Successions
Successions are a special type of connections that are used to control the sequence between Actions and other SysML 2 elements. A succession asserts that an action can start execution only if its previous action has ended. Successions can be used to connect all Occurrences (Actions and Parts are Occurrences).
Creating a Succession connection
To create a Succession
1. On the System Structure Diagram toolbar, click the 
Succession button.
Succession button.2. On the diagram, click the first item for the succession and then click the second item. This creates a succession connection between two usage elements on the diagram.