Study On The Effect Of Frontal Offset Collision On Lower Limb Injury Of Driver

With the increasing of the car ownership rate,the situation of road traffic accidents has become increasingly severe.Frontal collisions,one of the main forms of vehicleto-vehicle collisions,occurred frequently,and offset collisions accounted for about half of frontal collisions.With a high incidence of crushing the cockpit,offset collisions brought a huge amount of intrusion to the occupants’ lower limbs and caused serious damage.Lower limb injury was the main factor of permanent physical disability of occupants,which had a huge i MPact on individuals,families,and society.The research on lower limb injury in full-width collisions has been developed well,but the research on lower limb injury in offset collisions was not comprehensive.Considering that driver was more susceptible to lower limb injury than other occupants,the research on driver’s lower limb injury is of great significance.The research purpose of this paper is to explore the i MPact of frontal offset collision on driver’s lower limb injury.A driver’s lower limb model with activated muscle force was developed according to constitutive model of the muscle.The quasistatic and dynamic three-point bending simulation of each part of the model was carried out.What’s more,a simplified model including hybrid dummy model,occupant restraint system and cabin was developed and verified.Acceleration and intrusion curves at different collision overlap rates(25%,40% and 100%)and collision velocity(40km/h,50km/h,and 64km/h)of the validated vehicle models were extracted as input to the simplified model.Three factors,collision overlap rate,collision speed and muscle activation state,were set up to establish 8 groups of simulation sequences.The results show that offset collision increase the risk of driver’s lower limb injury.The injury of the left lower limb in the frontal 40% overlap collision was higher than that in the frontal 25% overlap collision.This is due to the loss of the left front tire during the frontal 25% overlap collision,which results in lower injury levels in the left lower limb than in the frontal 40% overlap collision.Because of the intrusion quantity of the left and right pedals,the injury level of the left lower limb in the offset collision was serious.The upper tibia is more vulnerable to injury than the lower tibia due to the excessive bending moment of the upper tibia.The risk of lower limb bone injury increases with the increase of i MPact velocity.When the quantity of intrusion reaches100 mm,the risk of femur injury will increase sharply with the increase of the amount of intrusion.Muscle activation has significant influence on axial force of femur but little influence on tibia.Muscle activation has the greatest influence on femur,which significantly increases the risk of femur injury.With the increase of i MPact speed,the risk of femur injury increases slowly with muscle activation.