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Structural optimization matlab, need some advices how to start

Structural optimization matlab, need some advices how to start

RE: Structural optimization matlab, need some advices how to start

I'd recommend a monte carlo



bestscore= 1e9
bestdesign=initial state of N members

for runs=1:100000

for modmember =1:N
newdesign=bestdesign with randomly modified property for member modmember (consider what step size to use)
end
newscore=score( newdesign)
if newscore<bestscore
bestscore=newscore
bestdesign=newdesign
end
end

Designing score is the hardest part in the real world, luckily they've done most of that for you.

There are more elegant methods, but monte carlo is robust and easy. CPU time is cheap, let the computer try a million pointless experiments overnight.




Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

RE: Structural optimization matlab, need some advices how to start

not monte carlo.
use a book.

RE: Structural optimization matlab, need some advices how to start

This should reduce the number of runs

initially set the size of each member so that its stress is just less than one specified. I very much doubt the deflections will significantly alter the bar forces, so that is a minium size.

then

repeatt

estimate the sensitivity of the maximum deflection to a small change in each bar size

use that sensitivity analysis to bring that max deflection down to the target value, efficiently, by increasing the bar sizes.

until no node mcves more than it should

So, now you probably have an overweight but rational structure. Then use the monte carlo.





Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

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