At the current time, October 2020, there is no way to directly import your model into Unity 3D,

We have two main programs that we can use as a middleman, Navisworks or 3Ds Max.

In this blog I will demonstrate this, using Navisworks.

This is faster and more robust than the 3Ds Max route,

though has far fewer editing options.

To do this,

First make AutoCAD Plant 3D in installed and Then Navisworks or else the object enablers will not work correctly,

For Navisworks, make sure you have Navisworks Manage and that it matches the same version as your AutoCAD Plant 3D.

Open the Plant model you want to export,

Then type the command NWCOUT

If this option is not available, check or maybe reinstall Navisworks.

Browse to the directory you wish to save the file to,

Give it a name and then select Save.

Now we going to Navisworks, do not close Plant 3D OR the Plant Model,

If you close these, the Object enablers will not function, and your model will be missing parts.

In Navisworks,

Select the Application Menu,

Then select Open.

Browse to the file location

If you cant see the file, make sure the Files of Type is set to the .nwc format.

Select the file and then click Open.

The Model should now be loaded,

Next, we select the Application menu button, Export and FBX.

Normally these default options are OK, so select the OK button.

Save the fbx file.

Go to Unity,

Open the Assets dropdown off the file menu.

Select Import New Asset…

Browse to the location you saved the model,

Select it and then click Import.

Once imported,

select the model and on the right panel, Check the Generate Colliders box.

Now just drag the model into the scene Hierarchy.

Congratulations!

Your scene should now be in Unity!