Topology Optimized Snowboard Binding

One of the bindings on my snowboard spontaneously broke on the slopes, and being in my first semester of college, I saw an opportunity to to design something that I could actually manufacture for the first time. I was and still am interested in learning more about topology optimization, and so I used this project as an excuse to use that design feature for the first time as well. 

 I used Fusion 360 as a CAD software for this project, and I tried their topology optimization feature for the first time during this project. On the left you can see my base shape that I created as a template for the binding to follow, and on the right you can see how fusion was able to subtract material according to the constraints I set, and the test load I applied. 

 While shape optimized simulation results can act as a good guide, I took the liberty of adding some thinner material back into the center of the part to help with strength and to eliminate sharp corners. I also added fillets where approprete as I was basing my model after the simulation results. I then used our Markforged Mark Two to print the part out of nylon. 

I chose to print the binding out of nylon because it is the most flexible material (while remaining strong) that I have access to. I was concerned about gauging the flexibility of the material thickness that I chose before I printed it, but the nylon behaved as expected and the part printed perfectly on the first iteration. 

 All there was left to do was reuse the hardware I saved from the broken binding, and test out the part.

I'm still really proud of this project because it was my first, but also because the binding works really well! I did test it out on the slopes and it's holding up great. If I were to do this again, I would definitely apply some of the math that I have since learned to better validate my design; but for what it is, I have no complaints. 

I am updating this project three years later to include some fun upgrades. One night on the slopes this year tragedy struck. My binding snapped near the buckle. Luckily I was able to salvage my snowboarding session, but the binding definitely needed an upgrade. 

The binding seemed like it snapped because it did not have enough stretch in the colder weather. I still wanted the binding to mostly not stretch because it needed to keep my foot secure, so I decided to compromise. I revised my design to be multi-material and included a TPU inner, while keeping my original nylon outer. I was really excited to try this out because since making my original design, the 3D print lab at my school got some new Ultimaker Factor 4 industrial printers. The amazing thing about these printers is that they can print multi-materials even if the materials are not compatible. On top if that, Cura recently introduced a feature called "Generate Interlocking Structures". This feature allowed me to "weave" the new TPU inner into my nylon base part, which was a game changer for durability.  

The images above show how the slicer weaves the materials together to create an impressively strong bond. 

The most difficult part was getting the rivets off of the old binding and attaching them to the new one. Rivets were the only solution for mounting the hardware because they were the only fastener shallow enough to allow the binding strap to slide through. 

Once I mounted the new bindings, the board was ready for the rest of the season. They are now even more secure and I feel more confident than ever on my board!