Pose joints with spline IK curves

To manipulate the CVs of the spline IK NURBS curve

  1. Select the NURBS curve.
  2. Turn on Display > NURBS > CVs.
  3. Turn on Display > NURBS > Hulls.
  4. Select a CV on the NURBS curve.
    Tip: For easier manipulation of the curve, create clusters of the curve CVs. See Create cluster deformers.
  5. Do one of the following:
    • Select the Move Tool (hotkey: w) from the Tool Box.
    • From the Modeling menu set, select Curves > Edit Curve Tool.
  6. Drag a CV.

    This moves the spline IK joint chain.

To create a cluster deformer for each CV on the spline IK NURBS curve

  1. Select the spline IK curve.
  2. From the main menu bar, choose Select > Cluster Curve.

    This creates a cluster deformer for each of the spline IK curve CVs.

To twist and roll the spline IK joint chain

  1. Select the spline IK handle.
  2. Select Modify > Transformation Tools > Show Manipulator Tool.

    The twist and roll circular manipulators appear at the start joint and end joints of the spline IK chain.

  3. Do the following:
    • To roll the entire joint chain, drag the circular manipulator at the start joint.
    • To twist the joint chain, drag the circular manipulator at the end joint.
    • You can also adjust twist and roll by selecting the spline IK handle and entering values for Roll and Twist in the Channel Box or Attribute Editor.

To slide the joint chain along the curve

  1. Select the spline IK handle.
  2. In the Attribute Editor, select the ikHandle node tab.
  3. In the IK Solver Attributes section, turn on Root On Curve.

    This constrains the start joint of the spline IK handle to a position on the curve. It also provides an offset manipulator to slide the start joint along the curve.

  4. Select Modify > Transformation Tools > Show Manipulator Tool.

    The offset manipulator appears at the start joint.

  5. Do one of the following:
    • Drag the manipulator to slide the joint chain along the curve.

      If you drag the start joint to the end of the curve, the child joints move off the end of the curve in a straight line.

    • Enter values for Offset in the Attribute Editor to move the root of the spline IK chain along the curve.
      Note:
      • You cannot drag the manipulator past the ends of the curve.
      • If you turn Root On Curve off, the Offset attribute is ignored.

To translate, rotate, and scale the spline IK curve

  1. Select the spline IK curve, then select the Move Tool (hotkey: w), Rotate Tool (hotkey: e), or Scale Tool (hotkey: r) from the Tool Box.

    Use the manipulators that appear to translate, rotate, or scale the curve. See also Move objects and components, Rotate objects and components, and Scale objects and components.

    Note: If you created the spline IK handle with Root on Curve off in the tool options, translating, rotating, and scaling the curve does not translate the start joint.

Related topics

Parent topic: Use spline IK