Using Forward Kinematics

ascenari.gif (1364 bytes)

This task describes how to control the manikin's movements using forward kinematics with the available manipulators as well as the Undo/Redo command.

  1. In the toolbar, select the Forward Kinematics icon .
    Note that this icon must be unselected by clicking on it again in order to access another function.

  2. Select the manikin's part that you wish to move by clicking it with the left mouse button. Two arrows appear: one indicates the direction of the motion and the other indicates the rotation axis for the active degree of freedom.

  3. With the left-mouse button, drag the selected segment so that the mouse cursor follows the arrow. The chosen segment will move.

  4. By default, the movement exerted will be done according to DOF1 (Degree of Freedom 1), which is either flexion or extension depending on the direction of rotation.

  5. If you wish to change the active degree of freedom, select the right-mouse button in order to activate the contextual menu. Select, the desired DOF.

    It is often easier to move a segment when the direction of the viewpoint is parallel to the rotation axis.

  6. The best viewpoint to move the DOF1 flexion/extension is from a side view.


  7. The best viewpoint to move the DOF2 adduction/abduction is from a front view.

    The Quick View toolbar can be very helpful when using the forward kinematics command; manikins can be seen from many viewpoints.


  8. To reset the selected segment, select the right-mouse button to activate the contextual menu. Then, Reset.

  9. To reset the whole posture, select the Body node in the specification tree.

  10. With a right-mouse click, activate the contextual menu on that same segment and choose Reset.

  11. The manikin will take the default (standing) posture.


Head/Neck Kinematics Model Enhancement

The head motion wasn't natural while the manikin was looking at something located on the side.  In this context, moving the compass up and down in IK mode produces lateral movement of the head.

This has not been done on the head/neck model itself but on the respective range of motion of the neck and the head axial rotation.  In the new model, most of the axial rotation will be produced by the neck.  Therefore, the flexion of the head will be straighter up and down and no longer lateral even if manikin is looking at the side.


ascenari.gif (1364 bytes)It's important to note that old postures of the head saved before (with the old model) in catalog or on a MTP (MovetoPosture) can be more and less different but the focus point will remain the same.  This difference will be bigger for postures with high value of axial rotation.  This means that the manikin will look exactly at the same location but its head can be less inclined laterally.

Using Undo/Redo

The Undo command reverses (cancels) the last segment manipulation. Select the Undo icon in the main menu toolbar to execute Undo.

An Undo operation can also be undone. For example, you can restore the last posture applied to a segment with successive calls to Redo .

The images below illustrate the undo operation on a posture applied using the forward kinematics command.

Initial posture

Forward kinematics applied

First Undo applied

Second Undo applied

The Redo command repeats the last cancelled action. Select Redo in the main menu toolbar to execute.

A Redo operation can also be undone. For example, you can restore the last posture applied to a segment with successive calls to Undo .

Position after Undo applied

Position after first Redo applied

Position after second Redo applied