Research on the Boundary of Pedestrian Leg Impactor Test in Low-Speed Passive and Active Conditions

With the widespread application of the Automatic Emergency Braking System (AEB) in vehicles, its impact on pedestrian safety has received increasing attention. However, after the intervention of AEB, the kinematic characteristics of pedestrian leg collisions and their corresponding biological injury responses also change. At the same time, in order to accurately evaluate the pedestrian protection performance of vehicles, the current assessment regulations generally use advanced pedestrian protection leg impactors (aPLI) and rigid leg impactors (TRL) to simulate the movement and injury conditions of pedestrian legs. Based on this, in order to explore the collision boundary conditions and changes in injury between vehicles and APLI and TRL leg impactors under the action of AEB, this paper first analyzes the current passive and active assessment conditions. Secondly, the simulation software LS-DYNA is used to build a finite element model of APLI and TRL impactor-vehicle collisions to analyze the changes in collision boundary conditions between leg impactors and vehicles. Finally, based on the simulation model, the changes in injury of leg impactors with and without AEB are further analyzed. The research results show that after the intervention of AEB, the impact positions of aPLI and TRL on the front of the vehicle will change, and the change of sedan is more significant than that of SUV. At the same time, under the action of AEB, the damage of aPLI and TRL will change significantly, and the damage change of SUV is more prominent than that of sedan. At the same time, the front edge position of the vehicle is more sensitive. This study provides important theoretical support for the subsequent integrated safety assessment of pedestrian protection, provides design references for future pedestrian protection regulation assessments, and has important guiding significance for the optimization of vehicle front-end structures.