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Wire to RBD feedback in DOPs


Normally if a wire is constrained to an RBD, the rbd isn't affected by the wire at all. Which is annoying ... but I had an idea to get it to work. the wire solver can store the internal forces on the geometry. In DOPs I made a point force, the position is set to the position of the constraint and the force is the wire's internal (linear) force. I have put a sopnet in the dopnet to get the wire and the constrained point so I can reference them in the point force. It could be simpler with a python expression to get the position and force directly without going through the sopnet, but this is just a little test...

For multiple attachment points, I think a copy data node could be used to copy the point force data for each constrained point ...

hip file here


Wire to RBD feedback forces from Sam Hancock on Vimeo.

Comments

  1. Back in houdini 8 (and 9 maybe), this worked out of the box with just a rbd constraint >.< With the new solvers, stuff like rbd/cloth mutual interaction doesn't work.

    Great blog btw sam!!!

    ReplyDelete
  2. finternal (internal force) missing from H13. Any alternative?

    ReplyDelete
  3. hey Sam, great work. Could you share any example with multiple attachment points, lets say many wires on single geometry without having create a new point force for each one.

    ReplyDelete
  4. I don't think I ever made a multi point example, maybe the new finite element stuff will be better at handling this sort of thing?

    ReplyDelete
  5. This looks like what I've been trying to do for a necklace/pendant combination. Glad it's not just me who's found it tricky... And would love to hear if you've found a solution that works in 14. Thanks for the info :)

    ReplyDelete

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