Biofidelity Evaluation of AC-HUMs Pedestrian Model Based on Generic Sedan Buck Model

<div class="section abstract"><div class="htmlview paragraph">Objective: This study aims to evaluate the biofidelity of the Advanced Chinese Human Body Model (AC-HUMs) by utilizing a generic sedan buck model and post-mortem human surrogates (PMHS) test data.</div><div class="htmlview paragraph">Methods: The boundary conditions of the simulation were derived from the PMHS test with the buck vehicle. The methodology involved the pose adjustment of the upper and lower extremities of AC-HUMs, executed through a pre-simulation approach. Subsequently, a 200 milliseconds whole body pedestrian crash simulation was conducted using the buck vehicle and the AC-HUMs pedestrian model. The trajectories of AC-HUMs during the period from initial position to head impact were recorded, including the Head CG, T1, T8 and pelvis. Based on the knee joint, the corridors of trajectories from the PMHS test were scaled to match the Chinese 50<sup>th</sup> percentile male to evaluate the biofidelity of AC-HUMs's kinematic response.</div><div class="htmlview paragraph">Furthermore, the biomechanical responses were compared with the PMHS tests, including injuries of chest and lower extremities. This comparison comprehensively evaluated the injury prediction capability of the AC-HUMs pedestrian model under whole-body pedestrian collision scenarios.</div><div class="htmlview paragraph">Conclusion: The results indicate that the trajectories of the four markers on the AC-HUMs pedestrian model were all within the scaled trajectory corridors, confirming that the model exhibits good biofidelity. The results reconstructed similar ligament rupture scenarios (left LCL, right ACL, and MCL) as well as partial rib injuries. The findings also revealed potential biofidelity issues in the neck, ribs, knee joint, and tibia regions of the AC-HUMs model. Despite these challenges, the AC-HUMs pedestrian model demonstrates good biofidelity in motion trajectories and possesses the ability to replicate biomechanical responses. This indicates that the AC-HUMs model has significant potential for virtual vehicle safety assessments in China, positioning it as a promising tool for this purpose.</div></div>