Autodesk Forma Model Coordination Not Highlighting Clashes

[pamela_fisher]

I have multiple views coming from a single 36.5 MB RVT file into a Model Coordination space in Autodesk Forma.

I can plainly see multiple clashes but when running clash detection approximately one in fifty clashes is actually being highlighted by clash detection.

I have run clash detection between the whole models (views). I have also tried multiple different selection sets that are picking up the clashing items. No matter how I set up the clash detection, it is not highlighting clashes.

This is a relatively new project so I do not have any issues flagged as "Not an Issue". 

Also, when looking at this same coordination space in Navisworks, I can see the additional clashes not being picked up in Forma.

It's been doing this off and on since last week. I know the week of AU things always get glitchy but this making Forma unworkable.

I had another project with the same exact setup that I had issues with last week but was eventually able to highlight and tag issues.

[josebaqueror]

The tell here is that you have multiple VIEWS coming from a single RVT into the coordination space. Model Coordination is built to clash SEPARATE models against each other, not views of the same source file, and that is almost certainly why it is dropping most of what Navisworks shows you.

When the geometry all lives in one file, the engine largely treats it as one model and does not clash it against itself, so the clashes you can plainly see (which sit inside that single file) mostly never get surfaced. Navisworks does not care about that, it will clash everything against everything, which is exactly why it catches the ones ACC skips. Selection sets do not get around it, because the limitation is at the model level, not the selection level.

Two ways forward depending on your setup:

1. If those views actually represent different disciplines or trades, publish them as SEPARATE models (separate files, or separate consumed/Design Collaboration models) into the coordination space, so the engine has distinct models to clash against each other. That is the setup Model Coordination expects, and it will start behaving like Navisworks.

2. If the clashing genuinely happens inside one integrated model and cannot be split, then intra-model interference is not really Model Coordination's job. Revit's own Interference Check, or Navisworks which you already see works, is the right tool for that case.

So the question that decides it: are these views separate discipline models that happen to be exported from one RVT, or is it one integrated model you are trying to self-clash? If it is the former, splitting them into separate coordinated models should light up the clashes you are missing.

How is the source RVT organized, one discipline or several combined in the single file?