the only difficulty i see is in creating structural members from folded aluminum sheets .
you can do it, but you would need to be a sheet metal man and be skilled with a bending brake.
better to spring for a few pieces of aluminum extrusion or angle iron.
as well, rather than aluminum sheet, the teardrop shaped end pieces could be made of wood or plastic. something you can get a screw into rather than all those folded over tabs.