Wrong dashboard statistics when doing multiple pushes from a list

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felicity asked Oct 24, '23 felicity commented Oct 25, '23

Wrong dashboard statistics when doing multiple pushes from a list

I have a problem regarding the throughput number shown in my dashboard.

In the model, a separator splits each flow item into 55 items, then a trolley moves these items in bundles of maximum 20 items from queue3 to queue4 (I use a list with required value of 20). So every time the separator finishes one round of processing, there are 55 items in queue3 which are correctly presented in the dashboard. The trolley has to move back and forth 3 times to transport all 55 items to queue4. When this happens, the queue4 has 55 items in it, but the dashboard shows 58 as its throughput.

I'm guessing each travel also counts as a separate throughput but I'm not sure what's the logic here and how I can fix it.

I also have this problem where every time I link queue4 to any kind of storage it gives an error. I'm not sure if the error is relevant to this problem but any suggestions would be appreciated.

Software Version:

FlexSim 22.2.0

dashboards separator multiple pushes

dashboard-stats-test.fsm (98.3 KiB)

Answer 1 · 2023-10-24T09:08:55Z

Felix Möhlmann answered Oct 24, '23 felicity commented Oct 25, '23

The trolley is loading the same item twenty times. This one item is then given to the crane and when the crane unloads it to the storage, you are moving it, plus the 19 other items into the storage. Moving the first item into the storage again immediately after the unload finishes is what causes the error because some of the internal logic that fires when an item enters the storage has not finished yet, when it is moved again.

Load and unload activities expect a reference to a single item, which the label "transporteditems" is not in this case. You have to take care to either run the Load/Unload for each item individually or use the Move Object activity to move all at the same time. As I said, currently you only load/unload a single item and then move it again together with the rest in Move Object.

You can eliminate the Load/Unload and still have the trolley/crane travel to the correct location by using the Pick/PlaceOffset task type.

· 4

Jason Lightfoot ♦ commented · Oct 24, 2023 at 09:10 AM

As Felix described.

At the moment you have exceptions in the model which you need to clear which relate to the crane2 unloading and then trying to move the same object into Queue4, while it has already left and entered FloorStorage1.

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felicity commented · Oct 24, 2023 at 01:17 PM

@Felix Möhlmann Is there another way I can keep the load/unload tasks (to ensure accuracy in the crane state chart) and also move objects the same way the model is doing currently? Perhaps using a delay activity between the trolley unloading the items into crane2, and crane2 loading them?

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Felix Möhlmann felicity commented · Oct 24, 2023 at 02:26 PM

You can use the load/unload with a single item, that you remove from the array of transported items and handle separately. Then move the rest of the items with Move Object.

That way you unload all items at once without any movement inbetween but the initial location is still correct.

dashboard-stats-test-fm.fsm

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dashboard-stats-test-fm.fsm (96.3 KiB)

felicity Felix Möhlmann commented · Oct 25, 2023 at 06:45 AM

Thank you very much. this does exactly what I want.

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