Blog #3 -- Design Details -- May 16th, 2023

     This blog will be a more in-depth account of the design process and details. Picking up from the last blog, we found the initial models that we would be testing against each other and had a pretty good sense that we would be going with the model that was tested in a rocketry lab over the model that was found online with no caption. The only problem with this design was that there were no premade designs for the intake and the diffuser of this model. Because of this, we had to design our own inlet flange and diffuser. Additionally, the model that was used in the lab was a parametric model, which meant we had to navigate additional software (OpenSCAD) if we wanted to customize it in any way. Because these designs were premade, it was also much more difficult to manipulate them in Fusion360 because they came as simple meshes. 

   

    Despite all these potential complications, the inlet flange just required us to draw an arc around the profile of the compressor and then revolve it, and the diffuser was pretty easy to make based on other diffuser designs that were available for different compressors. The next step was to get these 3D models to become schematic drawings that we could use to reference and troubleshoot during our prototyping process. 

    Even after resolving all of the initial design issues, there was still the issue of connections and printability. We needed to be able to connect all three plastic parts (the inlet, diffuser, and tube) together solidly without any air gaps which would cause a loss in pressure or efficiency. We ended up using a variety of methods to connect them which you can see in the designs, but it ultimately affected the printability of the part. Since our initial plan was to simply weld everything together, a skill that we had been developing for a couple of months, this problem was initially quite frustrating, as we began resorting to what seemed like rudimentary ways of joining parts. All in all, the beginning of the design process was met with several iterations of the initially simple design to accommodate various details that were initially overlooked. The silver lining of not manufacturing these parts out of metal like we initially planned is that we can now insert the ball bearing directly into a printed part instead of worrying about how to attach it securely. Even this comes with its own complexity, but we'll wait until tomorrow to see how the print turns out.