======Development======
Construction on the model trebuchet has begun.\\
{{:start:classes:principlesofdesign:pumpkinchunkin:start:photo_6_.jpg?750|}}
====Design====
The final design can be found below\\
{{:start:classes:principlesofdesign:pumpkinchunkin:start:trebuchet_Final.png|}}\\
{{:start:classes:principlesofdesign:pumpkinchunkin:start:cart_final.png?200|}}
{{:start:classes:principlesofdesign:pumpkinchunkin:start:cart_outside_final.png?200|}}
{{:start:classes:principlesofdesign:pumpkinchunkin:start:front_view_final.png?100|}}


Here are some links that we found to help us research our trebuchet design.

[[http://thehurl.wikidot.com/trebuchettypes:faka|Floating Arm King Arthur]]\\
[[http://www.youtube.com/watch?v=-l4-_CI10xM&feature=player_embedded|Youtube video of FAKA]]\\
[[http://members.localnet.com/~lorilee35/theory.html|Theory of Trebuchets]]\\
[[http://www.algobeautytreb.com/trebmath35.pdf|More Trebuchet math - First couple pages are really important!!]] Pages 4 and 5 are the most basic calculations. A 1000lb counterweight (100x the 10lb pumpkin) requires a 10 foot trebuchet. Or rather, the counterweight has to be 10 feet above the ground. A 750 lb counterweight (75x the 10lb pumpkin) requires a 13.33 ft height. 

[[http://www.youtube.com/watch?v=zrsz5P3Sjkg|2011 2nd place Trebuchet Winner, Floating Axle/Arm design]]\\

====Kinetic Modeling====

Using the program Algodoo, we have been working on optimizing the parameters of our trebuchet.

[[http://www.youtube.com/watch?v=08zuy6G4MH0|Here]] is a video of a sample launch.

This launch was approximately 230m, with a 115kg counterweight and a 2 kg payload. 

{{:start:classes:principlesofdesign:pumpkinchunkin:start:punkin_chunkin_algodoo_simulation_upgrade_1.png?1000|}}
{{:start:classes:principlesofdesign:pumpkinchunkin:start:punkin_chunkin_algodoo_screenshot_1.png?500|}}
{{:start:classes:principlesofdesign:pumpkinchunkin:start:punkin_chunkin_algodoo_screenshot_2.png?500|}}

====Stress Modeling====
Stress and Displacement analysis for the axle holding the arm and counterweight. Here, a foot long piece of 2in diameter steel with a 1000 pound force applied at the center is simulated. Note that all displacements are tiny, and stresses are an order of magnitude below yield strength. \\
{{:start:classes:principlesofdesign:pumpkinchunkin:start:Stress.png|Stress}}\\
{{:start:classes:principlesofdesign:pumpkinchunkin:start:Displacement.png|Displacement}}