Outside Resource

For our outside resource, we talked to JT Wyrick, a fellow senior that took physics class last year. For his end of the year project, he also built a trebuchet. He gave a couple of helpful hints. The first hint he gave us was to make sure that we have enough weight. He said that when we scale our model up to the full size, it seemed to him that the weight didn't scale at the same factor as the size of the trebuchet did. A second hint he gave us was about the sling. He said that this is the most frustrating part of getting the trebuchet to work right. Unfortunately, he really didn't have any solutions to the problem of the string getting tangled and the projectile getting caught in the string. When we did the trebuchet battle, we really understood what he was talking about because of how windy it was. In the end, JT provided some good advice that we used when we built the final product.

BATTLE DAY 5/14

The trebuchet is 100% complete! Attaching the sling took a little longer than expected, but that is about it. Unfortunately, we really didn't have a chance to test it before the battle and hone in the aim and force of the launch. I think that if we had another day or two, we would have been perfect. I wouldn't say that it worked amazing, but it was not the worst either. If I were to give the trebuchet's performance a grade, I would give it a B-. All in all, we had a great time designing and building our trebuchet.

Work Day 5/13

I can not believe it, but our trebuchet is finally starting to look like a trebuchet. We put so much work into it our model, CAPA, and our final product over the last month. It is a good feeling to see something that you designed be completed. All we have to do before the battle it attack our sling. Overall, we really didn't run into any major problems with this build. It was amazing that it all came together the last day we had to work on it. We had all of the individual pieces built before, today was just the day to attach them all.

Work Day 5/10

Good progress was made today. I remembered to bring the fourth 2x4, so we cut that to the same length as the other three. We then screwed them together. All that is left is screwing them to the base, and hooking the sling and arm up.

Work Day 5/7

A lot of progress was made on building the trebuchet. We cut the boards for the base and screwed them together. We also started planning the dimensions of the tray that the projectile will slide in. We also worked on CAPA for a couple of minutes. I think that we are back on track towards being done by next week.

CAPA Day 5/6

Today we spent the day working on CAPA. No progress was made on building the trebuchet.

Work Day 5/2

Today we began cutting wood for the frame of the trebuchet. We also finalized our dimensions for the whole project. The base is going to be 1 meter by 60 cm. The height to the axle should be about 80 cm. The height to the top of the arm when it is straight up and down will be between 1.25 to 1.5 meters. We decided that we want to keep the same ratio of length from axle to length from axle to weight bucket as on our model. Just in case, we are going to drill more holes in the arm so that we can change the ratio if we need to.

Work Day 4/30

Today we tried to figure out our dimensions to our final trebuchet. As of right now, we are thinking of doing a base 60 cm. by 100 cm. The height is uncertain until we figure out how we are going to attach our weights to the arm. We wanted to start building the final one today, but the wood shop was out of the wood that we wanted.

Research Day 4/23

Today we did read a few chapters on the Physics Classroom website and watched a couple YouTube videos about Projectile at an Angle and Optimal Angle for a projectile. We also experimented a little bit more about where the axle should be located. Our farthest throw was about 4-5 meters. While working on this, we came up with some design changes for the final trebuchet. Some of these ideas are: a groove at the top of the arm for the string to fit in nicer, a weight bucket made with different materials, a locking mechanism, and wheels.

Work Day 4/22

Today we finished our trebuchet. We made a new sling since the original one was not working right. We also attached the sheet metal for the projectile to slide on. After working on this, we began to try to figure out what hole (position) the axle should be in to give us optimal distance.

Work Day 4/19

Today we attached the weight bucket and hooked up the sling. We did a few test trials to see how it worked. It took us longer than we expected to get it to work right. In most of the first 10 trials, the projectile went backwards. We corrected this by changing the weight and the angle of the nail that the sling hooks to.

Work Day 4/18

Today we were able to cut a metal rod that the arm is attached to. We also go about 90% done with the weight bucket.

Work Day 4/16

On our first day of work, we finished about half of the trebuchet model. We cut the base to the size we needed, and cut and attached the supports for the trebuchet arm. We also cut and bent a piece of sheet metal for our frictionless surface the the projectile will slide on.