Overall, Biosid has better biofidelity than Eurosid I with an average 21% lower peak load and a closer match to the duration of cadaver impact responses for the three body regions.

An analysis was done of published forehead head impact data from cadaver specimens. Only data that were sufficiently documented to allow duplication of the impact environment were used in the analysis. A Hybrid III head, a Part 572 head, a Repeatable Pete head and two WSU heads were subjected to the same impact environments as the cadavers. A comparison of peak resultant head accelerations indicated that the Hybrid III response was the most representative of the cadaver data. The Part 572 head produced accelerations which were greater than the responses of the cadavers. These results support the claim that the Hybrid III head's response is humanlike for forehead impacts.

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).

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.

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.

In 1983, General Motors Corporation (GM) petitioned the National Highway Traffic Safety Administration (NHTSA) to allow the use of the biofidelic Hybrid III midsize adult male dummy as an alternate test device for FMVSS 208 compliance testing of frontal impact, passive restraint systems. To support their petition, GM made public to the international automotive community the limit values that they imposed on the Hybrid III measurements, which were called Injury Assessment Reference Values (IARVs). During the past 20 years, these IARVs have been updated based on relevant biomechanical studies that have been published and scaled to provide IARVs for the Hybrid III and CRABI families of frontal impact dummies. Limit values have also been developed for the biofidelic side impact dummies, BioSID, EuroSID2 and SID-IIs.

In 1983, General Motors Corporation (GM) petitioned the National Highway Traffic Safety Administration (NHTSA) to allow the use of the biofidelic Hybrid III midsize adult male dummy as an alternate test device for FMVSS 208 compliance testing of frontal impact, passive restraint systems. To support their petition, GM made public to the international automotive community the limit values that they imposed on the Hybrid III measurements, which were called Injury Assessment Reference Values (IARVs). During the past 20 years, these IARVs have been updated based on relevant biomechanical studies that have been published and scaled to provide IARVs for the Hybrid III and CRABI families of frontal impact dummies. Limit values have also been developed for the biofidelic side impact dummies, BioSID, ES-2 and SID-IIs.