How to stop SplineIK scaling the length of bones.

Support Animation and Rigging
1

Hi there,

SplineIK is for animating chains etc.

So, I would have thought one of the most important things would be that SplineIK does NOT scale the length of bones, because that will scale the length of chain links that are parented to the bones, giving you a chain that acts elastic as if made of rubber. Not good.

Well this is exactly what is happening to me. NO matter what I do, SplineIK is scaling the length of my bones when you bend the curve around (via curve points hooked to empties) and therefore ruining the realism of my chain.

Ticking ‘Y Stretch’ on the SplineIK constraint makes it less so, but doesn’t stop it (even this is odd, because you would have thought UNticking it would have this effect).

SO how do I stop this? I would be very grateful for any help,. thanks.

2

I tried a simpler version.

Unticking the ‘Y Stretch’ does indeed stop the bones stretching, but it doesn’t stop the bones compressing shorter when the curve gets bent. This bending/compression happens with all but the most minimal of bends in the curve. Any way to stop it?