Automatic origin constraint

Hi,

I have been working with multiple cad applications and one of the most useful techniques I've ever learned was multi-body modeling. This technique allows users to export solid bodies as separate part files (derrived of  course) as well as an assembly (no constraints though, at least not within inventor and/or solidworks).

What I would like to know is, do you know of or do you have a macro for adding origin to origin constraints for parts sharing the same origin or even better to use designated work planes to constrain parts to the assembly origin automatically.

Specifically, my objective is to eliminate any relationships that may exist from part to part, this way any updates I add to the master model(s) would simply cause the entire assembly to update accordingly without the need to reconstrain.

I have been able to pull this off quite easily within inventor, but in solidworks its not so straightforward.

For instance,

Inside inventor, I create a part file with sketches and workplanes that pretty much contain general design intent info (at least enough information to drive assembly, part locations, clearances, thicknesses, tolerances, as well as major features and even some critical component locations). Pretty much any information that would be critical to the design intent is included into a master file. However this file will generally have no features or parts or any solid modeling data whatsoever. Then I derrive this file into new part files where I use the pre-defined data to model new parts. Yes sometimes when i model a parts this way, some parts have to reference eachother. Once in the assembly however, I can go ahead and constrain the origins and whenever I make changes nothing gets messed up.

Please review and advise.

Thanks.