Character Rigging | Yori | Part X
Updated: May 21, 2021
I'd like to thank my friend and Character Artist, Miki Bishop, for letting me use this character for this series.
Mechanical Arm Rig
Today we're talking about the mechanical arm rig on Yori's backback. This is a simple setup that can be built along with an FK system so you can toggle between them.
It's very similar to the Spline IK Twist from previous posts, check it out if you need a refresher! Just like the twist in the legs and arms, we're going to make a stretchy-stretchy node network with CurveInfo and MultiplyDivide.
HOWEVER, this mechanical arm isn't made up of stretchy parts (like Doc Ock's tentacles from Into the Spiderverse), but hard plastic-like materials. So when I first plugged in the stretchy-stretchy, the hand would separate from the rest of the arm when the controls were translated too far:
My solution was to add a Scale Limit to all the joints affected by the stretchy-stretchy network, and it looked much better:
You might be wondering, why go through the trouble of making the stretchy-stretchy network if you're going to add the Scale Limit?
Well, while the stretch doesn't look wonderful when the joint scale gets higher than 1.0, it does give the arm a bit of a cushion when the controls are smooshed together:
The setup has three chains:
I'm trying to document the testing process a bit more, I think there's valuable things to learn from my failures while I'm coming up with stuff!
Hope you enjoyed this week's tutorial and godspeed,
-Fefê