Meshing issues

[ronny_raygun371629]

Hi, I'm a new Robot user, and have been given a rather complex Revit model to analyse in Robot. The export from Revit to Robot was not without issue, although the warnings in Robot have now mostly been resolved.

I have now attempted to mesh the model, which was a long way from being successful. I attempted to mesh the entire model in one go, is this the best option?
In some areas the model did not mesh at all, in others nodes were created but no mesh linked them up.
To attempt to resolve this I deleted the isolated nodes, and ran local mesh generation on the unmeshed panels, is this the right thing to do? Once this was done unsurprisingly there were many areas of incoherent meshing at junctions of core walls and slabs. Can anyone advise on the best way to resolve this issue? I attempted to move some of the nodes manually to link them up but this just caused further issues.

Advice on the above would be very welcome.

Thanks

[jpo82]

Hi

If you have model with many panels in it, meshing whole structure in one go rarely works. Usually best way but unfortunately quite slow way is to mehs first all wall panels floor by floor and then all slabs. This gives usually good mesh.

One thing is that in Robot two points are connected to eah other or they aren't. There's no such thing as "close enough." So if somebody else has modelled your structure in Revit, there might be some minor mistakes in Revit model that gives you a lot of headache in Robot. That's why if I have to do a Robot model using panels I avoid importing anything as reference or directly in Robot since references or imports may contain minor geometry mistakes that will cause you a lot's of headache in form of incoherent mesh. I've found that for me it seems to be easiest and fastest way to model whole structure in Robot or use use very simple dwg references where all geometry is 100 % right and simplified enough for analysis.

Hope this helps a little.

[pawel.pulak]

The effects you observe suggest that inaccuracies still exist in your model.
As written by jpo82 the sequenatial meshing of first walls and then slabs may help a little.

Additionally you can change meshing parameters from controlled by the number of division to controlled by the base size of the mesh and you can switch off regular mesh. It is discribed also in message 4 of this forum post: http://forums.autodesk.com/t5/Autode...ght/true#M2401
Some improvement can be often obtained increasing the tolerance of model generation - specifying user-defined value on Structure Model tab of Analysis Type window.
If model is somehow regular then defining grid lines and using Edit/Detailed Correct to snap to them may correct the model and help to avoid meshing problems.
Useful API tools for inspection and correction of Robot models can be found in other posts of above mentioned forum.

Regards,