Mass Optimized Hood Design for Conflicting Performances

Passenger vehicles have stringent safety regulations for pedestrian protection to meet child and adult head impact requirements to minimize injuries. These pedestrian safety requirements often conflict with stiffness and durability performance criteria, which pose a challenge for most automotive OEMs. There is a growing need for performance balancing to meet both these loadcases. This paper uses Multi-Disciplinary Optimization (MDO) approach involving shape variables to achieve optimized performance for stiffness, durability and pedestrian safety.

The current study describes an approach that helps reduce time and efforts needed to resolve performance issues between both stiffness/durability and Pedestrian safety requirements. This approach not only helps find a feasible cross-functional solution but also provides an opportunity to reduce the overall development cycle time and mass whenever possible. It also demonstrates the importance of shapes and dimensions of slots on the inner panel as variables. The slots on inner panel and palm reinforcement are observed to be most sensitive, whereas thicknesses of inner panel, palm and latch reinforcement are the most sensitive size variables. It also involves using a reduced content model, which would reduce the computational time significantly without compromising on physics of the problem and accuracy of results.