Design the robots out of materials that can be found in space. Then make them capable of reproduction. Then you can just scrap damaged robots as long as you can replace them fast enough. This also has the benefit that you just need to send up a tiny bootstrap population, but with time you will have quite the formidable workforce.
Doubtful there are enough resources to sustainably maintain much of anything in NEO. Asteroids with significant reservoirs are far apart and navigating between them is fraught.
Also how are the robots going to know what and how to maintain things? Otherwise they must be remote controlled. Yet their sensors break down over time.
Do reproducing robots even exist on Earth? How robust, nimble, and capable are they? Are their inputs found in space?
All that said, I do love the idea of a robot space colony producing useful things, even if all we gain are space probes and knowledge.
Robot production on earth is entangled with the whole global supply chain. I do believe many of the steps are automatic or semi-automatic.
It's """simply""" a matter of separating taking all those steps and separating them from the whole, packaging them into a bunch of boxes and sending them to space.
So in other words it's incredibly complicated... but possible.
Kind of a hand-wavy solution here - don't worry about maintenance just invent a self replicating universal tool that is either perfectly recyclable or cheap enough that we don't need to worry about their resource costs or cleanup. With that kind of tech nailed down pretty much ANY endeavor sounds very achievable (until the cheap startup version cuts one too many corners and the gray goo scenario begins I guess).
But isn't it just the natural progression of innovations like interchangeable parts and assembly line manufacturing?
And isn't it already a thing that we're progressing to with increased industrial output and reduced labour requirements?
This is where we're going, we just need an driver to push us to do it. Space exploration and resource extraction from the asteroid belt/moon to prevent the complete destruction of our environment seems to be as good a driver as any.
Design the robots out of materials that can be found in space. Then make them capable of reproduction. Then you can just scrap damaged robots as long as you can replace them fast enough. This also has the benefit that you just need to send up a tiny bootstrap population, but with time you will have quite the formidable workforce.