About Adding Relations
Typically, you add relations by clicking Tools > Relations and using the Relations dialog box.
Additionally, you can add relations in the following ways:
Edit the relations file and add more relations.
When creating a feature, you can type an expression in the dimension box located on the dashboard. When editing a feature, type an expression as a value for the dimension.
When editing a dimension in the graphics window, double-click a dimension and type an expression as a dimension value.
Adding Relations to Different Types of Objects
You can add relations to different types of objects. The supported object types, listed under Look In in the Relations dialog box, are:
Part—Access part relations both in the Part and Assembly modes.
Assembly—Access relations in an assembly.
Feature—Access relations specific to a feature in the Part or Assembly mode.
Inherited—Access relations both in the Part and Assembly modes.
Section—If a feature has a section, access section relations in Sketcher while in the Part or Assembly mode.
Pattern—Access relations specific to a pattern in the Part or Assembly mode.
Skeleton—Access relations for a skeleton model in Assembly mode.
Component—Access relations for an assembly component.
Rules for Creating Relations in Parts
The following rules apply to creating or modifying relations in parts:
Driven variables can be as follows:
Dimensions in the part (d#)
User parameters in the part (parameter_name)
User parameters in features (parameter_name:fid_N or parameter_name:fid_feature_name)
Driving variables can be the same as the driven variables. In addition, you can use:
Reference dimensions from the part (rd#)
Evaluation feature measurements in the following format:
Rules for Creating Relations in Features
When you create relations in a feature, they are saved with the feature, and stay with it regardless of the model in which the feature is used.
Feature relations are evaluated after part relations and they are solved when the feature to which they belong is regenerated. Therefore, if a relation performs geometry evaluation (such as the distance between two points), it can give different results if used as a feature relation versus being used as a part relation.
You can modify existing model parameters by name from the feature level.