How to group transporters (or task executors)?

[lincoln_sellers]

[ FlexSim 7.5.4 ]

I have 3 unload positions (or lines) where 4 transporters go to get unloaded. How can I sequence transporters so that as soon as all the transporters at a particular position are done, more transporters (4) are dispatched to the position in the right order (front position, then next, then next, etc.).?

I have been able to keep the transporters there while being unloaded, but the model is not wanting to give me a true round robin on the flow (or dispatch), which is what I want. I have tried setting labels and itemtypes to sendto port but cannot get it to function properly. How can I solve this problem and move on with my model?

[adrian_haws]

@Lincoln Sellers It would be helpful for us if you could send a sample model, since it's hard to tell exactly what you're trying to do just from the description. Thank you.

[lincoln_sellers]

sequence-2.fsm@Adrian Haws Of course I can, and I meant to on the first question. This is a smaller model and only has two "lines" of processors, but I will eventually have three. I am trying to get the task executors to flow in order of port number from the exiting queue.

Also, how can I do this with more tugs than exit ports? (for example, if I had a parking lot full of task executors that I wanted to call on when needed, while sending the used task executors back to the lot)

[sam_stubbsYXX86]

Do you have access to a newer version of FlexSim than 7.5.4? There has been quite a bit of functionality added (namely Process Flow and Lists) Two tools which would greatly simplify this problem.

[lincoln_sellers]

No, I do not have access to anything but 7.5.4

[sam_stubbsYXX86 · Accepted solution]

You can take a look at this example model I updated. In order to achieve the effect of having them dispatch as a group and move as a group, I used batching on the Queues (essentially making it so that the queue will only let three (the number of executers per line) out at a time to retrieve the item.) Then I had the processors send a message to the on the OnExit trigger. and then had the queue increment a label when the OnMessage trigger fired. And allowing more items through when that label increments to a certain value.

This process keeps the lines moving together as a group. There is still the issue that occasionally they will not deposit the items all in sequence as a group (the first one arrives to the first spot instead of the last) But they will stay on the line as a group until all the executers in their line have finished unloading. The sequencing has to do with when the processor finishes processing the item, allowing another item available to be pushed. So the task executers will retrieve the item in the order that they are "pushed" into the queue. You could try playing around with this using messages or other triggers or code to try and force them to drop items off in specific sequence.

1475-sequence-2.fsm

Again if you can, I would strongly encourage you to obtain an updated version of FlexSim as you will find the more recent tools and features could greatly help. Especially in this particular area.