Abstract: A simulation model was established to analyze the kinematic characteristic of the elasticplastic debris in the vehicle collision under following 4 different initial conditions: 1）the same falling height and the different initial velocities; 2) the same falling velocity and the different falling heights; 3) the same falling height and initial velocity and the different thrown angles; 4) the same initial velocity and thrown angle and the different debris shapes. The relationships between the debris thrown distance and the initial velocity, the thrown angle, the falling height, as well as the debris shape were simulated by the established model. The results show that under condition of the same air drag, road friction as well as debris mass and volume, the shape and the initial angle of the falling debris have the large effect on the thrown distance, and the area of debris windward side is the key factor to determine the moving time duration and the rolling and skidding behaviors of the debris on the road. When the debris initial angle is from -65°to 45°, its trajectory accords with the theory of the outer ballistics, however, when the initial angle is from -90°to -65°or from 45°to 90°, the debris will rebound, diverging from the outer ballistics theory.

Key words: vehicle engineering, vehicle collision, elasticplastic debris, kinematic characteristic, simulation