Analysis of the side impact process of door interior panel assembly and structure optimization

With the increasing incidence of injuries from automobile side-impact collisions, it is critical to investigate occupant biomechanical responses, particularly in the shoulder, abdominal, and pelvis regions. This study simulates side intrusion impacts on the rear door interior panel assembly using HyperMesh for pre-processing and LS-DYNA as the dynamic solver. The analysis examines the effects of different collision regions on occupant injury metrics and transient impact forces. Results show that maximum impact forces in the abdominal region exceed 2 kN, whereas forces in the pelvis region remain below 2 kN at a deformation of 15 mm. The failure of plastic clips securing the interior panels can lead to panel detachment, which directly strikes the occupant and increases the risk of injury. A structural optimization of the panel fasteners was proposed, enhancing both connection strength and energy absorption. The improved design prevents detachment during side impacts and ensures that all measured forces remain within safety thresholds. These findings provide a foundation for improving the structural integrity and crashworthiness of automotive door interior panels, thereby enhancing occupant safety in side collisions.