I don't think hes an android, I get the impression its some kind of environmental suit.
I figured that it was just because there IS an actor in a suit. But I got that impression as well .
According to Wikipedia, MrSouthpaw is correct. They describe Isaac as "A member of the artificial, non-biological race from Kaylon-1 that views biological lifeforms, including humans, as inferior."Artificial life form, iirc.