I have search for this answer all over, but didn't seem to find an exact answer. It there a way to put Inventor drawings into AutoCAD and maintain associability. What I mean by that is once I have exported or imported a drawing into AutoCAD, then I change some part of the drawing in Inventor, will it update the AutoCAD drawing automatically?
Yes, but you have to follow this process.
In AutoCAD launch Design Center
Browse to the Inventor DWG (can't be an IDW)
Insert the Views from the Inventor DWG
Now, if the Inventor DWG changes you have to use Design Center not to reinsert the block, but simply right click on the view you want to update and select Redefine Only.
Essentially you have to know what Inventor DWGs updated and what Views need refreshed in AutoCAD. This is just fantastic for Floor Plans of equipment, but with the new Factory Design Suite, the process is even better for associativity between a library of stations and Inventor (in Factory Design you can place 2D footprints of the blocks in ACAD and then when it is taken to Inventor it will automatically populate the 3D assets based on the 2D layout of the factory floor and will update from the ACAD side).
Why not just keep it as an Inventor DWG? You can open in AutoCAD still, but the views are not editable.
There is the third choose.
In AutCAD 2012, it introduces the new features to create views for the 3D modeling. The base view and projection view are already supported. The commands can be invoked by "VIEWBASE" and "VIEWPROJ". Also they can be found in Annotate tab | Drawing Views panel.
The views created in AutoCAD is associated to the Inventor modeling. When Inventor modeling changes, AutoCAD can detect the change, and update the view correspondingly.