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Seems simple but completely stumped. Watched tutorials, looked for similar questions and would really appreciate any help. I have 3 stacked blocks constrained to fold vertically as shown. The top block stays level. The hinges have to be offset obviously due to the block thickness and hinge points. No matter what I do it tries to fold in the opposite direction using RK since the offset picks the shortest route down as shown in the second pic. The blocks need to first pass over center (go up slightly) to fold the other way.Would really appreciate any help. enter image description hereenter image description here

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  • $\begingroup$ Sorry, I can't quite understand your question. Could you please clarify? $\endgroup$ Jun 7 '15 at 22:14
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    $\begingroup$ Thanks for responding. The second image show it folding the wrong way. It needs to fold with the block on the block hinge lines, not the way the armature wants to. The armature has to extend vertically on its way down by going up slightly first but it will only move straight down when you try to move it. I can't get the RK to go in the opposite direction to follow the correct block fold. $\endgroup$
    – Mike
    Jun 7 '15 at 22:52
  • $\begingroup$ I'm a bit out of my comfort zone here; I've not tried much by way of animation, but I'm wondering if it's possible that somewhere along the process you introduced rotation in your mesh, or in the bones, and failed to apply the rotation? $\endgroup$
    – brasshat
    Jun 8 '15 at 2:43
  • $\begingroup$ I think I understand but I don't think so. Maybe someone could try duplicating the problem? It seems so simple. Just want the blocks to fold flat vertically but it requires the control bones to go past vertical. I've tried limiting bones and blocks many ways but the lower bone always overrides $\endgroup$
    – Mike
    Jun 8 '15 at 12:36
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Try this:

create the first lower bone, then extrude 3 times, rotate the 4th bone 90 degrees, then ( in edit mode) slightly move the junction point between the second and the third bone in the Y axis, toward the direction you want the chain to bend. Another way is to check the bone's roll: in the armature tab - display - set to view axes, then trim the bone's roll until the rotation you want is on their x axis with positive values.

You can also add limit rotation costraints to the bones for having them moving only in one direction.

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  • $\begingroup$ Thanks. Is there anyway you might be able to duplicate the setup? I'm hoping that it would take about a minute for someone that knows how. I'm still a newbie, lots to learn in Blender and had no problems with complex meshes etc but this seems so simple. How do I limit bone rotation to one direction btw? $\endgroup$
    – Mike
    Jun 8 '15 at 12:40
  • $\begingroup$ Just select the model and the armature, shift D to duplicate, shift D X to duplicate and move on the X axis. To limit rotation or other interesting stuff go to pose mode, select the bone, in the properties panel select "add costraint to bones, select limit rotation, set the values (default mode is in 360 degrees, negative values are OK). Search for Nathan Vegdahl tutorials for advanced rigging, he's the number 1! $\endgroup$ Jun 8 '15 at 14:04
  • $\begingroup$ Tried all of the above now, had already watched hours of tutorials and watching more since and hours of manipulating limits, constraints, plus I've rigged other things that seem far more complex. This is like a brick wall. Limiting rotation doesn't work. Can someone try doing this and send a file if it works? Surely it can't be this difficult. The problem is specific. It relates to a limited rotation where Z has to start positive to start block rotation and then go negative. I have another picture to make it more clear but can't add to this thread as far as I can see. $\endgroup$
    – Mike
    Jun 8 '15 at 17:44
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since your objects are solid and not mallubles(like animal flesh), it is needed another joint, in the bending portion. if there is a problem with distortion of the object/mest joint, then the bending bone influence to that part of object/mesh must be zero/disabled.

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