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Minimize function in Mathcad 1

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Mechv5

Mechanical
Joined
Jan 28, 2009
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EU
Hello everybody,

I'm trying to define a spiral spring with a characteristic as flat as possible (meaning a "k" as small as possible), but the "minimize" function of Mathcad don't want to help me... :-)
Please take a look at the attached Matchad 11 file and tell me what I'm doing wrong...

Thanks in advance!

Mechv5
 
It appears as if you need to give all of a functions input arguments when using minimize or maximize.

If you're using M11 then you can define an auxiliary specialized variant of k(b,t) that only takes b as a parameter, eg kt(b):=k(b,t), which will pick up the value of t in force at the place of definition. If you are using M12..M15 (certainly M13..M15, can't speak for M12 for sure), then you could use a local function definition to allow you to temporarily create a function within the call to minimize itself (eg, minimize(f(b)<-k(b,t),b) ... again, it will pick up the in-force value of t.

You also need to write sigma with all of it input arguments within the solve block, not just give its name.
 
 http://files.engineering.com/getfile.aspx?folder=c23f3615-7538-4c58-b1b3-0827c5f7d2b1&file=Spiralfeder_Tablefold_minimize_k.mcd
Thank you very much, excognito, it looks like it works the way you described! I will play with it a little bit, to see if I can get some realistic results :-).
 
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