I just bought a pair of arms from the unity asset store and imported them into blender, the IK seems to work just fine untill i use a Child of constraint on another bone(which is supposed to be a weapon) on the arm's wrist bone

the bone rotates but it wont move.

I'll leave a video of it right here, https://www.youtube.com/watch?v=jfLmG2sQ_10

EDIT: the wrist bone seems to follow the child WHEN i disconnect the wrists parent, but if i do that the IK doesnt work in general. Appreciate all help, thanks in advance :)

  • \$\begingroup\$ Can you tell us what you've tried to do to fix it, and what you're expecting (just to be explicit about it, since we can only assume what you want and people might assume differently). \$\endgroup\$ – MichaelHouse May 15 '16 at 16:18
  • \$\begingroup\$ Too be completely honest i have pretty much tried everything at this point, and ONLY disconnecting the wrist bone too its parent has worked but then it wont deform the right way and the results im expecting is something like in this video youtube.com/watch?v=xzLnkpBQUfA I want to be able to attach a gun /or anything for that matter and move it around and make the arms follow it accordingly \$\endgroup\$ – LynoHD May 15 '16 at 17:58

What you see happening is correct. The issue is you have two parents fighting. Lets call them arm parent and constraint parent, the arm parent connects the hand to the arm, this is a connected parent that prevents the hand from moving which is why the constraint parent cannot move the hand. When you rotate the constraint parent the hand can rotate as the arm parent doesn't prevent the hand from rotating.

The result you want is to add a child of constraint to the weapon making it a child of the hand. This way when you move the hand, the weapon will follow. When you turn off the child constraint, the weapon can be left behind. You then animate the position of the hand and the weapon will follow.

This answer gives an example of animating the child of constraint to pick up and put down an object.

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  • \$\begingroup\$ thats exactly what isnt working. I already have made the weapon bone a child off the arm. still it wont move, only rotate \$\endgroup\$ – LynoHD May 17 '16 at 18:26
  • \$\begingroup\$ In your video you have the hand a child of the weapon (the weapon being the big bone you move), not the weapon a child of the hand. The bone with the childof constraint is the child. \$\endgroup\$ – sambler May 18 '16 at 7:59

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