At www.makeblock.cc its possible to buy aluminium robot parts and as I did (or better said, like the university did, because they paid for) complete assembly kits. This one is the starter kit blue and costs about 70€ at the local distributor. So I made some photos for documentation and fun:
Sadly the screws make scratches to the blue surface. So in case you plan multiple designs, there is no way to avoid them but to use some washers.