Structural Modelling

[sumayo]

I am looking at the best way to model a Structure with regards to the ease of editing and the finished drawing output.

One way would be to use Frame Generator for all the Columns, Beams etc, then trim etc with offset and then place Endplates, Gussets etc as Parts.

The thing is, I can't demote these into Sub-Assemblies, so I can use these Sub-Assemblies more than once, (as you would in conventional modelling). Of course, this has great advantages when it comes to modifying things like for eg the "End Plate" thickness, change one Sub-Assembly is all that would be needed, instead of going through and dong each one individually.

Has anyone had similar issues and dealt with them successfully?

[Inv_kaos]

Why don't you just build your subassemblies and then place them into the parent assembly, instead of demoting them? If all your end plates, for example, are the same part then they would all update at once.

A good method you may want to look into is muscular and skeletal modeling. You can use reference parts or derived parts to control al your parameters from one location.

Or, If these are standard assemblies that you use often then link or imbed a spread sheet, that can drive all your parameters.

I use both methods depending on the situation. I hope this helps.

Regards,
Stewart

[sumayo]

Yes I do use skeletal modelling quit a lot for a lot of stuff.

I was asking about modelling Structures, Buildings etc... and I was hoping to use the power of Frame Generator, but I think it is very lacking in what you can do with it....

[Inv_kaos]

Skeletal modeling is used with frame generator. I don't see your dilemma? FG is very powerful and will do exactly what you are asking. You can use the same skeleton for both your FG members and your custom parts, ie. end plates.

Regards
SL

[sumayo]

How do you make a sub assembly of a beam with end plates? and a Sub assembly of a Column, base plate and cleats?

I have had a good look at FG and this cannot be done, and still have a structure which can be modified using FG

[JDMather]

>I have had a good look at FG and this cannot be done, and still have a structure which can be modified using FG

Why can't you create the assembly and then place as a sub-assembly in the main assembly? For that matter, why can't you simply create a sub-assembly in an assembly?

[sumayo]

To take full advantage of FG I would want to be able to Trim the Beam to the Column, with an offset of the End Plate Thickness... Can't do that across assy's in FG

[JDMather]

Zip and attach example.

[Inv_kaos]

You wouldnt need to trim to frame if you set up your skeleton correctly. You can use the same reference sketch for both assemblies.

[sumayo]

Thanks John, I appreciate you looking at this.

I have modelled this without using FG to demonstrate what I am trying to acheive.

I left the "Frame Sketch" .ipt in the assy.

Top level assy - Desired Result.iam

[sumayo]

I think I may have a solution, using a combination of iFeatures and skeletal modelling.

It would be nice if Inventor could do what I am asking, this would make give it a very competitive Structural component.

BTW This sites spell check should recognise Inventor terms for eg iFeature....

[sumayo]

Thanks for replying.

You are right I could set up the skeleton to do this, but then I could not use some of the other edit features... seems to defeat the purpose....

I like FG for welded frames, but think it is lacking if you want to use it for bolted structural applications. I don't know if you have ever seen "Pro Steel" work? This also has limitations, it is very good for initial modelling, but it is only just "ok" for changing stuff, and from memory...? I don't think the drawing updates..

I am looking for the best way to do shop drawings of a complete Beam or Column assy. Then do an arrangement drawing calling up these Assy's, all with automatic BOM's

Thanks again, I think I may have found a way to doing this using iFeatures and Skeletal modelling, maybe iAssembly's

[leem]

Sumayo
I also have been trying to use FG in this way.
Please share with us your work flow if your successful.

Many thanks
Lee

[sumayo]

Very early stages...

I have attached a zip containing an Assembly called "Structure 1.iam"
when you open it you will see it comprises 2 sub assy's called "Beam
1.iam" and "Column 1.iam" the parts in these assemblies are driven by
the paramaters in "Test Frame.ipt" as well as a bit of cross
referencing between part Parameters by way of "Derived Parts"

Although this is very basic, I think it has fairly good potential. If
you want to see it work open "Structure 1.iam" then "double click" on
"Test Frame:1" near the top of the tree, then on the Parameters ("fx"
button) in the Panel Bar. Change the equation value next to the
following Parameter Names, when you return to the Assy you should see
everything update

Struct_Length 6000 (to 5000 or whatever)
Struct_Width 4000 (to 3000 or whatever)
Struct_Height 2000 (to...you get the idea)

I have also included a couple of .ide files (iFeatures) "AS Universal
Beam.ide" and "AS Universal Column.ide" You don't need these to run
the Assy, these ifeatures are the sketches for the beam and Column
extrusions. They are not finished yet, but I will propatate all UB's
and UC's.

Now the Good part, say you want to change the sections of the UB's or
UC's go into "Column 1.iam" then "Column 1:1" RMB "iFeature1:2" and
"edit ifeature" brings up a dialogue box, Click "200 UC 60" under
"Value" and change it to "150 UC 23" then finish. The column changes,
but the file name remains the same.

Still some work to do...

[Inv_kaos]

Not a bad method but I still think it is easier to do with a skeleton and FG. FG members (well all CC structural members) all use the same parameters, eg G_H, G_L, G_W, G_T, etc, no matter what the size or section. Use these parameters in your reference part/sketch for the offsets, add user parameters for your plate thicknesses etc. Use this reference part for all your assemblies. You can still use all the end treatments inside your child assemblies, and you don't need them between the individual assemblies because they bolt together. Change your reference part and the parent and all child assemblies update, easy as.

[sumayo]

Thanks IK, could you Zip and attach an example?

[Inv_kaos]

I had to knock up a small one that I was able to post. I haven't had time to link everything I would have liked but it shows the idea I was trying explain. This idea can be expanded to run every parameter.

I am just suggesting an option, I am not definitively saying this method would be the best.

I understand for your option you would have to essentially create another CC from scratch for all your iFeatures, right? If you do, would you be able to post these for me to have a play around with, since you are using AS structural members?

I have to head off, will be back on later, let me know how you go.

Cheers
Stew

[sumayo]

Thanks IK, What happens when you change the section size of the column? It seems lose the parameter "G_W" in "Reference Sketch:1" I think because when you change the section size it actually changes the part out. Is there a way around this?

[markg66]

Hi Sumayo,
I don't want to be seen as advertising another product but X-Steel or StruCad were designed for structural steelwork, and could be what you are looking for. The down side to this is they probably cost between £13,000 to £20,000.

Thanks

Mark (Inv 2008)

[sumayo]

Thanks Mark, also prosteel. Yes I am aware of packages that will do this, but the co I work for have invested in Inventor.

I think, with a bit of progamming you could probably get inventor to do it satisfactorily. I have converted all "AS" section profiles sketches to table driven iFeatures. Now I will set template parts and assy's (maybe iAssemblies) for Beams, Columns Plates and Bracing.

I am sitting here (on full pay) waiting for a project to start up (should be in about a month) so I have plenty of time (thought I would never say that) to do this.