September 2, Wednesday

We decided to enhance the functionality of the blimp by adding a speaker to allow for a one-way communication. The additional mass of the speaker was not an issue since the lift of the balloon was much greater than the weight of the components it was carrying. In order for the balloon to hold up the speaker, the Mylar must be strong enough to not tear. Since the speaker weighs a hefty ~90g, we felt that it was risky to simply tape it to the bottom side of the blimp as it might tear the Mylar. Hence, we chose to use the seams to hold up the speaker as they are reinforced with more layers of Mylar. We decided to carry out a few tests to get a rough estimation of its strength.

We used 2 new pieces of Mylar and double sealed them to imitate our double sealed balloon seams. Then we used a hole-puncher to create the holes.

 

 

For our first test, we attached 115g of object to the hole and left it to hang freely for 10 minutes. The hole did not appear to deform much.

Next, we attached 240g of object to the hole and left it to hang freely for 2 minutes before the string came loose. At a much shorter duration, the deformation was already larger than the previous test.

Since we aim to use 4 holes to support the speaker, each hole would have to support a maximum of 25g. These tests prove that the strength of the holes are sufficient enough to withstand the weight of the speaker.