question

Rahul R avatar image
0 Likes"
Rahul R asked Jeanette F commented

Operators blocked even when the conveyor entry transfer is not blocked

I find the operator trying to unload a flow item onto an entry transfer blocked even though conveyor has space. I tried making the entry transfer wide to span over two dog positions. I have checked the option to block transporter if space is blocked to block operator if there is no space on the conveyor. I have attached the model.Test_Model.fsm


1699599677285.png

FlexSim 23.2.2
conveyorstransportersentrytransferdog interval
1699599677285.png (587.9 KiB)
test-model.fsm (2.2 MiB)
· 1
5 |100000

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

Jason Lightfoot avatar image Jason Lightfoot ♦ commented ·
It looks like only the center point of the entry transfer is used to assess the availability of a dog.
0 Likes 0 ·
Felix Möhlmann avatar image
0 Likes"
Felix Möhlmann answered Jeanette F commented

I also assume that an item can only enter a conveyor at the center of the Entry Transfer. To allow a continuous entry, you would need to somehow keep track of empty dog positions, so you can move the transfer to the correct location.

While it should theoretically be possible to do this entirely virtually (as long as the conveyor never stops each dog position can be calculated based on the current time) a simpler way might be to introduce carrier items onto the belt. Each dog position is taken up by a carrier. You can then push available carriers within a certain of the conveyor onto a list and have the items/operator pull the next available one.

carrier-belt-example-fm.fsm

· 2
5 |100000

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

Rahul R avatar image Rahul R commented ·

@Felix Möhlmann : This makes sense. Thank you! The ability to track empty carriers between two points is what I was looking for. Do you think it may be useful to have ability to listen to event for a dog passing a decision point and also knowing if there is anything occupying the dog in future FlexSim releases? Also, please feel free to convert your reply to the answer.

0 Likes 0 ·
Jeanette F avatar image Jeanette F ♦♦ Rahul R commented ·

Hello @Rahul R,

You can add that as an idea so the developers know it is a current feature request and other users can vote on it.

1699999568587.png

1 Like 1 ·
1699999568587.png (25.1 KiB)
Kavika F avatar image
0 Likes"
Kavika F answered Kavika F commented

Hey @Rahul R, I think there are gaps because you have your Operators use a "Load Time" currently set to a parameter. That parameter is set to ~3.6 seconds. The dogs come faster than the Operator can put on.

· 2
5 |100000

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

Rahul R avatar image Rahul R commented ·
Shouldn't the operator be in "Loading state" if the dogs are coming faster than the operator. Visually it does seem like they need the dog to align with center of the entry transfer and width of the entry transfer covering multiple dog positions does not seem to matter. The intention of the modeling here to simulate associate loading a cross belt. The associate could load a part to a cell that is slightly ahead or trailing.
0 Likes 0 ·
Felix Möhlmann avatar image Felix Möhlmann Rahul R commented ·

I also assume that an item can only enter a conveyor at the center of the Entry Transfer. To allow a continuous entry, you would need to somehow keep track of empty dog positions, so you can move the transfer to the correct location.

While it should theoretically be possible to do this entirely virtually (as long as the conveyor never stops each dog position can be calculated based on the current time) a simpler way might be to introduce carrier items onto the belt. Each dog position is taken up by a carrier. You can then push available carriers within a certain of the conveyor onto a list and have the items/operator pull the next available one.

carrier-belt-example-fm.fsm

3 Likes 3 ·