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Problem with Simulink - If block

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PQF

Automotive
Jun 23, 2008
13
Hi everyone,

I'm a beginner with Simulink. I created a very simple model to get in touch with the If-Subsystem.
The model begins with a Constant C=1 passing through an Integrator (1/s). The function obtained through the integration logically is a Line. The line then passes through a if block with a restriction [ u > 2 ].I set two scopes. One showing me the output when u>2 the other one for every other situation. I expected results to be symmetric, but apperently they are not.
Whenever the restriction is not held the values remains at 1. Could anyone please explain me, what I could be doing wrongß ? I attached a picture with the model and outputs.
thank you in advance,
Paulo Faria
 
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The scope plots from that model are correct. So your expectations are wrong or you need a different model.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
Can't say I understand the output of those If Action Subsystems either, but if you combine their outputs with a Merge block and scope the result of that, you get what you expect.
 
I was expecting two scopes to be inverse of each other. So as LiteYear suggested if you merge this two scopes you should get a constant ( in this case 1) output.

My guess is, you need to add something to refresh the else trigger, I could be totally off!
 
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