Skip to main content

Weekly Update: Week 7

Going into lab this week we had just about every big decision made. We knew the shape of the kite, a slightly modified delta kite with a dihedral angle, the material of the frame, bamboo skewers split in half down the vertical center, and the material of the sail, thin  plastic from typical grocery bag. The only thing we still needed to do was figure out how to attach a line and make it user friendly.

The challenge we faced here was that the sail is attached to the bottom of our kite. This makes attaching a line to the frame very difficult. To achieve this we would have to poke holes in the sail to send the line through. However, if the line were to move during flight, it could rip the sail more, thus decreasing the kite's overall flight.

Through testing we found that a single string attached directly to the kite did not offer the best stability. We also found that, for best results, the string should be attached slightly in front of (closer to nose) the center of gravity of the kite. If the string is attached too close to the nose, when the string is pulled it tends to fly straight back at the flier.  We tested several times to find the perfect placement.

Through further testing, we found that attaching a shorter string to the kite frame in two spots, close to nose and close to tail, and then attaching the line to that gives the best results. The kite stays in the air fairly easily and is easy to control.

To battle the issue of the sail ripping, we reinforced the sail with tape over the holes made by the string. 

Figure 1 shows how the line was attached to the kite.
Figure 1: Attachment of line to kite

Comments

Popular posts from this blog

Weekly Update: Week 2

This week's lab session was dedicated to research. We did not have our materials, thus we could not start building prototypes just yet. Instead we looked into background information. We found many sites that gave us key information on how and why a kite flies.  We also looked into technical kite terminology. This information helped us to understand why certain kite shapes acts the way they do. Through research, we found that the most successful indoor kites are based off of the Delta wing shape. This style of kite features a triangular shape. This shape allows the kite adjust to changes in wind. Figure 1 shows a an example of a Delta Kite. Figure 1: Example of Delta kite http://intothewind.com/delta-kites This shape maybe useful in our kite design. Our design is inspired by a flying bird. The Delta shape resembles a bird in some ways. A few modifications may be needed, but using this shape is definitely something to think about. ...

Weekly Update: Week 6

This week was focused on further improving our prototype. We kept the same shape of the frame, however we spilt the skewers in half vertically, to make the kite lighter. This allowed the kite to glide further. Figure one shows the current prototype Figure 1: split skewer dihedral frame Another thing we did this week was try different plastics for the sail. We thought if we tried a stronger plastic, the kite would be stronger and more resistant to damage. The plastic we tried was thicker and stiffer than the plastic we had been using to test our prototypes. Figure two shows a comparison of the two plastics. The thinner plastic (brown) is shown on the left and the thicker plastic (white) is shown on the right. This added unnecessary weight and caused the kite to not glide as far. As a team we decided that good flight was better than  strength, in this case.  We took the thicker plastic off and went pack to the original thinner plastic. This is ...

Weekly Update: Week 8

This week we focused on getting quantitative data. Over the term we have evolved our prototype. This resulted in having four versions. We wanted to test each one to see if our final design is really the best. To start we collected glide ratios for each prototype. We were surprised to see that one of our early prototypes glided better and further than our current prototype. The early prototype glided 15 feet while the current prototype glided only 9 feet. Because of this finding we decided we wanted to test each with a line attached. Just because a kite glides well does not mean it has good control in the air. through this test we found that our current prototype offers more control in the air. We believe this is due to its dihedral shape. The other prototype is flat and had no way of correcting itself when it got off balance. The dihedral shape offered more lateral stability. Taking both tests into account we decided that the current prototype is in fact the better of the two proto...