Dinamically disable or enable a process flow source

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Manuel Álvarez-Requejo asked Sep 5, '23 Jason Lightfoot edited Sep 5, '23

Dinamically disable or enable a process flow source

Hi there!

I have got a model simulating a factory that works in shifts. When there is a change in shift, there may be a need for a format change on the machine.

The machine generates boxes at a certain speed depending on the format that it is working on, so I am using in process flow an inter-arrival source for this.

The problem is that when there is a format change, I would like to disable the source as long as the format change is happening and reenable it when the format change is done, having the timer for the generation of tokens reset.

I am attaching a simplified version of my model that I think may be representative.

In this versions, shifts last only 1 hour, and there are 2 formats that take 500 and 700 seconds to produce, with a format chang time of 30 seconds. As you can see, after the shift change, the next product is delivered at 4000 seconds (500 seconds after producing the last object during the first shift). What should happen is that the product is made at 4330 seconds (30 seconds of format change and 700 seconds to make the first product AFTER THE SHIFT CHANGE).

questionflexsim.fsm

Could anyone tell me if it is possible to disable and reset the timer in the inter-arrival source?

Or if you could find a simpler solution, I would be really thankful :).

Thank you in advance,

Manuel

Software Version:

FlexSim 23.1.2

source manufacturing process dinamically disable

questionflexsim.fsm (33.9 KiB)

Answer 1 · 2023-09-05T11:25:06Z

Jason Lightfoot answered Sep 5, '23 Jason Lightfoot edited Sep 5, '23

You're not really modelling the process and setup time with this - you have a decoupled interrupt that could come and go without the main process being affected.

Attached is an alternative that still uses most of your method, but doesn't rely on a source interarrival time - instead it models the machine's process.

Note that the machine has started processing 500 seconds of an item when the first shift change occurs so it finishes that and THEN invokes the change so that the next item is produced at 4730.

questionflexsim_jl.fsm

questionflexsim-jl.fsm (34.4 KiB)

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