THE ANALYSIS OF OCCUPANT MOTION IN FRONTAL BARRIER IMPACT OF A CHASSIS FRAME VEHICLE1

Human body motion during a road accident usually results from the effect of forces of inertia. The analysis of that motion, particularly displacements towards the vehicle interior have significant practical aspect as it facilitates conclusions concerning the mechanisms of danger and injury formation. At the same time, the analysis provides direct indications regarding the improvement of passive safety equipment. The paper presents the time-space diagrams of motion of dummy’s head, neck, torso and hips – the driver of a frame chassis vehicle, identified on the basis of results of the measurements registered in frontal barrier impact and the frame-by-frame analysis of videos recorded during the course of experiment. Courses of these diagrams were associated with acceleration measurement results and forces affecting the parts of the dummy. The experiment showed the complex nature of the influence on the dummy caused by the forces of inertia after a collision of the vehicle with an barrier, vehicle body motion against the frame, reactions in the safety belts, friction on a seat and contact reaction of the vehicle interior equipment. At the same time, it presented the possibilities of indicating the courses of speed variations and dummy displacement as well as significant limitations of calculation possibilities that result from a fact that the process of the impact on the vehicle interior elements is hard to describe