question

Allister Wilson avatar image
2 Likes"
Allister Wilson asked Bo.W commented

Exception when resuming an AGV which was stopped during offset travel

One of our customers added a MTBF/MTTR to their AGV model and found an issue with the new offset travel functionality.

It seems that stopping an AGV (with stopobject) at any point during an offset travel operation causes an exception to be thrown within resumeobject when you later try to resume it.

The attached model demonstrates this issue 14 seconds into the run.

For now I've got the customer's model running again by handling the offsets manually (as normal travel operations) in process flow, but I'd love a simpler workaround if you happen to find one.

20200526_agv_offset_with_stop.fsm

FlexSim 20.1.2
flexsim 20.1.2agv networkoffset travelresumeobject
20200526-agv-offset-with-stop.fsm (31.1 KiB)
· 2
5 |100000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 12 attachments (including images) can be used with a maximum of 23.8 MiB each and 47.7 MiB total.

Allister Wilson avatar image Allister Wilson commented ·

Has anyone had a chance to look into this?

0 Likes 0 ·
tannerp avatar image tannerp commented ·

@Allister Wilson I believe this might involve a bug. I'm not sure who is looking into it that could give you more information. I think the bug is related to this post, but I could be wrong.

0 Likes 0 ·

2 Answers

Phil BoBo avatar image
0 Likes"
Phil BoBo answered Bo.W commented

Yeah, this looks like a bug. I'll add a case to the dev list.

We seem to have overlooked this question.

· 3
5 |100000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 12 attachments (including images) can be used with a maximum of 23.8 MiB each and 47.7 MiB total.

Bo.W avatar image Bo.W commented ·

Has the bug been fixed yet?

0 Likes 0 ·
Jason Lightfoot avatar image Jason Lightfoot ♦♦ Bo.W commented ·
Yes this is resolved in 22.0.6 and 22.2.0
0 Likes 0 ·
Bo.W avatar image Bo.W Jason Lightfoot ♦♦ commented ·
OK,Thanks.
0 Likes 0 ·
gilbert jerald avatar image
0 Likes"
gilbert jerald answered Allister Wilson edited

@ allister.wilson You have used pickup point connection in you model that is not been referred anywhere that cause error in you model when AGV reach the pickup point. Normally the Pickup point connection are used when your model has more than one pickup point option. When you used the connection you should commend the AGV by process flow or by network properties to look for the available pickup point.

I have attached the modified model for your reference have a look at it

Support AGV.fsm


support-agv.fsm (31.2 KiB)
· 1
5 |100000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 12 attachments (including images) can be used with a maximum of 23.8 MiB each and 47.7 MiB total.

Allister Wilson avatar image Allister Wilson commented ·

Thank you for taking a look, unfortunately this just sidesteps the problem.

The pickup point connection is used within the On AGV Offset Travel trigger.
There is only one here for simplicity, but in a real model you'd have many pickup points (or some other connection type) to make use of the new AGV offset functionality.

In your model without the pickup point connection, no offset travel occurs, therefore the problem outlined in my question does not occur either.

For reference, having unused control point connections will not break your model.
As far as I know, connections other than Location (including the connection types added by default) have no inherent behaviour and will only have an effect if your logic (ex: the built-in AGV process flow template) uses them.

1 Like 1 ·