Fix On Constraints

ascenari.gif (1364 bytes) The Fix On Constraint constrains the segment in orientation and in position (or only in orientation or only in position) at its current position according to the manikin referential or a given object.
  1. Move the manikin's hand (end effector) to a desired position in space in relationship to an object.

  2. In the Manikin Constraints toolbar, select Fix On.

  3. Select a manikin segment.

  4. Select an object; in this example, the box.

  5. Move the box away from its constrained position. The unresolved constraint is represented by a line with two stars (one on the segment, one on the box).

  6. Select the Update command to update the constraint. The end effector moves to the constrained position relative to the box location.


By default

  • The name of the constraint is ConstraintX where X is an incremental number.
  • The segment is constrained in position and in orientation. The position and the orientation of the segment is constant relative to the object; it cannot turn or translate.
  • The constant priority is 1.
  • The constant is activated.
  • The user has the the ability to reset the target of a fix or a fix on constraint.

Editing default properties

These default properties can be edited in the Constraint Properties dialog box. To access this dialog box do one of the following:

  • In the 3D view, double-click on the constraint.
  • Double-click on the constraint in the specification tree.
  • In the 3D view, right-click on the constraint and select "Definition..." in the contextual menu.


Name: Accept the assigned default name or rename as desired.
Manikin: You may use the manikin originally selected or, in the 3D view, select a new manikin.
Segment: Shows the selected segment. The combo box allows you to select the right or left side of the body for the current constraint. The control is disabled when the current segment is independent of the body side, i.e., the head. If the arm was selected instead of the hand, if the MoveToPosture changes, the update will not modify the constraint.
Object: The object in the 3D view that shares the constraint with the segment.
Type: Can be "Position and orientation", "Position", or "Orientation".
Priority: The priority is in terms of relative weight between the constraints. In a multi-constraint environment, a constraint with priority 1 will be given the most weight, and a constraint with priority 4 will have the least weight. These relative constraint weights will be considered by the software if the following conditions are true:
  • There must exist at least two active constraints on the manikin;
  •  These constraints must be on different kinematic chains;
  • The system must find no solution to resolve all constraints together.
Passing Criteria: Set a criteria that defines the maximum allowed distance between the segment's end effector and the target object.
Result: Shows the actual distance between the segment's end effector and the target object. The text "Success" or "Failed" is displayed depending whether the distance (length of constraint) is superior or inferior to that amount.