MATLAB: Time and event based data into ressource pool

eventresourceSimEventssimulinktime

Hello everyone,

I have a model with both time and event based aspects. In a time based simulation, a recycling facility is modeled that continuosly takes in material and outputs amongst others) a recycled target material. In the event based part of the model, a manufacturing facility is simulated: Orders arrive and are processed, consuming the material provided by the recycling facility.

I get both parts to work fine, the only problem is: I want the Ressource Pool the manufacturing draws from to be fed by the recycling. To do that, I have to claim that the ressource is "Reusable upon release", so I set the "Resource amount source" to Signal port. Using a "Time to Event Signal" block, this works well, the Ressource pool will hold the material recycled in the recycling line. But as material for production is obviously not reusable, I tried to manually substract the used material: The entities that represent the manufactured products have a "size" attribute. I was trying to add those up using "Sum of Elements", and was playing around with other approaches, but none worked.

Any ideas on how to solve that? Thanks a lot!

Best Answer

For anyone who stumbled upon this, the answer is simple enough - use the #d port of the Resource acquire block, which tracks the number of finished products, time the material attribute, thus calculating the total matial used. Substract from the total recylced material.

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Hi Kar,

The testEntry method is invoked before an entity enters a storage. This method allows to either accept or refuse an entity from entering that particular storage. In the case of the storage for Task entities, the callback method name would be TaskTestEntry and for the Failure storage it would be FailureTestEntry.

For this example, when a Failure entity arrives into storage 2, an internal flag can be set in the block that would block Task entities from entering the block. When we are done processing the Failure entity, we can reset the flag so that we can start accepting entities into Storage 1. To check if any entities are waiting to enter storage 1, we can schedule a testEntry event for storage 1.

Regards,

Krishna

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Hi Kar,

You are correct, Entity Server does not allow for changing the capacity at run-time. Resource Pool block allows changing the resource amount at run-time through a signal port, but it only allows incrementing the available resources in the pool. And not the other way around.

For the variable capacity server, you can try using a MATLAB discrete-event system block and try including a queue of infinite capacity. You can then control whether to allow or disallow an entity from entering the queue by implementing the testEntry method. That way you can control the capacity at run-time. For example you can do something like the following:

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Hope this helps!

- Krishna

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