My Universal Robots UR5e program picks a rigid molded spacer, places it and advances the pocket during tray-to-tray transfer in a workshop transfer test station.
Clean runs work.
After a stop between actions, the saved pocket sometimes doesn't match reality.
We've 67 planned, and I want recovery sorted before normal production depends on it.
Where does the index advance in your trace, relative to placement confirmation? Start with the sequence you have, not where the number ought to change.
The trace shows my index update occurs before placement is confirmed. That means the retained number can identify an intended next pocket without establishing that the preceding transfer completed.
Use an offline stage model to distinguish transfer progress from confirmed completion. Your integrator should define reconciliation between retained state and physical tool and pocket conditions, including what happens when those conditions are unknown.
@TheoAli0236 Updating a stage after an action doesn't eliminate the interval between the physical event and persistence. An interruption there can leave the saved stage inconsistent with reality.
You're right; saving stages alone doesn't guarantee recovery. The saved stage guides reconciliation, and the physical conditions still need confirmation before an approved next action.