I assume you mean Gundam type robots?
Starship Operators
Cowboy Bebop
Kiddy Grade
Last Exile (although its more Steampunk than Sci-fi, but still pretty good)
Solty Rei (drama with sci-fi elements)
Birdy the Mighty 1 & 2 (sort of)
Stellvia of the Universe
Planetes
Crest of the Stars and Banner of the Stars






