Research On Injury Analysis And Protection For The Rear Occupants In Reclined Postures Based On THUMS

With the rapid development of autonomous driving and intelligent cockpit technologies,passengers have increasingly high demands for the comfort of their car.Research has shown that when not performing driving tasks,passengers mostly prefer to recline their seatbacks and ride in a lying position in the car.Additionally,new types of car seats such as "zerogravity seats" and "queen co-pilot seats" have been introduced and put into production.However,current collision regulations only focus on protecting passengers in a standard seating position,there is an urgent need to conduct research on passenger protection in nonstandard seating positions under collision conditions.This article mainly conducts the following research through computer simulation: first,a restraint system model for a 100% frontal overlap rigid barrier collision is constructed,and model validation is completed by comparing with collision test data.Next,after comparing THUMS and Hybrid Ⅲ dummies,THUMS is selected for the subsequent research in this article.Then,the passenger injury under three different seating positions of 25°,35°,and 45°is compared,the integrated safety belt and anti-submarining method are used to solve the problem of increased head injury and submarining of THUMS in a reclined position.Finally,based on the Kriging method,a response surface proxy model is constructed with the goal of minimizing the WIC(Weighted Injury Criteria)for the three seating positions,and the MOGA-Ⅱ multi-objective genetic algorithm is used to perform multi-objective optimization on the restraint system parameters to balance passenger injury in the three seating positions.The research results show that THUMS is more detailed in terms of kinematics and injury response compared to the Hybrid Ⅲ dummy,and is more suitable for simulating passengers at different angles.As the reclining angle increases,the head injury of THUMS increases,and the trend of pelvis moving forward and pressing down on the seat cushion increases,and submarining occurs in the 45° seating position.The integrated safety belt can reduce the head injury of THUMS in the three seating positions,and increasing the stiffness of the anti-submarining seat cushion is the most helpful for solving the submarining problem.Moving the anchor point forward and reducing the buckle height can also help to suppress submarining.The multi-objective optimization results of the constraint system parameters show that the WIC can be reduced by 36.26% in the 25° seating position,6.82% in the 35°seating position,and 12.82% in the 45° seating position.This study can provide reference for passenger protection in non-standard seating positions.