Dissolvable Support Rear Wing Holder

An important aspect of a high performance FSAE car is managing the total weight. One area for improvement in the 2019 Season was the rear wing holder weight. The current design is a simple 2D sandwich lamination with unidirectional carbon following the estimated load paths. This presented a problem with YAW instability during testing.

A new design approach is needed in order to incorporate vertical load requirements in conjunction with YAW stability.

My idea is to 3D print an internal structure out of a dissolvable filiment, wrap the geometry in Prepreg, and when cured, simply dissolve the support leaving a hollow carbon structure.

To accurately determine potential load paths, I used Altair Inspire to optimize the topology for our requirements. This starts with defining:

A design space for optimization

Attachment points

Load forces

After performing many simulations with different loads and settings. I settled on this optimization that seemed to structure the loads in a sensible way.

Altair Inspire has a great feature (Polynurbs) for creating organic shapes. This structure will be the basis for the upcoming work to be done in Solidworks.

After this design is finished, i will upload the STEP file and add a path for the Prepreg to follow. The wrapping procedure will be the most difficult of all as shown in the next step.

The wrapping procedure will be an intricate process. This is because any overlaps between Prepreg strips will double the laminate thickness causing local high and low spots in the structure.

This will be a critical step in realizing this project so I am planing on printing test samples to determine the layup before a soluble lamination is made

Here we can see the channels that need to be cut into the Polynurb 3D print. The YAW support beams will create nodes with higher laminate overlaps. Therefore the channels can compensate for this thickness increase and distribute internal stresses more efficiently.