Coppell STEM Trebuchet

Projectile Motion

The projectile motion will be held by a launch mechanism, which holds down the arm holding the projectile. Then, when that is released, the arm completes a 360 degree motion, but when the trebuchet reaches an angle of 43 degrees, the rope on the finger will slide off and the projectile will fly out of the sling. The sling will be made in the form of a blob and not a tight packaged sling because the projectile would get stuck in the crevices of the sling. The arm is moving in the air because of the potential energy turning into kinetic energy from the 150 lbs. weight. With this energy the projectile creates an arc of energy to be released from. When the full arc is complete, the arm with the finger is in the air, and the counterweight is on the ground, not touching the trough.

Design

The design of our trebuchet incorporates many aspects with portability, distance projectile has traveled, and the support of the force involved with our trebuchet.

To successfully design the trebuchet, we had to fully understand the math, physics, and the geometry needed in the design process. Trigonometry was also used to create the arm of the trebuchet and the physical length. We created engineering drawings to make the building stage go more smoothly.

Results and Analysis

The results of our trebuchet were not as predicted. Our trebuchet did not perform at it's full potential. This is mainly because our sling was a pouch instead of a sling which would catch the projectile before it launched. Another issue with the trebuchet is that the "wings" or sides of the trebuchet would hit the sides as we moved it out of the STEM lab, but that was fixed with a system of portable lift ups with the sides. Lastly, our biggest problem was that the rope would get the projectile stuck in the sling. we had to revise this edit by adding a bar in the middle to allow for two ropes to be hung in the center. This worked because we allowed for the rope to move more freely, and it didn't snag with only one piece of rope connected to the trebuchet. We chose to use 4 pieces of rope. Overall, our design could have been better, but due to the lack of time, we were not able to test our last installment of the bar with the trebuchet.