Fine Tuning the Motions with IK, FK

This section covers how to fine tune the actor with IK (Inverse Kinematics) and FK (Forward Kinematics).

ClosedWhat is IK

IK, Inverse Kinematics, refers to a process utilized in computer graphic animation. In this process, the parameters of each articulation, in a jointed flexible object (a kinematic chain), will be automatically calculated to achieve a desired pose, especially when the end point moves.

Basically speaking, IK is how the child node, as it moves, affects all the parents' position and orientation values.

Child node selected

Offsets of all nodes in the chain gets affected

ClosedHow to Use IK

Before you utilize IK to animate your actor, be sure that you have opened the 3D Motion Key Editor.

  1. Double click on the target actor.
  2. Click the 3D Motion Key Editor button. Alternatively, you may right click on the desired actor and select Motion Menu >> Edit Motion.
  3. Change to the tool in the 3D Toolbar.
  4. Select a body part (in this case, the right hand) by double clicking it on the dummy in the 3D view or by simply clicking it on the dummy graphic.
  5. Drag the axis of the gizmo on the 3D view.
Closed What is FK

FK, Forward Kinematics, is how the positions of particular parts of a model at a specified time are calculated from the position and orientation, together with any information on them of an articulated model.

To sum up, FK refers to the effect on the child nodes as the parent moves or rotates.

Parent node selected

Only parent's offset gets affected

ClosedHow to Use FK

Before you utilize FK to animate your actor, be sure that you have opened the 3D Motion Key Editor.

  1. Double click on the target actor.
  2. Click the 3D Motion Key Editor button. Alternatively, you may right click on the desired actor and select Motion Menu >> Edit Motion.
  3. Change to the tool in the 3D Toolbar.
  4. Select a body part (in this case, the upper body) by double clicking it on the dummy in the 3D view or by simply clicking it on the dummy graphic.
  5. Drag the axis of the gizmo on the 3D view.