wired DOP problem...

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in a relative simple setup for metalbending my DOP make problems. Starting with not desired movement of the object. Would you mind to have a look to the hip, please, and give me some tips (advice)? I just overlooked something I think... Dont find it quite now,

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metal_bending.hip (805.9 KB)

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Follyx
in a relative simple setup for metalbending my DOP make problems. Starting with not desired movement of the object. Would you mind to have a look to the hip, please, and give me some tips (advice)? I just overlooked something I think... Dont find it quite now,
The wrangle you use to set the constraint_name and constraint_type attributes should be set to run on primitives and not points. I also changed the constraint to a bullet soft constraint since you said bendy metal and changed to expression on the enable solver to enable just once and emit one cube just for testing purposes and I also used a wrangle to set the name attribute on the bottom constraint anchor points to be empty so they become world-space anchors. Hope this helps. Oh, I also used the convertline SOP to create the correct accurate restlength attribute for the constraint primitives, which is needed for the soft constraints to behave.

added a version with plasticity on
Edited by traileverse - April 30, 2021 03:11:50

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metal_bending_01.hip (816.7 KB)
metal_bending_with_plasticity_01.hip (832.4 KB)

hou.f*ckatdskmaya().forever()
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yep, I forgot that... its ore comfortable with a softconstraint, right - but I want to use the hardpinconstraint for laborating, maybe updating the constraints via a sopsolver, I will see and post the result. Thanks anyway miccetro.
Good times and keep healthy
Edited by Follyx - May 1, 2021 04:01:25
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Also your setup is straightforward and pretty standard, I want to go with hardconstraints for learning purposes. Nevertheless a good answer ;-)
The first problem in my setup is that the bendend object tend to go back to its initial state. I grabbed the initial constraint, copy the primintrinsic "packedfulltransform" - the transfomationmatrix from the packed pieces onto it. In my sugggestion the sopsolver should send it to the rbd solver for the next step. So it should bend more and more. Unfortunately it goes back into its original position. Like there wouldnt be a sosolver and/or the constraints are totally wired. Why the constraints are bending back to its original position instead to bend more and more. If the last state of the constraints is the maximium bend state and the new origin constraints are already bent (this one I changed with the copied transforms from the bended geo), from where the rbd solver get its information to use other constraint states instead of the new initial state?
Edited by Follyx - May 4, 2021 03:52:12

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metal_bending_02.1.hip (1.1 MB)

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