AGV Turns without Radius?

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David Parsons asked Mar 2, '23 Andrew O commented Mar 9, '23

AGV Turns without Radius?

Hello,

I've noticed a curiosity in AGV movement on my track. At certain intersections, vehicles will "jump" 90 degrees to make a turn (e.g., from the vertical to horizontal path) even if radius exists between the two permitting a turn.

The following example occurs as the part of the first vehicle movement when my model begins to run. The vehicle backs down the vertical path shown below, then "jumps" to the horizontal path. The two are not intended to be connected, though they do pass over one another. This is common in the maps we produce for our AGVs today.

Path:

Vehicle traveling(1):

Vehicle traveling(2) (post-"jump"):

However, if I remove the "X" connection point, the vehicle suddenly understands that the two are not connected. This is confusing to me, because the "X" is not actually on the horizontal path at all. It merges the vertical path with a second branch (the concave fillet shown).

Am I misunderstanding the meaning of these "X" intersections? Should be I deleting them from my path once everything is all connected/merged to prevent behavior like this?

Thanks much for your help!

flexsim_stress_test.fsm

Software Version:

FlexSim 23.0.3

agv intersections avgpath

1677764169351.png (24.2 KiB)

1677764480129.png (58.1 KiB)

1677764531391.png (51.4 KiB)

flexsim-stress-test.fsm (515.9 KiB)

· 1

Andrew O commented · Mar 09, 2023 at 07:26 PM

Hi @David Parsons, was Kavika F'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.

If we haven't heard back from you within 3 business days we'll auto-accept an answer, but you can always unaccept and comment back to reopen your question.

0 ·

Answer 1 · 2023-03-03T18:40:46Z

Kavika F answered Mar 3, '23 David Parsons commented Mar 6, '23

Hey @David Parsons, the "X"s you see denote a connection or "transfer" between paths. If you select a path, right click it, then select Refresh Path Links > Entire Network, you'll notice the "X"s update their location to more accurately represent what they connect.

If you were to delete all the "X"s from your AGV Network, then none of your paths would be connected. However, there does seem to be a problem in your model when you want AGVs to travel a desired path without hopping paths.

I assume that you only want your AGVs to travel in the forward direction (following the blue arrows in your model, except in cases where they need to go down a red path, like the ASRS queues) - is that correct? If so, then I have a suggestion you could try.

In the AGV Network > General tab, you'll see near the bottom a "Route Cost" section. You can set a "Weight" on every path so that you can favor preferred paths with lower weights and others with higher.

For example, I modified your model so every path has a "Weight" label with a default value of 1. Then I changed the weight of the paths I'd prefer them to travel on to something smaller (like 0.1). That way in the path calculation, it favors the blue-arrowed path. So now you can keep your "X"s for connecting paths and you can have AGVs travel the right path.

flexsim-stress-test_1.fsm

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1677868554061.png (4.0 KiB)

flexsim-stress-test-1.fsm (607.3 KiB)

· 1

David Parsons commented · Mar 06, 2023 at 02:07 PM

@Kavika F thanks, this seems to be helping!

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