I have a little problem with my model
I'm using two stores, the parts are stored when some buffer or machines have failed. Then, when a part enters to any machine an attribute is created to move the part from the store to the correct machine when is operational again.
The problem is it appears a message with the next error: User-defined attribute was not found, I can't identify what is the problem because the attribute is created in the entrance of OP20.
I hope you canl help me, or give some suggestions for modeling this process easier.
I have attached my model
Solved! Go to Solution.
the part P1 already has the attribute 'Next_OP40'.
Please keep in mind, the front oriented exit control can be activated several times. I assume in your model the MU alrready wants to exit station OP30B, but cannot move to the successor. Therefore the MU will be entered in the backward blocking list of the successor and as soon as the successor is empty, the MU will be moved and the exit control will be executed for a second time.
so you should chnage your exit control in a way like:
if OP40.empty and OP40.Operational and L3.empty var target : object := L3 elseif L3.full target := Store if L3.full and Store.full target := Store_2 end else target := L3 end if @.move(target) then -- this will be executed only if the product can be moved switch @.name case "P1" @.DeleteAttr("Next_OP30") @.createAttr("Next_OP40","string") end
very often you create an attribute and delete the attribute again without assignng a value to the attribute.
Creating and deleting attributes is a time consuming operation. i would recommend to create an attribute 'Next_Operation' of type string and assign the next operation to this attribute:
@.createAttr("Next_Operation","string") @.Next_Operation := "OP30"
Hope this helps.
Thank you so much for your help
I applied the modifications that you suggesting me and the creation and the assignment of a value to the attribute, it works very well, but I found another problem:
some parts stored don't move to his its respective buffer and when the new part type is going to enter the parts are mixed and the setup time is applied again. In the real process, the new part can't move to the operations until the last batch have been released. I created other buffers (BA11, BA12, and BA13) to move parts in case there is not enough capacity
I hope you can help me