With the Product Design and Manufacturing Collections replacing the Product Design Suite a new FEA/Simulation module was included in the bundle of software. Nastran IN CAD or as Inventor Nastran as it has now been re-branded in 2021.
Inventor Professional has always had FEA but this is constrained to doing Linear Static and Modular studies. Inventor also has a frame/beam analysis based on the Robot technology which Autodesk acquired some years back and the full product is included in the AEC Collections which Autodesk offers for the Build environment.
If you need to do more complex studies, then Inventor Nastran (Nastran In CAD) is available if you purchased the Collections or have been upgraded to the Collections from your Product Design Suite.
Inventor Nastran has many more capabilities than Inventor Professional and similar to Inventor it runs from within Inventor. Yes, that is right you never leave your CAD environment which is a big plus. Whenever you have to leave the CAD environment it becomes a challenge when changes are made or with the interface itself. The most difficulty you will find when working with software is the interface and having to navigate around.
Inventor Nastran has the option to do non-linear analysis which is what most complex simulations will run.
As Inventor Professional FEA is very easy to get the hang of and there are not too many variables to input, I would suggest when getting a quick peak at what the object will do under certain loads, run a normal Inventor Professional simulation, but when the design starts to get complex, switch over to Nastran to get a more accurate overview.
