Introducing Parameters

When you create a part like the hollow cylinder of our "Getting Started" example, you often start by creating a sketch, then you create a pad by extruding the initial sketch, then you add other features to the created pad. The final document is made up of features which define the intrinsic properties of the document. Removing one of these features results in a modification of the document. These features are called parameters. Parameters play a prominent role in Knowledgeware applications. They are features that can be constrained by relations and they can also be used as the arguments of a relation.

In addition to these parameters, CATIA allows you to create user parameters. These user parameters are extra pieces of information added to a document.

User parameters are very handy in Knowledgeware applications:

  • They can be used to add specific information to a document
  • They can be defined or constrained by relations
  • They can be used as the arguments of a relation.
  • They can be locked to prevent user modifications.
Editing a locked parameter is not allowed. However, a parameter can be valuated by any type of Relation. The parameter value will be updated even if it is displayed as locked in the Specification Tree.

Parameters are created clicking one of the following icons:

The parameters are created using the Formulas Editor. To find out more about this editor, see Getting Familiar With the f(x) Dialog Box.
The parameters are created using the Parameters Explorer Editor. To find out more about this editor, see Getting Familiar with the Parameters Explorer.
The created parameters only apply to edges, faces and vertex. The editor is similar to the Parameters Explorer editor.
The Set of Parameters enables you to gather user parameters below a set.

A given relation may take as its arguments both types of parameters (intrinsic and user).

For the parameters to display in the specification tree, check the settings below:

  • From the Tools menu, select  Options>General>Parameters and Measure.
  • In the Knowledge tab, check the With Value and With Formula check boxes, and click OK if you want the parameters to display their values and associated formulas (if any.)
When working in a Japanese environment, check the Surrounded by the symbol check box under Parameter names.
  • From the Tools menu, select  Tools>Options...>Infrastructure>Part Infrastructure
  • Check at least the Relations and Parameters boxes in the Display tab, and click OK.