Creating a Deviation  

This task shows you how to create a deviation annotation on a part or product. This annotation is used in the Tolerance Analysis of Deformable Assembly workbench.
  • A deviation annotation represents a specified or measured point according to a statistics law.
  • The deviation annotation of an assembly component is contained in its annotation set:
    • For a leaf assembly component, deviation annotations represent the input annotations or initial annotations.
    • For a parent assembly component, deviation annotations represent the output annotations or annotations to be verified.
  • A deviation annotation is always associated with a datum reference frame.
  • This datum reference frame must be:
    • isostatic at least.
    • associated with the assembly component where the deviation is created.
Open the Tolerancing_Annotations_09.CATPart document.

  1. Click Deviation in the Deviations toolbar.

    Select a point or a vertex. For the purpose of this scenario, select Point.3.



    The Deviation Definition dialog box appears.

  1. Select the deviation datum reference frame, in this case Datum Reference Frame.3.
 

  1. Set Z as the normal direction.

  1. Click the Statistic Law tab to select and define the desired law.
    Six laws and their parameters are available: Normal, Uniform, Constant, Pearson, Poisson and Snedecor. For more information, refer to Statistic Laws.

  2. Click the Analysis tab to select and define the desired analysis.
    Two analyses are available:

    • Local: the deviation annotations are taken into account where they are defined only

    • Global: the deviation annotations are interpolated on the part or the product.

  3. Click OK. The deviation annotation is created.