If you're looking for an indepth discussion as to how the Gundam colonies work, then that line of inquiry can go into the
General Gundam Technology thread. If you just want a quick overview, just about all of the Gundam space colonies are based on the O'Neill stations laid out in the seminal
The High Frontier. The UC colonies are Island Three designs, the Wing colonies are Island One designs, and the very concept of large scale habitation at the lagrange points was in Gerard O'Neill's book.