@Miquel I stayed up all night the other night trying to figure out what’s causing this upper leg flipping but wasn’t able to make much progress deciphering how the leg is set up as I’m pretty new to rigging in Maya.
I feel like the problem is coming from somewhere in the above nodes.
I’m reading in the Maya docs about the tendency of joints to flip on spline IK setups but I’m not sure where it derives it’s up or forward vectors from. I tried messing around with the Advanced Twist parameters but couldn’t find any settings that put the upper leg’s roll back in to Body space rather than Scene/World space.
Generally, the entire rig should fall under the umbrella of the World Control. Rotating or translating World should move the entire rig as a package without any impacts on twists or aim constraints. The way it behaves now is like it’s vectors are coming from Scene space instead of Body space.
I know it may be a while before this can get fixed in a release but in the meantime, does anyone know how to manually correct this? Are the nodes parented incorrectly? What is the actual cause?
I’m just giving the thread a bump since it was initially posted about two weeks ago with no insight posted yet as to what the cause of the problem might be and how to correct it.
So I noticed in moving the leg_r_root control around that the flipping was only happening in the skinned joint (thigh_r ), and not any of the rigged joints, at least not that I could see.
thigh_r is mgear matrix constrained to leg_R0_div0_loc_cnx_off
I deleted the mGear matrix constraint from thigh_r and parent constrained it directly to leg_R0_rollChain0 and the flipping no longer occurs. So I feel pretty confident that the flipping is not actually coming from the rollChain after all.
I’m going to study what’s going on with leg_R0_div0_loc_cnx_off to see if I can figure out if this is driving the flip.