Bottle Opener Finale: 2/6/2015

Bottle Opener Presenting Day! 

Our bee opener successfully opened the bottle cap (as messy as it was)! Some of the soda ended up spilling across the table because I wasn't holding the bottle properly on the table...sorry table. It was very nerve-racking to test out a product in front of classmate, and I am glad our product didn't fail us on presenting day. The bottom part of the bee's mouth had already chipped away from testing, and it was difficult to gain a good grip on the cap's ridges.

Analysis of Bee Bottle Opener 

As I mentioned in my last post, the whole bee serves as a lever to open the bottle cap. By holding the bee vertically, we would push upwards and allow the fulcrum (top of the bee's mouth) to roll towards the other end of the cap. Meanwhile, the bottom of the bee's mouth pushed outwards and pulled the ridges up, loosening the cap and eventually opening the bottle. The torque we created on the bee from 1) exerting force ourselves (controllable) and 2) its distance away from the pivot point (fixed), was enough so that the fulcrum would move slowly and allow the bee's bottom mouth to pull the cap's ridges out.

Applying the cantilever equation, , where deflection = (FL^3)/(3EI), that Amy gave us
at the start of class, we can apply this to our bee. We couldn't change E (Young's Modulus) because we were asked to work with only Delrin, nor I, the area moment of inertia, because were were working in 2D on a sheet of Delrin. The force F that it would take to open the bottle cap wasn't controllable either, since it would take a set amount of force to pry open each bottle cap. However, we could control the length of our bottle opener, which is why our bee fits in the palm of our hands. The smaller the deflection, the less likely it would bend and break, and thankfully, our bee bottle opener did not crumble at the sight of soda bottle.

Reflection 

Over the course of this project, we had many iterations until we finally came up with the bee. My blog posts from earlier describes the process (with photos) that Olivia and I had gone through to reach our bee. If I could go back in time, I would have stopped ourselves from making so many mistakes in our iterations, so that we wouldn't used as much Delrin. :( If we could change our final design, I would 1) use the 1/4'' thick Delrin so that our bee could serve its function longer, and 2) enlarge the bee's wings so that it could be used as a handle to make it easier to hold.

Thank you for reading my blog (or skimming it if it was too long)! I'm glad that our first project is completed!