Occupant Crash Response In Self-driving Car Seat Rotation Study

Since China entered the 21st century,automotive technology has been iteratively updated,making cars more intelligent and automated.The application of autonomous driving technology in the automotive field has effectively reduced the probability of automobile collisions.Compared with traditional vehicles,configuration and orientation of Self-driving vehicle seat are more diversified is more diversified than traditional vehicles,but the current restraint system is designed for the seat facing forward.Whether traditional restraint systems can be applied to self-driving vehicles to protect effectively occupants is still unknown.Flexible seat orientation will pose a great challenge for occupant protection in autonomous vehicle crashes.Therefore,in this paper,a rotating crash seat model based on an autonomous vehicle is developed to study the occupant kinematics and biomechanics after a crash.Firstly,the car rotating seat model was built based on the finite element software.Secondly,the established rotating seat model and the finite element human model were assembled to build a rotating crash model,and the validity of the built model was verified by comparing the data and kinematic response of the simulation test with that of the bench test.Then,the seat was rotated ±30°,±60° and ±90° within 200ms to study the biological response of the occupants.Next,the seat and occupant were rotated to the backward impact direction within 200ms and then crash acceleration was applied to investigate the effect of this strategy on occupant protection.Finally,the seat backrest angle and the distance between the headrest and the occupant’s head were varied to study the occupant head injury under the rotational crash strategy.The results of the study showed that:the seat was rotated ±30°,±60° and ±90° within 200ms,and no additional injury was caused to the occupants at the end of the rotation test;the strategy of rotating the seat and occupants to the backward impact direction within 200ms before applying the crash acceleration can reduce effectively the occupant injury,in addition,the risk of occupant injury increases when the seat rotation speed increases;the occupant head injury under the rotation crash strategy can be reduced effectively by adjusting the seat backrest angle and the distance between the occupant’s head and the headrest.This paper further investigates the biomechanical response and injury study of occupants based on the rotate first and crash later strategy in self-driving vehicles to provide some reference for future self-driving vehicle occupant protection.