qustions about building loop agv model

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Jungeun W asked Feb 8, '23 Matthew Gillespie commented Feb 20, '23

qustions about building loop agv model

agvloop+logic.fsmHi! I want to ask several quenstions about loop type agv model.

I set 4 agvs in the loop, and there are 2 charging spots for agv.

1. as running time becomes longer, 2 agvs stays still in the charging spots and other 2 agvs travels the loop without picking up/down the flowitems. why they act like that? how to fix it? I want to make all 4 agvs work infinitely before stop running the model, and battery be charged when the battery level is below 30.

2. in the rack->conveyor transfer in the model, I set the same entry orientation for every 5 entry transfer: Forward: y+, Up: z+. But only entry transfer work- as SC pickup item and move it on the ocnveyor, flowitem locate on the conveyor. How to let other 4 entry transfers behave same as the 1st one?

3. I want to see whether the AGV is pickup the right flowitem or not- I set the straight FIFO logic of loading item while agv is searching for work. I set several workpoints- each workpoint connects with several workforwarding points. What i want to do is that if agv reach the workpoint after finishing unloading flowitem, agv serching for work(loading items) in the list of connected workforward points(applying FIFO in the list of workforwarding points).

really sorry for my poor english,,, Im not sure it is understandable or not...

plz help, thx!

Software Version:

FlexSim 21.1.5

agv battery charge loopagv

agvlooplogic.fsm (377.7 KiB)

· 1

Andrew O commented · Feb 13, 2023 at 06:32 PM

Hi @Jungeun W, was Felix Möhlmann's answer helpful? If so, please click the "Accept" button at the bottom of their answer. Or if you still have questions, add a comment and we'll continue the conversation.

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Answer 1 · 2023-02-08T08:00:06Z

Felix Möhlmann answered Feb 8, '23 Matthew Gillespie commented Feb 20, '23

1. The "Advanced" template you are using only "activates" as many AGVs as there are tasks available. For example, if there are only two pending transport tasks while all four AGVs are travelling, the first two that arrive at a control point that is connected to a parking spot without previously pulling a task, will be send to those parking points until more tasks become available again.

In your model, fewer tasks are generated concurrently than might be possible. An entry transfer will, by default, only accept a single incoming item at a time. This means, if two or more items are send to the same conveyor, only one task will be generated at a time. You can increase the "Max Transports In" setting on the Entry Transfers to allow multiple concurrent transport tasks to the same destination conveyor.

You can also completely deactivate the parking behaviour by editing the "Should I Park" Decide activity to only include the first condition that deals with charging. (So once an AGV is active it will only stop when it needs to charge. It might still take some time until all AGVs start travelling.)

2. As far as I could see all pallets enter the output conveyors in the specified orientation (y-axis in the direction of the conveyor). Do you have an example/time stamp where this is not the case?

3. The dispatcher you added to the model doesn't do anything. The AGVs are controlled solely by the Process Flow. Which item they pick is determined by the query in the "Is There an Item to Load Here?" Pull from List activity. Since the query field is blank by default, AGVs will pick the first/oldest item on the list.

I actually noticed an error in the template. The delay time in the "Breathe" activity in the lower right corner ("Work Forwarding" section) should be set to 0, not the default distribution.

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· 2

Jason Lightfoot ♦ commented · Feb 08, 2023 at 01:49 PM

Felix, I sent the error into the devs - thanks.

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Matthew Gillespie ♦♦ Jason Lightfoot ♦ commented · Feb 20, 2023 at 05:29 PM

@Felix Möhlmann @Jason Lightfoot The non-zero Breathe activity has been fixed for 22.0.13 and 23.0.4 that will come out later this week.

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