I am pretty new to bender and have been attempting to set up a robot neck, made from a currigated tube. I need it to fold down on itself and stretch away from the body, while bending also allowing to move freely for the head.
I currently have set up three bendy bones. One anchors the base of the neck to the body, and one anchors the head to the top of the kneck.
My current issue is that when I bend the neck and strech it, a part of the Tubes Mesh divides and reveals gaps. I instead need it to stretch as to not show any gaps.
The Image on the LEFT shows the issue my Mesh has when stretching/moving the Bbone.
I assume this issue is about the Mesh rather than the bones. Any Help with how to solve this would be amazing! NOTE: The Pipe was created by chreating one ring of the mesh, then applying the array modifier.
FINALLY: One other quick glitch i keep having with the BBone is What you see on the RIGHT IMAGE.
Its suddenyl twists, but only in this exact position. How can i stop this happening, as it glitchs the Mesh!
Yes. It is someplace where the mesh has ripped vertices.
I assume the rip isn’t visible in rest. You should probably locate the rip in edit mode (“select non manifold” operation, or select vertex in weight paint then tab to edit, should make this easy), then select both edges of the rip, and merge by distance, with a distance of 0. This has the potential to change other things going on with your mesh, but should usually be best. If it’s not okay, the thing that’s important is that both sets of vertices that occupy a particular rest position have identical weights, then it won’t rip in pose.
With a symmetrical mesh, it’s hard to be sure that that the twisting issue isn’t appropriate. But, I have consistently seen interpolation errors involving twist when using b-bones. I see these when rotating the bone through the armature’s +Z axis, and I think what’s going on is that the b-bone is using a spline with armature +Z up tilt to create the twist. You could consider rotating the armature’s axes (like in “origins only” mode) and see if that helps. I tend to use spline IK in preference to b-bones for this kind of structure, for a variety of reasons, one being that I can control the “tilt up” axis to make sure that I can get good interpolation in the orientations I need. But spline IK, especially with tilt control, is a bit more tedious to set up than b-bone.
