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To date, anthropomorphic test devices (ATDs) have not been designed with consideration for human motion in far-side impacts. Previous tests with a cadaver and a BioSID dummy at the Medical College of Wisconsin confirmed that the dummy does not suitably model the human motion. To further evaluate different ATDs in far-side crashes, MAthematical DYnamic MOdeling (MADYMO) was employed. The modeling showed that the motion of a Hybrid III, BioSID, EuroSid1, EuroSID2, or SID2s did not accurately reflect the motion of a human cadaver under the same impact configurations as the cadaver test. The MADYMO human facet model was found to closely reproduce the kinematics of the cadaver test. The effect of varying console designs on occupant kinematics is presented in this paper. The human facet model appears to be a good interim tool for the evaluation of countermeasures in far-side crashes.

In December 2003, fifteen participating Automobile Manufacturers announced the adoption of voluntary standards for geometric compatibility in frontal crashes. In an October 2003 report, Insurance Institute of Highway Safety (IIHS) estimated that an 8 to 28 percent fatality reduction might be achieved with better geometric and stiffness compatibility (O’Neill, 2003). This benefit was based on comparing the fatality risks of car occupants in car-to-car collisions and in car-to-SUV collisions. Reduced occupant compartment intrusion was cited as the principal advantage gained by compatibility improvements. However, the study did not actually examine the role that intrusion played in causing the fatalities. This study examines the magnitude of serious injuries in frontal crashes that could be addressed by reducing occupant compartment intrusion. Each frontal vehicle-to-vehicle case in William Lehman Injury Research Center (WLIRC) data was examined to determine the cause of each injury.

In the effort to understand and solve the frontal crash compatibility problem, one needs to use values of frontal stiffness. Various definitions of stiffness have been used in other studies based on measurements from NHTSA's 35mph frontal NCAP test. Those definitions varied from assuming a linear stiffness based on static crush to more refined ones that vary with time dependent crush. A major consideration in selecting a method is the amount of vehicle damage that occurs in an incompatible crash. To partially address this issue, a method was introduced based on the energy absorbed in a front to front crash at 25mph approach speed. Four alternative definitions of stiffness were studied.

The U.S. Department of Transportation-sponsored Crash Injury Research and Engineering Network (CIREN) program offers a reasonable look at the efficacy of second-generation air bags. This paper examines the data from the William Lehman Injury Research Center (WLIRC). The WLIRC data is a near census of crashes in the Miami-Dade region with occupants that appear to be severely injured. The percentage of deaths among trauma patients in the WLIRC data as a function of delta-V for first-generation air bags was higher than expected at lower delta-V's. There were nine driver fatalities at delta-V's of less than 20 mph (four involving short stature occupants, four with elderly occupants, and one due to significant intrusion and/or vehicle incompatibility). The data supported NHTSA's conclusion that first-generation air bags were too aggressive for occupants in close proximity to the deploying air bag and too aggressive for older persons.

The number of passenger vehicles with combined 3-point belt/driver air bag restraint systems is steadily increasing. To investigate the effectiveness of this restraint combination, 48 kph frontal collisions were performed with human cadavers. Each cadaver's thorax was instrumented with a 12-accelerometer array and two chest bands. The results show, that by using a combined standard 3-point belt (6% elongation)/driver air bag, the thoracic injury pattern remained located under the shoulder belt. The same observation was found when belts with 16% elongation were used in combination with the driver air bag. Chest contours derived from the chest bands showed high local compression and deformation of the chest along the shoulder belt path, and suggest the mechanism for the thoracic injuries.

The study reports on the results of frontal collisions with 16 cadavers and two Hybrid III dummies with impact velocities of 48 km/h to 55 km/h and a mean sled deceleration of 17 g; mounted to the sled was the front part of a passenger compartment. The cadavers were restrained in the driver position with either 3-point belts (6% and 16 % elongation) and/or air bag with knee bolster and one case was unrestrained. In most cases, both a 12-accelerometer thoracic array and 2 chest bands were employed. In some cases the acceleration at Th6 was measured. The cadavers were autopsied and the injury severity was rated according to the AIS 90. Maximum resultant Th1, Th6, and Th12 accelerations or sternum accelerations in x-direction ranged from 35g to 78g when using 3-point belts and produced injuries ranging from a few rib fractures to unstable chest wall (flail chest).