Home Technical Talk

Evenly distribute deformation across IK constraint? (rigging leaf spring)

polycounter lvl 5
Offline / Send Message
Rekov polycounter lvl 5
Is there any way to evenly distribute how much each individual bone in an IK constraint rotates?

The effect I am going for is a series of bones of a fixed length, arranged along the arc of a circle. The bones should straighten out as the spring is flexed, but I want them to still follow the arc of a circle, albeit one with a larger radius.

Instead, they deform unevenly, with the right side of the spring straightening first, and the left side remaining curved up until the very end:

The ultimate problem though is that this is kind of backwards. Ideally I want the armature to be 'driven' by the position of the axle, where moving the axle up and down causing the spring to flex, which in turn pushes the swing-bar at the end. Instead, this current set up, the swing bar controls the flex of the spring, which then moves the axle up and down. I'm not sure how to go about reversing that, but I would settle for first figuring out how to make the actual deformation look better.


  • poopipe
    Offline / Send Message
    poopipe high dynamic range
    I think I'd probably drive the bone positions with a curve .  Leaf springs are complicated beasts since axle twisting causes them to bend in strange ways.  You'd probably need to script some stuff to get it working

    If you can ignore the weird bits  You might have more success using two chains instead.
Sign In or Register to comment.