How are position constraints regenerated?

By default, when Abaqus/CAE regenerates the assembly, it regenerates all of the position constraints before regenerating other features that might depend on the position, such as partitions and datums.

However, if the position constraint uses an entity that was created by selecting from a part instance in the Assembly module, such as a face created by a partition or a datum axis running through two vertices, Abaqus/CAE changes its behavior and regenerates features in the order that you created them. As a result, partitions and datums that you created before the position constraint may not move along with the movable instance.

If you are working in the assembly-related modules, the Feature Options dialog box includes a Constraints field that allows you to control this regeneration behavior. For more information, see Tuning regeneration performance.