Graphical Force, Acceleration, and Velocity Analysis of a Trebuchet

Hi guys,

I am working on a project for my Kin/Dyn Class and I hit a road bump in doing my analysis for my project. For the force analysis there would be a force of 80 pounds from the counterweight. So I drew my arrow for that. Do I need to consider link three first or just do the graphical force analysis on link 2. The height of the trebuchet is 2.5ft. Arm: 3.4ft. Weight Link: 1ft



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Here is a picture of the force analysis.
[IMG]http://www.engineersedge.com/engineering-forum/attachment.php?attachmentid=1945&stc=1[/IMG]

Another issue I have is that I do not know my angular velocity. So I figured I find it by doing a Complex Vector Analysis. But, I am not sure on how to create my loop for the mechanism.


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