topic Re: waiting in Queue untill the desired quantity reached in FlexSim Forum

waiting in Queue untill the desired quantity reached

TalHzf — Mon, 13 Feb 2023 10:21:14 GMT

[ FlexSim 22.2.0 ]

Hi all,

I am doing a simulation for a Rework-Process for the modell attached and I have some questions:

1. I need to send the Items from Processor 2 to the Queue by Type( Type1,2 and 3)and wait untill I have 2 boxes in every queue and then I can send it to the next operation.

2. The Cell1 and Cell2 represent the same Machine but every Cell has it own Processing time, The problem is that I can't release The Box from Cell2 untill the ende of the Processing time in Cell1.

Thank you so much

Model Kd test.fsm

Re: waiting in Queue untill the desired quantity reached

moehlmann_fe — Mon, 13 Feb 2023 11:57:42 GMT

1. Would the queues be closed for further input until the six items have moved on? Or is it more of an ongoing condition (only release if there are at least two in each)?

2. This can be done by opening/closing the output of the second cell. Close it when an item enters cell2 (On Entry trigger) and open it again when an item finishes processing on cell 1 (On Process Finish trigger)

Re: waiting in Queue untill the desired quantity reached

TalHzf — Mon, 13 Feb 2023 13:45:38 GMT

Hi @Felix Möhlmann ,

Thank you for Your answer.

1. The boxes schould be processed two by two, it means that I can only send when at least 2 boxes from the same type are in the queue.

2. I tried opening/closing the output , but It didn't work, I don't know why. I just want to mention that when the Processing time in Cell1 < Cell 2 we don't need triggers, but when the Processing time in Cell1 > Cell 2 , Cell 2 should wait untill ende of Cell1.

Thank you

Re: waiting in Queue untill the desired quantity reached

moehlmann_fe — Mon, 13 Feb 2023 14:31:52 GMT

1. Then you can just set the queues to use batching behaviour. In order to make sure that the pairs don't get mixec up, I would have the queues push them to a list. The processor can then pull them off in the correct order.

2. Another question would be if this applies always (an item can never leave cell2 without an item waiting at the end of cell1) or only pair wise (the first item in a pair has to wait for the second, but the second can continue immediately).

The difference between the two would be a condition that the output of cell2 is only closed for every second entry.

model-kd-test(1).fsm

I've build a faster scale example so the logic is quicker to observe.

Re: waiting in Queue untill the desired quantity reached

TalHzf — Mon, 13 Feb 2023 15:03:44 GMT

Hi @Felix Möhlmann ,

I think I didn't explain good my case.

I have a machine which is simulated with 2 processors, the doors of the machine open once when the biggest processing time Cell is finished.Sometimes the Cell2 is bigger than Cell 1 and in this case there is no problem, because the item in Cell1 is waiting. But when the Processing time in Cell1 is bigger than processing time in Cell2, Cell 2 should wait because the machine open its doors at one time.

I hope I coould good explain my case , Thank you so much for your help

Re: waiting in Queue untill the desired quantity reached

moehlmann_fe — Mon, 13 Feb 2023 15:23:26 GMT

Isn't that what happens when you remove the condition in the OnEntry trigger of cell2? (As I wrote, that makes the difference between waiting always and only every other item)

Items only advance when both processors are currently finished.

Re: waiting in Queue untill the desired quantity reached

TalHzf — Mon, 13 Feb 2023 15:52:07 GMT

Hi @Felix Möhlmann ,

Yes this is exactly what I want. Thank you, but I still can have the modification in my modell, I deleted the second trigger but I don't get the same result as you.

Thank you fpr your help

Re: waiting in Queue untill the desired quantity reached

moehlmann_fe — Mon, 13 Feb 2023 15:55:51 GMT

Don't delete the whole trigger. Just delete the expression in the "Condition" field (or rather replace it with either "true" or the value 1)

Re: waiting in Queue untill the desired quantity reached

TalHzf — Tue, 14 Feb 2023 09:11:28 GMT

Hi @Felix Möhlmann ,

Thank you, It works now