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PTAadrian
Posts: 23
Registered: ‎10-22-2012
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Modelling Tolerances

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10-31-2013 03:07 AM

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.

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Rafal.Gaweda
Posts: 4,987
Registered: ‎04-26-2010

Re: Modelling Tolerances

10-31-2013 03:13 AM in reply to: PTAadrian
1. Do not use regular mesh
2. Send us robot file


Rafal Gaweda
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Contributor
PTAadrian
Posts: 23
Registered: ‎10-22-2012
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Rafal.Gaweda
Posts: 4,987
Registered: ‎04-26-2010

Re: Modelling Tolerances

10-31-2013 03:37 AM in reply to: PTAadrian

Hope you are aware of "hanging walls".

Checking model - we will see.

 

hw.jpg

 

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

 

 

parapets.jpg

 

Column 78 too long:

 

column78.jpg

 

Too short walls on 1st floor

 

walls1fl.jpg

 

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

 

Panel 44 - stange geometry near opening

 

panjel 44.jpg

 

 

Panel and opening 302 309

 

302_309.jpg

 

Panel 1117 overlapping other panels - must be shorter

 

panel1117.jpg



Rafal Gaweda
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Contributor
PTAadrian
Posts: 23
Registered: ‎10-22-2012

Re: Modelling Tolerances

10-31-2013 03:50 AM in reply to: Rafal.Gaweda

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?

 

 

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Rafal.Gaweda
Posts: 4,987
Registered: ‎04-26-2010

Re: Modelling Tolerances

10-31-2013 04:12 AM in reply to: PTAadrian
 

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
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Product Support
Rafal.Gaweda
Posts: 4,987
Registered: ‎04-26-2010

Re: Modelling Tolerances

10-31-2013 07:03 AM in reply to: 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



Rafal Gaweda
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Member
eyaln
Posts: 5
Registered: ‎07-13-2011

Re: Modelling Tolerances

07-22-2014 02:19 AM in reply to: Rafal.Gaweda

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

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Product Support
Rafal.Gaweda
Posts: 4,987
Registered: ‎04-26-2010

Re: Modelling Tolerances

07-22-2014 02:26 AM in reply to: eyaln
From curiosity : are you taking about Revit, Robot or CFD ?


Rafal Gaweda
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Member
eyaln
Posts: 5
Registered: ‎07-13-2011

Re: Modelling Tolerances

07-22-2014 02:39 AM in reply to: Rafal.Gaweda
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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