Creating Curve Tangency Joints

You can create a curve tangency joint to constrain two curves from the same body to maintain contact at a single point. A sliding or rolling (translation and rotation) along one curve results in an equivalent translation or rotation along the second curve.

This task shows you how to:

See Also
About Joints

Specify the Definition Properties

  1. From the Mechanism section of the action bar, click Joint .
  2. In the dialog box, select Curve Tangency from the list of joint types.
  3. In the Definition section of the dialog box, select the two curves between which to create the joint.
    1. Click the Curve 1 box and select a curve associated to a body geometry in the work area.
    2. Click the Curve 2 box and select a curve associated to a body geometry in the work area.
    The name of the two curves appear in the corresponding boxes.
  4. To create the joint using a new curve:
    1. Click and select Create new Curve.
    2. In the dialog box, define a new curve.
    3. Click OK.
    The new curve appears in the tree and is listed in the box.
  5. Optional: To modify your selection, do one of the following:
    • Click and select Clear selection.
    • Select another element in the work area or in the tree.
  6. Select the tangency mode to specify the motion and adherence between the two curves.
    • Click Sliding to create a sliding joint with no adherence between the two curves.
    • Click Rolling to create a rolling joint with perfect adherence between the two curves.

    You can create sliding or rolling joints only between two elements that move relatively to one another.

  7. Select a mode to determine the relative direction of the curves.
    • Click Identical for the tangent lines of the curves to be parallel at the contact point.
    • Click Opposite for the tangent lines of the curves to be opposite at the contact point.
  8. Optional: If you selected the Rolling tangency mode:
    1. Specify a value for the position offset of the first curve.
      The value of the position offset for the second curve is specified automatically based on the position offset value of the first curve.
    2. In the Motion State box , select which curve to use in order to determine the offset of both curves.
  9. Optional: If you selected the Sliding tangency mode, specify a value for the position offset of each curve.
  10. Optional: In the States table, specify values to control the joint motion. To do so, in each row:
    1. Select the Lower limit check box to enable a lower bound in a specific direction.
    2. Select the Value check box to enable an initial value.
    3. Select the Upper limit check box to enable an upper bound in a specific direction.

    Notes:
    • Each row corresponds to a translation or rotation degree of freedom. The number of rows depend on the joint type.
    • If the lower and upper limits are not applicable, no check box appears in the corresponding row or column.

  11. Optional: Specify a value, as well as upper and lower limits for the curvilinear distance of the two curves.

Edit the Joint

  1. To edit a joint, in the tree, do one of the following:
    • Double-click a joint.
    • Right-click a joint and select Definition from the object menu.
  2. In the dialog box, edit the joint parameters.
  3. Click OK.

    Note: To modify the general properties or graphical properties of the element, right-click the element in the tree and select Properties. For more information, see Displaying Properties.