Create auxiliary pivots
 
 
 

You can add additional pivot points to your FBIK effectors using auxiliary pivots. Auxiliary pivots allow you to transform your FBIK effectors from different points in 3D space to create specialized motions such as a foot roll during a walk cycle, the ball of a foot putting out a cigarette, a body spinning head over heels while flying through the air, and so on.

NotePinning auxiliary pivots has the same effect as pinning their parent effectors. For example, if you pin a FootEffPivot, the FootEff actually gets pinned—not the FootEffPivot.

To create auxiliary pivots

  1. Select the HipsEff effector and select Skeleton > Full Body IK > Go to Stance Pose.
  2. Select the effector for which you want to add a secondary pivot and then select Skeleton > Full Body IK > Add Auxiliary Pivot.

    A auxiliary pivot is created for the foot FBIK effector. The name of the auxiliary pivot is the same as its parent effector except for the suffix Pivot. Also, each subsequent effector is given a number. For example, the first auxiliary pivot for LeftFootEff would be named LeftFootEffPivot and the second auxiliary pivot would be named LeftFootEffPivot1.

  3. Select the auxiliary pivot, scale it as desired by setting its Radius value in the Channel Box, and then translate it to the position from which you want its parent effector to rotate.
  4. With the auxiliary pivot selected, select Skeleton > Full Body IK > Activate Auxiliary Pivot.

    Now when you transform the auxiliary pivot, its parent effector will rotate from the position of its active auxiliary pivot.

Example: Biped foot rolls

To create good foot roll behavior with auxiliary pivots when animating a walk cycle for your biped character, you need to create two auxiliary pivots for your LeftFootEff and RightFootEff effectors: one auxiliary pivot for the heel and the other for the ball of the foot.

  1. Select your LeftFootEff FBIK effector and then select Skeleton > Full Body IK > Add Auxiliary Pivot.

    A auxiliary pivot called LeftFootEffPivot appears at the position of LeftFootEff.

  2. Select LeftFootEffPivot, scale it as desired by setting its Radius value in the Channel Box, and translate it to the heel of your character’s left foot.

  3. With LeftFootEffPivot still selected, select Skeleton > Full Body IK > Activate Auxiliary Pivot.

    The LeftFootEff will now rotate from the position of LeftFootEffPivot (heel), producing a heel strike and downwards foot roll motion from the ankle.

  4. Select LeftFootEff and create another auxiliary pivot.

    A auxiliary pivot called LeftFootEffPivot1 appears at the position of LeftFootEff.

  5. Select LeftFootEffPivot1 and translate it to the ball of your character’s left foot.

  6. With LeftFootEffPivot1 still selected, select Skeleton > Full Body IK > Activate Auxiliary Pivot.

    The LeftFootEff will now also rotate from the position of LeftFootEffPivot1 (ball of the foot), bending the foot at the ball and producing a pushing off motion in the foot.

  7. Repeat steps 1-6 for the RightFootEff.