Job Sequence Logic with Advanced AGV and Global List

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chia725 asked Jul 6, '23 Felix Möhlmann answered Jul 6, '23

Job Sequence Logic with Advanced AGV and Global List

Hello, I am building a model with advanced agv and back order list as job sequence. But I am wondering how does the job sequence setting interact with each others. My global list job sequence is as follow:

Queue (push to)-> ItemReadyForDelivery -> Processor(pull from)

Processor (push to) -> ItemReadyForSink ->Sink (pull from)

I use the query " ORDER BY RAND() " so as to make the agvs reached the processors randomly.

I am wondering how does the next work point branches work with the global list. Does the agv follow the global list sequence first or follow the path choosing of the next work point branches? The attached file is my model, thank you so much for your help!

model: random.fsm

Software Version:

FlexSim 21.2.4

task sequence global list advanced agv

1688614557661.jpg (127.3 KiB)

random.fsm (179.2 KiB)

Answer 1 · 2023-07-06T07:11:06Z

Felix Möhlmann answered Jul 6, '23

As soon as a processor or the sink pull an item from one of the lists, the Use Transport reference field of the object in which in the item currently sits is evaluated. This pushes the item onto the AGVWork list. The AGV Process Flow is now 'aware' that there is an item to be transported.

The AGVs 'patrol' the network along the NextWorkPoint loop. If they arrive at a control point they check if there is an item to be loaded there (if they still have capacity) or if an item that they have currently loaded should be unloaded there. The Process Flow will never directly send an AGV to pick up an item. Pickups only happen when the AGV passes the position while moving around the NextWorkPoint loop. So if any control point does not have an incoming NextWorkPoint connection, no item will ever be loaded from the connected location!

This is similar for unloading items. An AGV has to move by the unload location 'by chance'. The only exception is if the AGV has reached its maximum load capacity. In that case it will directly move to the unload destinations until it is empty. (Unless you change the Process Flow Variable UnloadToEmpty to 0, in which case the AGV would only unload one item and then continue to move along the NextWorkPoint loop).

So in essence, the order in which items are pushed to the AGVWork list only has an impact when there is more than item waiting at a station.

Please see the manual for more details about the AGV template.

https://docs.flexsim.com/en/21.2/WorkingWithTasks/AGVNetworks/UsingAGVProcessFlowTemplate/UsingAGVProcessFlowTemplate.html#behavior

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