Directly Associating Data with a Feature

As soon as Annotations are available, Feature Checks and Datums can be built and data can be associated with those features. A user could potentially measure all the features on the part independently of the GD&T analysis process and then come back after the fact and associate the appropriate measurements with the corresponding Datums and Feature Checks. To associate data with a datum or a feature check just right-click on the feature in the tree and select Associate Points or Associate Clouds. This will clear the list of currently associated points and or point clouds associated with the feature, if any are currently associated, and associate the selected points or clouds with the feature. Once features have associated data they can be evaluated all at once by right-clicking on the feature checks and selecting Evaluate all Checks.

 

Point Associations by Proximity

Its important to understand that datum alignment is used when a single check has many features referenced within it. Take a position check on a bolt hole pattern as an example. If you are not aligned to the part SA will not be able to tell which point goes to which of the referenced holes. To solve this SA uses a proximity filter. It will subdivide the associated points and assign them to the corresponding feature based on proximity when the feature check is evaluated. This can cause problems however, if you are not closely aligned enough for the proximity filter to correctly associate the points.

GR-Features offer an alternative to this. Multiple GR-Features can be built and then referenced for a single GD&T pattern check. Because each GR-Feature has its own associations the GD&T evaluation can directly use this to identify which point are assigned to which nominal object.