The variation of throwing distance and Head Injury Criterion with velocity, point of impact and angle of approach has been studied for bicycle impact with three different categories of vehicles- small cars, sports utility vehicles and buses. Crashes between a bicycle and the vehicles were simulated using multi body models developed in MADYMOTM with parametric variations in speed, angle of approach and point of impact. The variation in the angle of approach or point of contact causes significant changes. From the simulations, the large spread in the data reported by reconstruction is predicted to originate from variation in the impact configuration. The changes in the trends can be associated with visible kinematics in the simulations (head impacting car, no impact of rider with car etc.). The kinematics of impact is significantly different for the bus and this leads to changes in the nature of correlations. The HIC values were found to be higher in the case of bus as compared to the SUV and the small car. The paper reinforces the hypothesis that for bicycle accident reconstruction should take into account variations in the impact configuration in addition to the throw distance recorded. The paper also gives data which could form a basis of such reconstructions.
Keywords:
Bicycle; MADYMO; Crash simulation; throwing distance; impact speed