TENTACLE Spline IK Rig Issues

Hey everyone.

So, I’m having some weird issues with the rig I’ve made to control this octopus character’s tentacles.

basically, I have a deformation rig that has a spline IK modifier. Each arm is attached to a curve and then points on each curve are hooked to bones on a controller rig.

It seems to work really well as long as I only rotate the controller bones, like an fk rig. BUT whenever I move the controller bones past a certain distance, the mesh starts to go through itself in weird ways.

Does anyone have a better solution for rigging this guy?
AND / OR
Does anyone know what exactly is causing the mesh to deform in such an undesirable way?

I’ve attached my blendfile at pasteall http://www.pasteall.org/blend/43234
texture: http://www.pasteall.org/pic/106169

Thanks in advance.

I have not been able to pin down the weird deformations. I suspect it’s weight painting. Two armatures also adds a level of complexity to the rig. I’ll keep looking into it, but I’m feeling a bit under the weather today, so no promises.

I did make some tutorials on a simple FK/IK tentacle rig and also several on a more advanced setup. You can find them on my youtube channel, linked in my signature.

Good luck!

for me its not really clear what kind of deformation is weird for you and what you try to achieve.
If you could make a obvious visual description of your needs it would be much simpler to solve.

i would say the neck weights overlap with the spline ik chain bone weights and the y-strech of the splin ik constraint is uncheck.

Thanks DanPro. What an awesome tutorial. That rig has all the funtionality I was looking for, I just didn’t know how to make it.

I’d never seen curved bones and also didn’t know you could make an IK FK switcher in blender.