topic Re: Optimization in Robot Structural Analysis Forum

Optimization

Anonymous — Thu, 28 May 2015 08:53:19 GMT

Helo,

Here I am going to use option Optimization? Is it possible here, that Autodesk RSA will tell me for any member in the structure -

1)this member in the structure has lowest utilizatuion ratio and you can remove it. such that it will save my material cost. or

2)you can use the material with lower strength than current one or

3)you can reduce the cross section of this member?

Re: Optimization

Rafal.Gaweda — Thu, 28 May 2015 10:02:22 GMT

3 x yes

BTW see the 3rd webinar:

http://forums.autodesk.com/t5/robot-structural-analysis/robot-structural-analysis-webinars/td-p/5523337

Re: Optimization

Anonymous — Fri, 29 May 2015 07:46:22 GMT

Helo..

I hd gone thru ur webinar. it says me to replace the current member section by any new one to reduce the utilization ratio.

it doesnt help me for any of the above questions..

It doesnt tell me that any part is having lowest utilization and it can be removed

it doesnt help me tofind substitute material for any member having extra strength than needed.

Re: Optimization

Rafal.Gaweda — Fri, 29 May 2015 07:51:58 GMT

No, the program is not that smart.
Programs gives you ratio results and you have to decide whether to remove element from structure or change section or change material

Of course it can be done in automatic way if you program your own "Optimization" procedure doing that using Robot API

Re: Optimization

Anonymous — Fri, 29 May 2015 08:17:53 GMT

robot API??? WHAT IT IS? is it the option in Robot? or any other software tool? how to use it?

Re: Optimization

Rafal.Gaweda — Fri, 29 May 2015 08:23:17 GMT

http://en.wikipedia.org/wiki/Application_programming_interface

Re: Optimization

Anonymous — Fri, 29 May 2015 08:30:15 GMT

Can u provide me API tutorial for ROBOT?

Re: Optimization

Anonymous — Fri, 29 May 2015 09:00:37 GMT

ok.. 1 more question, in optimization option, there is option to select WEIGHT, what is it? is it doing optimization for weight? i.e. keeping strength constant while reducing weight? What affects if i select that Weight option and if I dont select that weight option? Does it Realy affect the calculation?

Re: Optimization

Rafal.Gaweda — Fri, 29 May 2015 09:03:41 GMT

http://forums.autodesk.com/t5/robot-structural-analysis/api-tutorial/td-p/3939601

http://forums.autodesk.com/t5/robot-structural-analysis/api-macro-with-robot/m-p/5639501#M33941

Re: Optimization

Rafal.Gaweda — Fri, 29 May 2015 09:09:34 GMT

Re: Optimization

Anonymous — Fri, 29 May 2015 12:41:19 GMT

sorry.. bt i dont understand the use of weight option? Kindly guide me

Re: Optimization

Artur.Kosakowski — Fri, 29 May 2015 12:47:25 GMT

The choice of a best section is for a lightest section that has got its design ratio below 1 rather than the one that has the ratio closest to one (e.g. 0.99).

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

Re: Optimization

Anonymous — Mon, 01 Jun 2015 06:51:34 GMT

You mean, if i have three sections,

1. utilizatuion ratio = 0.8 and weight = 5T

2. utilization ratio = 0.7 and weight = 6T

3. utilization = 1.1 and weight = 4T

If i select weight option, Robot will suggest me to use First section as it is having minimum weight and utilization below 1

if i dont select weight option, Robot will suggest me to use Second section as it is having minimum utilization

robot will never suggest me to use third section, whether I select weight option or not as it is having utilization ratio above 1...

Right???

Re: Optimization

Artur.Kosakowski — Mon, 01 Jun 2015 07:27:53 GMT

If i select weight option, Robot will suggest me to use First section as it is having minimum weight and utilization below 1

Correct

if i dont select weight option, Robot will suggest me to use Second section as it is having minimum utilization

Wrong. It will pick up the 2nd as 0.8 is closed to 1 than 0.7 but it would select 0.9 and 12 T.

robot will never suggest me to use third section, whether I select weight option or not as it is having utilization ratio above 1...

Correct.

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

Re: Optimization

Anonymous — Mon, 01 Jun 2015 08:50:35 GMT

Here, our intention is to minimize the utilization... right? then if one section with lesser utilization is available (0.7 and 6T), why it is providing me 0.9 and 12T

what is our xact aim? to keep utilization as minimum as possible or to keep utilization near one?

And if it is saying me to use 0.9 and 12 T, then it would be wrong optimization as it is incresing my utilization and it is also increasing my weight..

How can we justify this?

Re: Optimization

Artur.Kosakowski — Mon, 01 Jun 2015 09:24:46 GMT

then if one section with lesser utilization is available (0.7 and 6T), why it is providing me 0.9 and 12T

Because you target is the ratio rather than weight. In most of the situations for European section databases the result will be the same as for the family of sections the weight corresponds directly with the strength.

what is our xact aim? to keep utilization as minimum as possible or to keep utilization near one?

The latter. For the prior you can change the value of the ratio limit (e.g. set it as 0.7 instead of 1). Otherwise just select the largest section available

And if it is saying me to use 0.9 and 12 T, then it would be wrong optimization as it is incresing my utilization and it is also increasing my weight.

Again if you want additional safety margin reduce the ratio limit. If you want the lightest possible section mark this option as the criteria for the group design.

Re: Optimization

Anonymous — Mon, 01 Jun 2015 11:19:27 GMT

how to set the ratio limit? 0.7 instead of 1?

Re: Optimization

Artur.Kosakowski — Mon, 01 Jun 2015 11:24:34 GMT

Configuration > efficiency ratio.

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

Re: Optimization

Anonymous — Thu, 04 Jun 2015 04:54:02 GMT

can we add newly defined sections to the sections list while creating groups for optimization purpose. i hv tried bt it doesnt show me any of the section created. it shows me only one section - Test 4*8*0.5, what is this section? i never defined such kind of section

Re: Optimization

Artur.Kosakowski — Thu, 04 Jun 2015 21:49:51 GMT

You need to save them in the user section database making sure they have the same family name e.g. :

A 100

A 200

A 300

etc.

The section you can see is just the predefined "test" one so that the user section database is not empty.

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.