Model gets blocked with Conveyor but not with que?

[moosa]

[ FlexSim 22.2.2 ]

[jason_lightfootVL7B4]

Can you post your model for us to take a look?

[moosa]

model_built_mockup_testing_final_macro_1_autosave.fsm

[jason_lightfootVL7B4]

Can you post the model with which you have the issue?

[moosa]

model_built_mockup_testing_final_macro_3.fsm

[jason_lightfootVL7B4 · Accepted solution]

The reason is that the conveyor only presents the item at the end of the conveyor to the pulling queues, whereas a queue allows any of its contained items to enter any queue at the same time.

So when an item of type 37444 arrives at the end of the conveyor it does not match any of the queue Types. Later the batch timeout occurs at 13120 secs and queue293 releases its type 37537 items. At that point you need to adjust your pull logic to allow it to take a new type and have it fire by opening the input of the queue (even though it is open already - telling it to open will reevaluate the pull).

[moosa]

well i do understand what you mean,but why is that i will have to adjust the pull logic? as you could see the pull logic says whenever the sorting lane is empty,anything could enter the lane,only when it gets filled up by 1 pc then the piece belonging to that item type should enter and moreover you could see that the exit transfer of the converyor has the logic of sending output to anyone.what is that I will have to adjust in the model to solve the problem.Please note I am considering the subnodes.length property.

[jason_lightfootVL7B4]

When I chose to trigger the pull re-evaluation your logic did not allow the item to enter since it was triggered by the last item leaving which is a usual technique. Your code tests for the content being <1 which will never be the case as the pull is evaluated while the exiting item is still in the queue.

[moosa]

ok so what should I do to solve the problem, here the input from the que could enter into any of the available lanes(18 lanes),once an item enters, the lane takes its value and is reserved for that particular item until it reaches the quantity as 5,once it reaches the quantity as 5 and is send to the machine if machine is not occupied ,the lane takes the value of 6th item entering and is reserved for that type until it reaches the max limit of the lane which is 10.

[jason_lightfootVL7B4]

Instead of altering the pull it will be simpler to schedule an event to open the queue input if it is empty (on exit trigger):

if (current.subnodes.length==1)
     createevent(current,0,EVENT_USEROPENINPUT);

Model attached.

model-built-mockup-testing-final-macro-3_jl.fsm

[moosa]

well if I change the content to 1 my whole logic of wanting to obtain the item label value on the object fails.what I dont understand is I am using the subnode.value property which is solely dependent on the object,why is it interfering with the with input logic.Could you help me out in solving this out, it would be helpful.

[jason_lightfootVL7B4]

Yes, sorry I realised the problem and edited the reply - see above.

[moosa]

I have tried adding that trigger to the lanes, but it doesnt take any items from the conveyor,Please note if the subnode.value ==1 then that particular lane is reserved for a particular type of item.

[jason_lightfootVL7B4]

I used your original pull and added the trigger to the exit in the model attached above and it works fine.

[moosa]

could you please share the model on which you have made changes, it would be helpful.Thanking You in advance.

[jason_lightfootVL7B4]

It should be 5 posts up but here it is:

model-built-mockup-testing-final-macro-3_jl.fsm

[moosa]

thanks a lot for this solution, really appreciable, but I still have issues regarding the duplication of lanes, how do I solve it ? I did some modifications in pull and push logics as shared in the model,Could you help me out in solving the issue of duplication.

duplication_lanes.fsm

[jason_lightfootVL7B4]

Are these really conveyors - all the lanes and the feeder - and if so why are you modelling them as queues?

[moosa]

well i am modelling them as queue as it could be a que or conveyor or both ( each of these lanes have input logic,which i believe would be better implemented by que rather than conveyor, but the output logic is the same first come first out,even if i replace que with the conveyor the output yielded would be the same and queue provides me with additional aspects of dwell time or max stay time, In any case how could i avoid duplication of lanes at input perspective,like at one instant of time I am having 2 lanes of same type ,but instead I want to have only 1 lane at same time . why is that you are asking me to model it as conveyor does conveyor has better inpout logic to the queue ?

[jason_lightfootVL7B4]

It was more to avoid building the logic twice - once for the queues and then again for the conveyors if that proved to be the ultimate goal. Let's answer your question in the other thread as the question about conveyor vs. queue is answered in this one.