I have created a partial biped rig (just hip and left leg). Blend file attached.
However, when I use a bone to control the bone roll, the rig gets all screwed up and skews badly around the hip.
I am using David Ward’s alien rigging technique from Blendercookie.com
what is the correct process to control knee roll?
testrig.blend (379 KB)
You need to set the ‘chain len’ to the number of bones you want the ik constraint to affect, leaving it at 0 tells blender to affect all the bones in the hierarchy. Since the hip bone is the top most bone, it’s affected too. Set the ‘chain len’ to 2 for the bottom leg bone and 1 for the upper bone.
You could actually get rid of the ik constraint on the upper leg bone, and set the ‘pole target’ of the remaining ik constraint to be the knee bone and adjust the pole angle to be -90…
Randy
Thanks Randy.
I got rid of the IK constraint on the lowest bone then made chain length 3 and then applied a pole target as the knee with -90 as the angle. Works like a dream.
BTW Which river is your van beside?
I’m sorry, I made a mistake. By default, my computer opens .blend files with 2.49 and I didn’t notice the constraint on the controller bone, remove that one as well. After reading your reply, I opened the file in 2.55, saw what was going on and fixed it up, see attached file…
Randy
testrig.blend (342 KB)