ALUMINUM SUBFRAME DESIGN FOR CRASH ENERGY MANAGEMENT. IN: CAE METHODS FOR VEHICLE CRASHWORTHINESS AND OCCUPANT SAFETY, AND SAFETY-CRITICAL SYSTEMS

This paper first reviews various subframe concepts. Their design intents and vehicle performance are discussed. A development process of an aluminum subframe is then presented detailing the subframe design as an energy absorbing component for frontal impacts. The architecture of the subframe is developed based on overall functionality requirements and package constraints. The geometry of the subframe is designed to accommodate engine mounts and suspension support locations. The subframe member's shape, orientation, and location are then refined to incorporate the subframe-to-body connection requirements. A finite element model is built to simulate a 35-mph rigid barrier frontal impact for design investigations. Analytical results show that a subframe can be designed to meet its crash load carrying requirement and the desired deformation system. An optimization process shows the subframe load capacity can meet a range of energy management targets by modifying key elements. A deformable/detachable mechanism has also been designed to reduce impact force transferred from subframe to body structure.