kineFX realistic shoulder weirdness

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Joined: 5月 2021

I've been working my way through trying to set up a rig with KineFX, following along with various sideFX tutorials, the elephant etc. which has gone ok, some struggles but I got it working.

Last thing I did though was put in the realistic shoulder vop, got that working after some fiddling about. I'm not quite sure about my joint rotation axis and how they're meant to be, I tried to copy from what I could see in the Minhea Stoica Animation Cleanup video but for whatever reason, my clavicle lookup needs to be reversed or the shoulders goes down instead of up. I assume something isn't set up quite right. There is also a slight roll/pop if you pull the hand control off of or away from the IK chain. don't know how to get rid of that.

anyway, where I got stuck is once I put the realistic shoulder in, I get some very funky behavior on the legs. Left leg now has the pelvis rotating as I move the foot up, right does not. I turn the realistic shoulder off, everything is normal.
(also had to turn off compute transforms for output for the vop or it throws in an extra right leg and everything goes nuts)
the pelvis rotation was a neat accidental 'feature' but I don't get what's going on here and why one leg does and the other doesn't, and why the shoulder vop starts messing with the legs? I've checked all namings and groups. If anyone feel like having a look I'd be very grateful, any tips or feedback on this setup from someone who actually knows what they're doing would be most welcome, I feel like I'm winging it most of the time here, it works but i don't know if it's right.

hip file attached
many thanks /S

char_rig_v012_stripped.hiplc (543.6 KB)

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Joined: 10月 2019
what version of Houdini are using? I just had a look at your scene in Houdini 19.5.605(latest production build) and everything seems to behave as I would expect. The only thing I can reproduce is the need to provide a negative clavicle lookup axis to the realisticshoulder VOP. I also see that you are using the realisticshoulder 1.0 - we have built a 2.0 version since then which fixes a couple of things. If you are on 18.5 however, you will not have access to the 2.0.

One thing I can suggest is trying to set the scaleinheritance to 0 instead of 1. As to what this does, it determines the behaviour of the child joint when its parent gets scaled - it is used when computing the localtransform.
Here is a list of what each scaleinheritance mode does:
- 0: simple inheritance
- 1: child doesn't scale with the parent local scales, but local translation is scaled
- 2: local translation is scaled as before but parent local scaling is also reapplied by the child in local space
- 3: local translation is not scaled, but parent local scaling is reapplied by the child in local space
- 4: child completely ignores any parent local scaling

Just to confirm:
Left leg now has the pelvis rotating as I move the foot up, right does not. I turn the realistic shoulder off, everything is normal
this happens when you translate the leg_ctrl_R via the RIGPOSE_ARMS_AND_LEGS, correct?
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