Modelling Tolerances

[Anonymous]

I am having some trouble with geometric tolerances in my Robot model.

The model was imported from Revit and has walls and panels that don't quite meet. I have checked the dimensional accuracy to 3dp and have manually changed the coordinates of walls that don't match up to retify the model. I have just redrawn the panels once the walls were sorted.

After going through this process, I have started meshing the structure to find that multiple nodes are being placed in apparant intersections between walls and panels (I have checked one particular instance to 9dp).

My problem is then, to what dimensional accuracy do I need to model the structure in order to avoid these discrepancies?

This includes accuracy between levels as I know cladding panels are an issue when they are not completely vertical or drawn to panel edges.

[Rafal.Gaweda]

1. Do not use regular mesh
2. Send us robot file

[Anonymous]

https://www.dropbox.com/s/y5fcx8tiol41604/8518%2013%2009%2024%20Robot%20Model%20Rev%20-%20.rtd

[Rafal.Gaweda]

Hope you are aware of "hanging walls".

Checking model - we will see.

Why do not you make correct model  or correct analytical model in revit not to have these type of "parapets"

Column 78 too long:

Too short walls on 1st floor

Panels and openings  128 415 420 425 428 434 463  do not meet on common edge.

Panel 44 - stange geometry near opening

Panel and opening 302 309

Panel 1117 overlapping other panels - must be shorter

[Anonymous]

The model is not yet complete, hence why there are still mistakes and 'features'.

Would the 'correct analytical model' command in Revit cure most of the inconsistancies I am coming across?

Would your appraoch to the misaligned walls and panels be to manually enter coordinates?

I'm guessing the programs tolerances are less than 0.001m (i.e. 3dp), so what accuracy do I have to go to when checking coordinates or do I have to manually enter ALL coordinates to ensure that the walls and panels match up perfectly?

[Rafal.Gaweda · Accepted solution]

 

Would the 'correct analytical model' command in Revit cure most of the inconsistancies I am coming across?

I do not know yet, checking model. 

Would your appraoch to the misaligned walls and panels be to manually enter coordinates?

PLease provide example panel numbers.

I'm guessing the programs tolerances are less than 0.001m (i.e. 3dp), so what accuracy do I have to go to when checking coordinates or do I have to manually enter ALL coordinates to ensure that the walls and panels match up perfectly?

Depending on mesh settings (regular ?) - sometimes 9dp.

This can help you:

http://forums.autodesk.com/t5/Robot-Structural-Analysis/Rounding-up-coordinates-API/td-p/3430533/pag...

http://forums.autodesk.com/t5/Robot-Structural-Analysis/VBA-Excel-macro-for-any-object-geometry-modi...

http://forums.autodesk.com/t5/Robot-Structural-Analysis/Panel-contour-points-modification-API/td-p/3...

[Rafal.Gaweda]

All the errors I found described \ shown above.

None of them is related to program errors or accuracy. Just as far as I can see your or revit inaccuracy.

Corrected and meshed model here : http://we.tl/TmdMAOU8YS

[Anonymous]

I had the same issue while importing the model from Revit.

I was expecting to have a proper way to handel such tolerance issue caused by Revit,

it is 0.001m ( 1 mm ) .

There is no proper way to find out these places with the small gapes or overlaps.

Might me the solution is to have the option of changing the tolerance in CFD.

Regards,

Yuval

[Rafal.Gaweda]

From curiosity : are you taking about Revit, Robot or CFD ?

[Anonymous]

The problem starts from Revit,
I do not mind to have a way to fix it while importing into CFD,
As of now I am launcing the CFD from Revit.

For some reason there are tolerance issue in Revit but for the users who
are staying with Revit and do not trying to use the the model in CFD, they
are not aware of the issue
For normal Revit use ( after using the attach to connect wall to the floor
and the cilling ) all is connected perfect. BUT in many cases for CFD this
is not OK. There is a small gape that cause many many unneccesery hours of
lookin for the problematic place.

For the CFD users this is BIG BIG issue
We need to have a proper tool to ignore this small distance ( 0.001 m ).


Regards,

Yuval

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[Rafal.Gaweda]

I am afraid you accessed wrong forum.
It is Robot forum, not CFD.

[Anonymous]

Might be wrong forum but the same issue

Revit ==> CFD
The root cause of the issues are the way Revit DB keeps the data

Regards,

Yuval

--
*בברכה*


*יובל הירש*
*______________________*
*איל ניב מהנדסים ויועצים בע"מ*
*דרך השלום 7 תל אביב*
*נייד: 054-2111751*
*טלפון: 03-6044564*
*פקס: 03-6044589*

[Rafal.Gaweda]

Some programs can deal with it very easily: