How to calculate intermediate polygon between two polygons using ArcGIS

SlobodanKomatina1

I have a two polygons, the big one and the small one inside of the big one. Now I want to create the new polygon which is on the average middle between these two (big and small). I have used Erase tool to create just one donate polygon (without the small one in the middle) and to create negative buffer, but that is not a good idea. New polygon should have some mix of geometries between small and big one.

NOTE that these two polygons doesn't have the same geometry.

All of these I want to finish using ArcGIS. 

ChrisDonohue__GISP

Just a quick workflow idea that could be tried if you have access to Spatial Analyst or 3D Analyst.  Untested, but I think this could work.  It would need to be fleshed out with the specific processes (this is just the basic process).

1. Convert the polygons to lines
2. Combine into one feature class (if not already)
3. Add an integer field called "Elevation"
4. Populate one line with zero and the other with 100
5. Convert the lines to a surface (raster)
6. Contour the surface, specifying an elevation of 50.  This will essentially produce the result you are seeking.
7. Convert to vector, then Convert the lines back to polygons.

Chris Donohue, GISP