question

The Event-Triggered Souce creates another token when the AGV arrives back at it after loading items from Queue1. Since more items enter Queue1 before the task executer arrives at Queue2, the load tasks for those items are generated earlier than the unload tasks and are thus also executed earlier.

You have a number of options to influence the order in which the operations are done:

- Don't use an Event-Triggered Source and instead use a single persistent token that loops through the process flow.

- Use a Resource or Zone to limit the number of tokens that give tasks to the AGV to one at a time.

- Do the same by making all tasks part of a single task sequence which has to be finished before another one can be started (except when preemption is used). Note that you would have to adjust the task executer/task sequence reference in the activities.

Out of those three I would suggest to use the first option, since the other two result in an ever increasing number of tokens because, as mentioned, the AGV in fact arrives at NN1 twice per cycle. The other two are mostly mentioned as reference for how task executers can be controlled through Process Flow as well.