On Designing RWX's Frame
Written by: Pranav Sridhar
The frame of a race car is without a doubt a topic of much needed discussion and debate. The Chassis-frame Engineers are always posed with the challenge of making a strong and stiff car.
While designing the frame, the team has to comply with the FSAE rules that make it structurally sound and safe enough for the competition. The frame is designed around the suspension but at the same time other subsystems and their respective designs have to be accommodated.
This year’s car, RWX, had very clear goals when it came to weight reduction. Since the frame makes up approximately 35% of the total weight of the car, the frame team had quite a challenge ahead of them. However, reduction in weight without a definitive design-for-stiffness direction might lead to a frame that is light but flexible. Any compliance (flexing) at the frame drastically reduces suspension performance and tire contact patches which translate into slower speeds at corners or an uncontrollable car.
The Frame Engineers decided to go with a calculated approach to designing the frame. We first estimated how stiff the frame would need to be using suspension design data. On arriving at an optimum stiffness range, the team decided to use FEA (Finite element method) software tools to iteratively make improvements. The whole exercise was a trade off between torsional stiffness, strength, and weight. After countless hours of effort, we finalized a design and began manufacturing. With the frame completed, RWX’s journey to MIS is on schedule - faster, stiffer, and lighter. As we continue with our design and manufacturing process, Warrior Racing is excited to compete at the Michigan International Speedway in May.