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Problems with GA

Experimenter
Experimenter

Hello,

 

I want to try to improve a production sequence. I want to use a GA for the improvement.

I do not know how to apply the GA with the GAWizzard.

 

I have added a simple example of what i want to create.

 

Could somebody tell or show me how i can get the GA working.

 

I have some initial sequences in a table.

I have a table with the assembly time per product per station.

I have a method to calculate the overtime (i want to minimize the overtime)

 

The idea is to find a new better sequence (less overtime)

3 REPLIES 3
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Re: Problems with GA

Siemens Phenom Siemens Phenom
Siemens Phenom

Hello CODK89,

 

you used the method for the calculation of the fitness.

The result was not correctly inserted.

Since your optimization is only a calculation, I added an Init method.

Please note that your optimization problem is very large such that will not obtain the global optimum.

GA_90.jpg

The model is for version 9.0.

Regards,

Peter

Re: Problems with GA

Experimenter
Experimenter

Thanks for your help Peter,

 

I am aware that i am not able to find the optimum solution. But i want to see if i can find a "good" solution, with the method. I compare this with other sequence methods.

 

How did you changed the insertion of the result?

Did you changed other things ?

 

Thanks in advance,

 

Chris

Re: Problems with GA

Siemens Phenom Siemens Phenom
Siemens Phenom

Hello Chris,

 

the evaluation of an individual is done by a simulation run.

Therefore I inserted an Init method with the call of your method:

     Calculate_Overtime;

I detected that your method changes the first cell of the tablefile Score_OVertime.

In the method for the Fitness calculation I used the instruction (Button Edit of the first tab Define of the GAwizard):

     result := .models.frame.Score_Overtime[1,1];

Is that value the evaluation (Fitness) of the sequence? I did not check it.

I had changed only these 2 things.

You had correctly registered the tablefile InitialSequences, the sequence of which is optimized. During the optimization you can see how the GAwizard changes its sequence.

 

Regards,

Peter