Enhancing Crashworthiness of AAM Using Hybrid Energy Absorbing Structure Based on Additively Manufactured Ti-6Al-4V Lattice Structures

초록

To satisfy crashworthiness requirements during emergency landings, AAM (Advanced Air Mobility) platforms require a structurally efficient subfloor that can absorb significant impact energy without compromising overall integrity. This study proposes a hybrid subfloor system that integrates a lightweight aluminum framework with Ti-6Al-4V lattice structures fabricated via EBM (Electron Beam Melting) additive manufacturing. The configuration is designed to enhance energy absorption performance through plastic deformation mechanisms in response to vertical impact scenarios. The subfloor structure comprises key components, including the keel beam, bulkheads, lateral skin panels, and energy-absorbing modules. The keel beam functions as the primary longitudinal load path and distributes crash-induced forces across the airframe. Bulkheads serve to distribute mechanical loads and contribute to torsional stiffness, while lateral skin panels preserve aerodynamic continuity and provide limited secondary resistance during impact events. Ti-6Al-4V lattice absorbers are strategically embedded beneath high-load zones to facilitate progressive and controlled plastic deformation, thereby reducing accelerative forces transmitted to the cabin floor and enhancing occupant safety. To validate the performance of the Ti-6Al-4V lattice energy absorbers, a representative unit structure is designed and modeled using CATIA and subsequently analyzed under quasi-static compressive conditions using Abaqus/Explicit.