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Help  Obi Wire with more tension than rope
#1
Is there a way to really tension the rope within the obi solver or anywhere to make the rope be closer to a bendable wire/rope? It currently has too much flex and bounce for what I need it for, and need it to be able to flex and have the gravity of a rope, but not so fluid. I am also not looking for it to be rigid like the rod, a good middle ground between these 2 is what I am looking for. I have tried turning the substeps up quite a bit, and this does not get rid of the fluid movement enough and make the rope rigid enough with more tension for my needs. 
Thank you
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#2
(14-04-2021, 04:26 PM)Rembo Wrote: Is there a way to really tension the rope within the obi solver or anywhere to make the rope be closer to a bendable wire/rope? It currently has too much flex and bounce for what I need it for, and need it to be able to flex and have the gravity of a rope, but not so fluid. I am also not looking for it to be rigid like the rod, a good middle ground between these 2 is what I am looking for. I have tried turning the substeps up quite a bit, and this does not get rid of the fluid movement enough and make the rope rigid enough with more tension for my needs. 
Thank you

Hi there!

I can't really picture the kind of rope you want from your description, sorry Triste. You mention that you want a rigid rope, using more substeps will take care of that as it will allow the solver to reach lower constraint compliance (lower compliance = more rigidness). You can always increase the compliance parameter of the rope0s distance and bend constraints if you need it. For instance, you can make a completely inextensible rope that's very easy to bend (low distance compliance, high bend compliance), or a very stretchy rope that's almost impossible to bend (high distance compliance, low bend compliance)

Maybe all you need is to increase the solver's damping parameter. This will simulate air drag, making the rope lose energy more quickly and come to a rest faster. Maybe this is what you refer to as "fluid movement".

If you could provide a reference video of something in real life that's close to what you need I can help you find the parameters that mimic it.

cheers!
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#3
(15-04-2021, 08:17 AM)josemendez Wrote: Hi there!

I can't really picture the kind of rope you want from your description, sorry Triste. You mention that you want a rigid rope, using more substeps will take care of that as it will allow the solver to reach lower constraint compliance (lower compliance = more rigidness). You can always increase the compliance parameter of the rope0s distance and bend constraints if you need it. For instance, you can make a completely inextensible rope that's very easy to bend (low distance compliance, high bend compliance), or a very stretchy rope that's almost impossible to bend (high distance compliance, low bend compliance)

Maybe all you need is to increase the solver's damping parameter. This will simulate air drag, making the rope lose energy more quickly and come to a rest faster. Maybe this is what you refer to as "fluid movement".

If you could provide a reference video of something in real life that's close to what you need I can help you find the parameters that mimic it.

cheers!
I'm looking for more like a Bridge Cable, the really thick cable that is made from wrapped smaller wires. Wire Rope
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#4
(15-04-2021, 03:21 PM)Rembo Wrote: I'm looking for more like a Bridge Cable, the really thick cable that is made from wrapped smaller wires. Wire Rope

Using more substeps and tweaking bend constraints (http://obi.virtualmethodstudio.com/tutor...aints.html) should get you pretty close.

I'd suggest using 6-8 substeps (in the ObiFixedUpdater component), then setting bend compliance to 0.005 m/N (in the ObiRope component)
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