Model Tension Cable in SW Simulation
Model Tension Cable in SW Simulation
(OP)
I am trying to analyze a tripod whose legs are connected by tension cables. I already know the pretension and stiffness values. I'm wondering what mechanism in Simulation to use to model them. I've tried using the spring connection and spring fixtures but both so far are looking for parallel faces for the end fixtures which I don't have. Does anyone know a better way or a way around this parallel faces issue? I've attached a picture so you can see the situation. The picture doesn't show too much detail for security reasons, sorry.






RE: Model Tension Cable in SW Simulation
Basically
if distance from point 1 to point 2 is less than length then
tension=0
else distance = original length of rope
endif
you could put this in series with a simple spring if you need elasticity.
Alternatively create a series of rods and join them appropriately, eg with UJs. That technique works better if you are worried about the dynamics of the rope itslef, rather than just the length constraint.
Cheers
Greg Locock
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RE: Model Tension Cable in SW Simulation
Thanks again for your help,
RE: Model Tension Cable in SW Simulation
TOP
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RE: Model Tension Cable in SW Simulation
-Cynthia
RE: Model Tension Cable in SW Simulation
Analyze this in Cosmos/M, not Simulation (motion simulation). Build a model with beam and truss elements. See Kinematics and stress in one FEA run. That model has a moving 4 bar linkage, a beam in which stress is recovered, and an over center spring. It is a simple model to build and quite appropriate for your tripod. Because this model used beam, truss and spring elements it runs super fast so you can do all kinds of load cases.
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CSWP
BSSE
www.engtran.com
www.niswug.org
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