im not familiar with the book but if x>a would the load be off the beam? or is the starting point a and the ending point b, so that if x>b then the load is off the beam?
weeding out is good for two reasons i think:
1) engineering isnt always a cake walk. there is a lot of thinking and effort that has to be put into each design problem. if someone drops out of a class because it was "too hard" then good riddance. if you cant handle a difficult...
DaveViking-
its just for playing around. here is the site i used to get the basic design. i modified it a little.
http://www.io.com/~beckerdo/other/trebuchet.html#theory
i made mine in about 3 days (from lumber store to firing) and i used a normal 1x4 and ripped it down with the table saw...
pylko-
i dont know the force in the spring. my goal is to find out how much stress the arm can handle, and then use a spring accordingly.
thats the part i am confused about. uts, flexure modulus, youngs modulus, i dont know which to use or how to use it.
thanks for opining though.
also, i realize this is more of a dynamics problem with all of the rotation and forces and whatnot, but i was looking for more of a static solution. like when the arm is cocked and ready to fire, what stress can it withstand without breaking. from this, i believe i can "dynamicsafy"...
i appreciate your input, but the trebuchet is already built. so i can't really change the pivot design without rebuilding the whole thing. im entering my senior year at college so i should know how to do this but for some reason im drawing a blank.
Pivot []
[==============]
load [=======================] projectile
[==============]
{----5in----}
{---------8.5in--------}
{-----------------17in-----------------}
Everything is 3/4in by 3/4in northern white pine glued together and pinned with dowel...
