Catapult Timeline

Catapult Timeline

by Mira Grcevich and Gabby Groff

References

"Catapult Physics." Real World Physics Problems. Real World

Physics Problems, n.d. Web. 07 Oct. 2015. <http://www.real-world-physics-problems.com/catapult-physics.html>.

Grcevich, Leah. (2015, September 28). Personal Interview.

"Mangonel - Physics of Catapults." Mangonel - Physics of

Catapults. Physics of Catapults, n.d. Web. 07 Oct. 2015.

<https://sites.google.com/site/physicsofcatapults/home/how-a-catapult-works-the-physics/mangonel>.

Mulhern, Bailey. (2015, September 25). Personal Interview.

Thank you for your time!

Overview

• Overall, this was an appropriately challenging learning experience unlike typical class projects
• This project showed us the physics we have been studying in a real-life application, which was a refreshing change
• Our group dynamic was great
• We can't wait to launch!

Findings

• After drilling holes in the top and bottom of the arm, as well as altering the angle of the basket upwards, we found that the launched projectile was able to surpass the 1.0m. wall
• The holes lessened the mass of the arm, and allowed for more energy to be transferred to the tennis ball, rather than lost in the movement of the arm
• The angle of the basket allows for the projectile to be sent on a path upwards when it initially leaves the basket, rather than immediately starting down

Process

Test Launch

Goal:

Materials

The Final Catapault

• Purchase necessary materials
• Cut PVC pipe to predetermined size
• Assemble the base
• Assemble support system for arm and fulcrum
• Attach holding basket to arm
• Attach the arm to its fulcrum
• Secure the bungee to the catapult
• Attach spring and rope as the release mechanism
• Drill holes in the base to lessen mass
• Evaluate the structure

• PVC pipe
• PVC connector tubes
• bungee cord
• spring
• rope
• cup
• power-saw
• motorized drill
• hot glue gun

• We ran a few test launches identical to the test launch that will be performed in class
• The projectile did not surpass the 1.0m. wall, as it had a relatively slow initial velocity, and began its motion on an immediate downward path
• So, we revised/improved our catapault accordingly...

Create a catapult with an original design that can launch a projectile over a 1.0m. wall when the catapult is placed 1.5m. from the wall

The Catapault After-Launch

Work Station

Criteria

Additional Photogaph

• Maximum mass of 1.0kg.
• Must be free-standing when in the loading position
• Must be triggered remotely
• The lever arm can be no longer than 0.5m. from the fulcrum and must be rigid

The Release Mechanism

The Model In Progress

The Model

Continued

Design Outline

Sketch of Design

• Mangonel catapult
• Potential energy is stored in tension in bungee cord
• The majority of that stored energy is wasted on the movement of the arm
• More energy is transferred to the projectile when the arm's mass is lower
• PVC pipe
• Tension device; in our case, a bungee cord