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Maya Z-up and Leg_3jnt_01 issue

Hey guys,

Has anyone try to create the “Leg_3jnt_01” component with Maya in z-up?
With Maya in z-up, you rotate the “leg_C0_0_jnt” guide 90 degree in X and build it.
The first two joint just stretch for some reason.

Any clue?

I’ve noticed this too. It happens specifically when the ankle guide locator has a greater Y-translation value than the root guide locator. The leg builds normally until the “connect” guide build step, where the chain2bones setup IK joint chain seems to get flipped -180 degrees along the X axis. It also rotates a random amount along the Z axis, though I haven’t tested whether or not it can also happen to the Y axis or not. Once this happens the same bug will occur on the “operators” guide build step on subsequent builds until you build a different module, which resets the connection data.
EDIT: Video of the issue (left version works, right version breaks. Both the final and WIP version are shown.)


Okay, I found a solution. It looks like forcing “ikHandle2” to be created using “ikRPsolver” instead of whatever solver you choose in the settings tab (i.e. “ikSpringSolver”) seems to solve the issue.

Yes I found also that workaround but it remove the extra flexibility the IKspring gives you.

For now am building everything Y-up and flipping it once build until I find a better solution.

What is the advantage of using the springSolver over the RPSolver in this instance?

You are right, maybe there is none because the “springAngleBias” seem not to be affecting the behavior at all which is the whole point of the springIK.

Maybe am missing something…