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The aim of this study was to assess the feasibility of using a high speed x-ray system (capable of 1000 frames/sec) to evaluate the bony kinematics of post mortem human surrogate (PMHS) cervical spines at real world speeds during frontal impact. Whole body frontal impact sled tests were performed on two fresh PMHS specimens. Screws were inserted into the tips of the spinal processes to optimize contrast on the high speed cine x-ray. Head, T1 and sternum accelerations, as well as shoulder, and lap belt forces were recorded. Vertebral motion was captured using a modified mobile c arm x-ray system, and an image intensifier linked to a high speed camera (Kodak motion corder analyzer, model SR 1000C, Kodak, San Diego, CA, USA) The variable parameters for the tests were camera frame rate and sled velocity. Tests were performed with delta-V’s (Δv) of approximately 15 kph (8G) and 21 kph (10G). Cine x-rays of the tests were recorded at 250, 500 and 1000 frames/sec.

Sled testing is one of the most important test methods for the evaluation of vehicles interior with respect to crash safety. This method allows one to simulate real crash conditions without destroying the vehicle structure. In addition to conventional sleds which are accelerated smoothly using a bungee cord or other device and then impact a deformation element, catapult sled types act in a reverse mode. The sled is thus accelerated for approximately 100 ms to the impact speed and then smoothly decelerated. To ensure good correlation with the full scale crash test an accurate modelling of the vehicles crash pulse must be guaranteed Catapult type sleds guarantee, that the sled will not move before the pulse starts. Therefore well defined initial conditions especially regarding dummy positioning can be guaranteed. While conventional catapult type sleds mainly work on hydraulic or pneumatic modulation of the pulse.

During recent years the accident simulation program PCCRASH was developed, which allows to simulate the vehicles movement before, during and after the impact. As shown in several publications, the software allows to calculate the 3D movement of all involved vehicles. Within SAE 1999-01-0444 a new coupling interface of PC-CRASH and the software MADYMO, developed by TNO in the Netherlands was published. During last year's publication only few validation cases, mainly related to rear end impacts could be demonstrated. In the mean while several well documented tests have been performed to validate the performance of this model also in frontal and lateral collisions as well as rollovers. A special series of sled tests has been performed to study the movement of the passenger during and after the collision for various impact angles. These tests were performed on an active sled at various test speeds.

In 3D simulation of vehicle accidents the vehicles are typically treated as one rigid body. This simplification can be used for vehicle to vehicle collisions as well as in impacts with solid objects. To get a realistic movement of the pedestrian in the impact simulation, the pedestrian has to be modeled as a system of rigid bodies interconnected by joints. This paper describes in detail the extension of the discrete kinetic time forward simulation program PC-Crash to deal with multi-body-systems. As one application of this model pedestrians have been modeled. During the generation of this pedestrian model special interest has been focused on a realistic movement of the pedestrian and a short calculation time. The pedestrian model shows to be a good tool to analyze the movement of the pedestrian regarding its post impact kinematics and contact locations on the vehicles and the ground.