How to assign each transporter to be in charge of different queues?

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Yifei Wang asked Jun 28 2016 at 1:10 PM Brandon Peterson commented Jun 28 2016 at 7:43 PM

How to assign each transporter to be in charge of different queues?

Hi,

Please see my model. Based on this model, I would like each transporter to be in charge of multiple queues. For example, I would like the transporter 1 to be in charge of moving all desired objects from racks to queue 1and 2. Transporter 2 is going to be in charge of moving all desired objects from racks to queue 3 and 4. Can someone help me with this? Thanks!

Note: one queue may need multiple kinds of itemtypes. Please refer to the model.

newmodel.fsm

Software Version:

FlexSim 16.1.0

queues forklift

newmodel.fsm (28.4 KiB)

Answer 1 · 2016-06-28T13:54:39Z

Brandon Peterson answered Jun 28 2016 at 1:54 PM Brandon Peterson commented Jun 28 2016 at 7:43 PM

Yifei,

On the racks in your model you can use the "Center Port By Case" picklist option in the Use Transport field. In the field "Case Function" enter the word "port". Then you can set the cases 1 and 2 to return the number for the center port connection to transporter 1 and the cases 3 and 4 to return the number for the center port connection to transporter 2. Doing it this way will not be affected by the itemtype of the flowitems.

Hope this helps!

Brandon

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Yifei Wang commented · Jun 28 2016 at 2:06 PM

Brandon,

Thank you for your reply. I set up the model in the way you described. However, transporter 1 works does not goes to queue 2 instead it goes to queue 3. Transporter 2 is not moving at all. Do you know why this happens? newmodel.fsm

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newmodel.fsm (28.9 KiB)

Yifei Wang Yifei Wang commented · Jun 28 2016 at 2:31 PM

Brandon,

Please see the new attached model. I fixed some code in the previous one. But, I am still not sure why Center Port by Case is not working here.

newmodel.fsm

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newmodel.fsm (28.9 KiB)

Brandon Peterson ♦ Yifei Wang commented · Jun 28 2016 at 7:26 PM

Yifei,

Because you are using the option to pull from a list for your send to port field the port value returned to the use transport trigger is 0. This is why it does not work for you.

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Answer 2 · 2016-06-28T16:50:45Z

Adrian Haws answered Jun 28 2016 at 4:50 PM Yifei Wang commented Jun 28 2016 at 7:38 PM

Hi Yifei,

We were able to find another solution using the Send to Port in rack properties with "Push to Task Sequence List" instead of "Center Port By Case." Then in that list add another Expression Field called "unloadStation." So each of these racks will send the destination of the object to a list. Then in each transporter in the OnResourceAvailable trigger click on "Pull from Task Sequence List" and enter a Query to determine which partitions to pull from. So for Transporter1 it would look like this:

WHERE unloadStation = node("/Queue1", model()) OR unloadStation = node("/Queue2", model())

We ran the model and it seemed to work just fine according to what you described. See attached model and let us know if you have any questions!

1001-newmodel-1.fsm (29.9 KiB)

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Yifei Wang commented · Jun 28 2016 at 5:05 PM

Hi Adrian,

Thanks for your answer. I am glad it works!! I am wondering how to fix my SendToPort on Racks because I would like the transporter to send the items to the shortest queue among the ones it is responsible for.

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Yifei Wang commented · Jun 28 2016 at 5:06 PM

1010-1001-newmodel-1.fsm

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1010-1001-newmodel-1.fsm (29.8 KiB)

Adrian Haws Yifei Wang commented · Jun 28 2016 at 5:30 PM

@Yifei Wang it looks like your model is already doing that in the Query for

ORDER BY queueSize ASC

When you step through your model and look at the entries for FRList1 it shows that each item does get transported to the shortest queue among those available.

Does the updated model do what you want it to?

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Yifei Wang Adrian Haws commented · Jun 28 2016 at 7:38 PM

Adrian,

When you look at the model when it runs, the transporter does not always go to the shorter queue.

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Answer 3 · 2016-06-28T13:53:19Z

David Besson answered Jun 28 2016 at 1:53 PM Yifei Wang commented Jun 28 2016 at 2:46 PM

You could:

for each Queue: add a Dispatcher and connect it with a center port
for each Dispatcher: connect the corresponding Transporters
for each Rack: change the transport field as follow: "centerobject(destination, 1)"

See attached model.

990-newmodel-r1.fsm

990-newmodel-r1.fsm (30.2 KiB)

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