Efficiency of movable type of Child Safety Restraint Systems in the event of Head-on Collisions

The study provides a comparative analysis of the possibility of mitigating the effects of head-on collisions on approx. three-year old children transported in passenger cars in the safety seats moving relative to the car cabin in the event of a collision. Two seat fastening methods were considered: (a)—fixing the seat to the car cabin using a revolute joint with the axis perpendicular to the car symmetry plane, (b)—allowing the seat straight line motion along its symmetry plane. In both cases the seat was braked which resulted in specific dissipation of the impact energy. The adopted testing method was computer simulation using the MADYMO program. To assess the degree of injury risk reduction a synthetic injury risk index based on selected "biomechanical injury criteria" has been defined. The results prove considerable potential of reducing the risk of injury when using movable seats as compared to traditional solutions.