Design of an automotive subframe by topological optimization

Abstract

The subframe is one of the heaviest parts in an automobile and, at the same time, it is one of the most rigid. Mass reduction in automobiles has become a design requirement to improve energy efficiency, which is why lightweight structures are required. In this work the front subframe of a generic automobile is designed applying topological structural optimization. The objective is to determine the optimal distribution of the subframe mass, which maximizes stiffness and reduces weight. General bump, sudden turning, acceleration, and abrupt braking load cases are considered. After adaptation for manufacture, the generated subframe could be made of steel or aluminum, weighing less than 20 kg and 7 kg, respectively. It means significant differences in comparison with conventional subframes, which weigh between 10 kg and 25 kg.