Week Eight 5/25/2017

During this week in lab, a new layout for the shrink wrap was implemented. Individual layers of the plastic were attached to both the bottom and top of the glider with scotch tape. This made production of the kite take less time, as the layers were not needed to be bonded together using the solderer used previously. This was effective because the previous design methods were slow and required great skill to implement.

Fig 1: The edges of this model are sealed with scotch tape at all seams, creating a stronger, quicker bond between sheets of polyolefin

Figure 2: Sealing "ribs" created by the soldering iron in order to seal the kite's two layers together

As seen in Figure 2, the "ribs" on the polyolefin are lines from where the solderer used in this case was not effective at sealing the edges. The temperature of the solderer was 168॰F, which is greatly reduced from what it had been during previous attempts. The group expected to see a greater efficacy of this technique at a lower temperature, but even at its best, melting the top and bottom sheets of polyolefin together is not effective. The bonds rip open when the kite is heat shrunk because the melted bonds cannot handle the tension.

The current flight ability of the kite can be seen below: 

The kite has flight with too shallow of an angle of attack, causing it to dive downward at a rather sharp angle. Weight at either end of the kite (specifically the back) has not made this angle of attack any higher (relative to the horizontal). It has only served to make the flight more unstable. 

Because of this instability, a fin on the back of the kite was constructed to give pitch stability to the glider. It is currently being tested for its usefulness in the final design.