topic Re: Pull requirement: lowest rank item even if it is not available yet in FlexSim Forum

Pull requirement: lowest rank item even if it is not available yet

LopezBuzo_AlfredoJesus — Sun, 20 Apr 2025 11:53:21 GMT

[ FlexSim 25.0.4 ]

Hello,

I have been having trouble solving the following issue:

I want to move articles to a floor storage in a specific sequence (in this case by rank of the boxes) from the queue beside it. This shouldn't be that difficult in a normal case. The issue is that the boxes arrive at the queue 2 at different times since some have to go through a QA process before getting to the queue 2. In that QA process some boxes are marked as broken and go to another floor storage and not to the "good" one.

As a result the not broken boxes arrive to the floor Storage in roughly the correct order. However in some cases a box at QA is bypassed by a newer box which didn't need a QA check. So the box order at the storage looks like: 1, 2, 5, 6, 9, 7... I need it to be 1, 2, 5, 6, 7, 9. Meaning, the ninth box has to wait for the 7 to arrive from the QA Process. This is for example the case at 1455.78 s.

The moving of boxes to the "reviewed Floor Storage" is done by a Box Outbound List. Besides that there is a List of all Boxes.

I think the easies way to solve the issue is to a create a "MeetsPullRequirement" label in the Box Outbound List which checks if the current box has the lowest rank among the not moved yet boxes and is not broken and use it as a WHERE query.

I tried creating this Requirement by writing a code. However, my coding skills are not there yet.

If somebody could help I would be very happy!Pull-Requirement for QA-Box-Check.fsm

Re: Pull requirement: lowest rank item even if it is not available yet

moehlmann_fe — Tue, 22 Apr 2025 06:19:37 GMT

A solution without too much coding would be to write the ranks to a global variable array. The list field can then just check if the BoxRank of the item is equal to the first value of the array. If a box is tested and broken, its rank is removed from the array and the back orders are reevaluated in case an item in the queue can now be pulled (On Process Finish trigger).

If an item is pulled, its rank also needs to be removed from the array. In the attached model I do so in the transport reference field.

pull-requirement-for-qa-box-check_1.fsm

Re: Pull requirement: lowest rank item even if it is not available yet

LopezBuzo_AlfredoJesus — Thu, 24 Apr 2025 21:18:08 GMT

Since I am working with the test version of FlexSim I have no access to a global variable. Can you think of a way to avoid the use of a global variable?

Re: Pull requirement: lowest rank item even if it is not available yet

moehlmann_fe — Fri, 25 Apr 2025 06:13:03 GMT

You can store the array in a label of one of the objects. In the attached model I use the inbound queue.

pull-requirement-for-qa-box-check-2.fsm