I am looking at a Finite element problem which I dont know how to solve or what method is used best.
The mechanism in question consists of two rigid links interconnected by a hinge in the origin of the coordinate system. The left bar is rigidly connected to the outside world the other one had a rotational DOF, theta. On top of the two rigid links is a linear elastic material that will deform under the application of force F. At some point the resistive force of the material will counteract the external force. (So basically a FEA with two diriclet boundry conditions of which one is a function of theta).
I am looking for an analytical expression for theta that will show its relation to the externally applied force. What approach should i apply? Or does somebody know a problem that is similar to this one that i can look into?
Thanks in advance!
This all depends on what level of simplification you want to consider.
If you consider a 2D elastic material, with height and depth, you need to take into account Youngs modulus and a Poisson ratio.
If however, this is simply a 1D representation problem, the entire elastic bar can be represented with a torsional stiffness (lets call it "k"). Then F*L*cos(theta) = k*theta or if theta is relatively small F = k*theta/L. The FE textbook "Nonlinear Finite Element Methods" by Peter Wriggers goes through an example like this in detail somewhere in the first 10 pages.
I hope this helps.
Kevin thank you for your answer
That is somewhat to simple, maybe the question wasn't that clear enough. I also need to know what the nodal displacements of the material are when subjected to a force F while the connection to these two bar imposes a displacement constraint for the underside of the material. So im trying to go much deeping into the dynamics as to what you propose.
If the right bar would be there this would be something like a beam problem even, very simple, but due to the added constraint the problem complicates.
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